Drop unused onlab-nio module

Change-Id: I52141335643ad5b62b2a9cebe4d79faf0762e3e0

-<?xml version="1.0" encoding="UTF-8"?>
-<!--
-  ~ Copyright 2014 Open Networking Laboratory
-  ~
-  ~ Licensed under the Apache License, Version 2.0 (the "License");
-  ~ you may not use this file except in compliance with the License.
-  ~ You may obtain a copy of the License at
-  ~
-  ~     http://www.apache.org/licenses/LICENSE-2.0
-  ~
-  ~ Unless required by applicable law or agreed to in writing, software
-  ~ distributed under the License is distributed on an "AS IS" BASIS,
-  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  ~ See the License for the specific language governing permissions and
-  ~ limitations under the License.
-  -->
-<project xmlns="http://maven.apache.org/POM/4.0.0"
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
-    <modelVersion>4.0.0</modelVersion>
-
-    <parent>
-        <groupId>org.onosproject</groupId>
-        <artifactId>onlab-utils</artifactId>
-        <version>1.5.0-SNAPSHOT</version>
-        <relativePath>../pom.xml</relativePath>
-    </parent>
-
-    <artifactId>onlab-nio</artifactId>
-    <packaging>bundle</packaging>
-
-    <description>Fast network I/O using Java NIO</description>
-
-    <dependencies>
-        <dependency>
-            <groupId>com.google.guava</groupId>
-            <artifactId>guava-testlib</artifactId>
-            <scope>test</scope>
-        </dependency>
-                <dependency>
-            <groupId>commons-pool</groupId>
-            <artifactId>commons-pool</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.onosproject</groupId>
-            <artifactId>onos-api</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.onosproject</groupId>
-            <artifactId>onlab-misc</artifactId>
-        </dependency>
-        <dependency>
-            <groupId>org.onosproject</groupId>
-            <artifactId>onlab-junit</artifactId>
-            <scope>test</scope>
-        </dependency>
-    </dependencies>
-</project>

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-/**
- * Base {@link Message} implementation.
- */
-public abstract class AbstractMessage implements Message {
-
-    protected int length;
-
-    @Override
-    public int length() {
-        return length;
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import java.io.IOException;
-import java.net.SocketAddress;
-import java.net.StandardSocketOptions;
-import java.nio.channels.SelectionKey;
-import java.nio.channels.ServerSocketChannel;
-import java.util.Iterator;
-
-import static com.google.common.base.Preconditions.checkNotNull;
-
-/**
- * Selector loop derivative tailored to acceptConnection inbound connections.
- */
-public abstract class AcceptorLoop extends SelectorLoop {
-
-    private SocketAddress listenAddress;
-    private ServerSocketChannel socketChannel;
-
-    /**
-     * Creates an acceptor loop with the specified selection timeout and
-     * accepting connections on the the given address.
-     *
-     * @param selectTimeout selection timeout; specified in millis
-     * @param listenAddress socket address where to listen for connections
-     * @throws IOException if the backing selector cannot be opened
-     */
-    public AcceptorLoop(long selectTimeout, SocketAddress listenAddress)
-            throws IOException {
-        super(selectTimeout);
-        this.listenAddress = checkNotNull(listenAddress, "Address cannot be null");
-    }
-
-    /**
-     * Hook to accept an inbound connection on the specified socket channel.
-     *
-     * @param channel socketChannel where an accept operation awaits
-     * @throws IOException if the accept operation cannot be processed
-     */
-    protected abstract void acceptConnection(ServerSocketChannel channel) throws IOException;
-
-    /**
-     * Opens a new server socket channel configured in non-blocking mode and
-     * bound to the loop's listen address.
-     *
-     * @throws IOException if unable to open or configure the socket channel
-     */
-    protected synchronized void openChannel() throws IOException {
-        socketChannel = ServerSocketChannel.open();
-        socketChannel.configureBlocking(false);
-        socketChannel.setOption(StandardSocketOptions.SO_REUSEADDR, true);
-        socketChannel.register(selector, SelectionKey.OP_ACCEPT);
-        socketChannel.bind(listenAddress);
-    }
-
-    /**
-     * Closes the server socket channel.
-     *
-     * @throws IOException if unable to close the socketChannel
-     */
-    protected synchronized void closechannel() throws IOException {
-        if (socketChannel != null) {
-            socketChannel.close();
-            socketChannel = null;
-        }
-    }
-
-    @Override
-    public void shutdown() {
-        try {
-            closechannel();
-        } catch (IOException e) {
-            log.warn("Unable to close the socketChannel", e);
-        }
-        super.shutdown();
-    }
-
-    @Override
-    protected void loop() throws IOException {
-        openChannel();
-        notifyReady();
-
-        // Keep looping until told otherwise.
-        while (isRunning()) {
-            // Attempt a selection; if no operations selected or if signalled
-            // to shutdown, spin through.
-            int count = selector.select(selectTimeout);
-            if (count == 0 || !isRunning()) {
-                continue;
-            }
-
-            // Iterate over all keys selected for an operation and process them.
-            Iterator<SelectionKey> keys = selector.selectedKeys().iterator();
-            while (keys.hasNext()) {
-                // Fetch the key and remove it from the pending list.
-                SelectionKey key = keys.next();
-                keys.remove();
-
-                // If the key has a pending acceptConnection operation, process it.
-                if (key.isAcceptable()) {
-                    acceptConnection((ServerSocketChannel) key.channel());
-                }
-            }
-        }
-    }
-
-}
-

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import java.io.IOException;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.CancelledKeyException;
-import java.nio.channels.ClosedChannelException;
-import java.nio.channels.SelectableChannel;
-import java.nio.channels.SelectionKey;
-import java.nio.channels.SocketChannel;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Queue;
-import java.util.Set;
-import java.util.concurrent.ConcurrentLinkedQueue;
-import java.util.concurrent.CopyOnWriteArraySet;
-
-/**
- * I/O loop for driving inbound & outbound {@link Message} transfer via
- * {@link MessageStream}.
- *
- * @param <M> message type
- * @param <S> message stream type
- */
-public abstract class IOLoop<M extends Message, S extends MessageStream<M>>
-        extends SelectorLoop {
-
-    // Queue of requests for new message streams to enter the IO loop processing.
-    private final Queue<NewStreamRequest> newStreamRequests = new ConcurrentLinkedQueue<>();
-
-    // Carries information required for admitting a new message stream.
-    private class NewStreamRequest {
-        private final S stream;
-        private final SelectableChannel channel;
-        private final int op;
-
-        public NewStreamRequest(S stream, SelectableChannel channel, int op) {
-            this.stream = stream;
-            this.channel = channel;
-            this.op = op;
-        }
-    }
-
-    // Set of message streams currently admitted into the IO loop.
-    private final Set<MessageStream<M>> streams = new CopyOnWriteArraySet<>();
-
-    /**
-     * Creates an IO loop with the given selection timeout.
-     *
-     * @param timeout selection timeout in milliseconds
-     * @throws IOException if the backing selector cannot be opened
-     */
-    public IOLoop(long timeout) throws IOException {
-        super(timeout);
-    }
-
-    /**
-     * Returns the number of message stream in custody of the loop.
-     *
-     * @return number of message streams
-     */
-    public int streamCount() {
-        return streams.size();
-    }
-
-    /**
-     * Creates a new message stream backed by the specified socket channel.
-     *
-     * @param byteChannel backing byte channel
-     * @return newly created message stream
-     */
-    protected abstract S createStream(ByteChannel byteChannel);
-
-    /**
-     * Removes the specified message stream from the IO loop.
-     *
-     * @param stream message stream to remove
-     */
-    protected void removeStream(MessageStream<M> stream) {
-        streams.remove(stream);
-    }
-
-    /**
-     * Processes the list of messages extracted from the specified message
-     * stream.
-     *
-     * @param messages non-empty list of received messages
-     * @param stream   message stream from which the messages were extracted
-     */
-    protected abstract void processMessages(List<M> messages, MessageStream<M> stream);
-
-    /**
-     * Completes connection request pending on the given selection key.
-     *
-     * @param key selection key holding the pending connect operation.
-     * @throws IOException when I/O exception of some sort has occurred
-     */
-    protected void connect(SelectionKey key) throws IOException {
-        SocketChannel ch = (SocketChannel) key.channel();
-        ch.finishConnect();
-        if (key.isValid()) {
-            key.interestOps(SelectionKey.OP_READ);
-        }
-    }
-
-    /**
-     * Processes an IO operation pending on the specified key.
-     *
-     * @param key selection key holding the pending I/O operation.
-     */
-    protected void processKeyOperation(SelectionKey key) {
-        @SuppressWarnings("unchecked")
-        S stream = (S) key.attachment();
-
-        try {
-            // If the key is not valid, bail out.
-            if (!key.isValid()) {
-                stream.close();
-                return;
-            }
-
-            // If there is a pending connect operation, complete it.
-            if (key.isConnectable()) {
-                try {
-                    connect(key);
-                } catch (IOException | IllegalStateException e) {
-                    log.warn("Unable to complete connection", e);
-                }
-            }
-
-            // If there is a read operation, slurp as much data as possible.
-            if (key.isReadable()) {
-                List<M> messages = stream.read();
-
-                // No messages or failed flush imply disconnect; bail.
-                if (messages == null || stream.hadError()) {
-                    stream.close();
-                    return;
-                }
-
-                // If there were any messages read, process them.
-                if (!messages.isEmpty()) {
-                    try {
-                        processMessages(messages, stream);
-                    } catch (RuntimeException e) {
-                        onError(stream, e);
-                    }
-                }
-            }
-
-            // If there are pending writes, flush them
-            if (key.isWritable()) {
-                stream.flushIfPossible();
-            }
-
-            // If there were any issued flushing, close the stream.
-            if (stream.hadError()) {
-                stream.close();
-            }
-
-        } catch (CancelledKeyException e) {
-            // Key was cancelled, so silently close the stream
-            stream.close();
-        } catch (IOException e) {
-            if (!stream.isClosed() && !isResetByPeer(e)) {
-                log.warn("Unable to process IO", e);
-            }
-            stream.close();
-        }
-    }
-
-    // Indicates whether or not this exception is caused by 'reset by peer'.
-    private boolean isResetByPeer(IOException e) {
-        Throwable cause = e.getCause();
-        return cause != null && cause instanceof IOException &&
-                cause.getMessage().contains("reset by peer");
-    }
-
-    /**
-     * Hook to allow intercept of any errors caused during message processing.
-     * Default behaviour is to rethrow the error.
-     *
-     * @param stream message stream involved in the error
-     * @param error  the runtime exception
-     */
-    protected void onError(S stream, RuntimeException error) {
-        throw error;
-    }
-
-    /**
-     * Admits a new message stream backed by the specified socket channel
-     * with a pending accept operation.
-     *
-     * @param channel backing socket channel
-     * @return newly accepted message stream
-     */
-    public S acceptStream(SocketChannel channel) {
-        return createAndAdmit(channel, SelectionKey.OP_READ);
-    }
-
-
-    /**
-     * Admits a new message stream backed by the specified socket channel
-     * with a pending connect operation.
-     *
-     * @param channel backing socket channel
-     * @return newly connected message stream
-     */
-    public S connectStream(SocketChannel channel) {
-        return createAndAdmit(channel, SelectionKey.OP_CONNECT);
-    }
-
-    /**
-     * Creates a new message stream backed by the specified socket channel
-     * and admits it into the IO loop.
-     *
-     * @param channel socket channel
-     * @param op      pending operations mask to be applied to the selection
-     *                key as a set of initial interestedOps
-     * @return newly created message stream
-     */
-    private synchronized S createAndAdmit(SocketChannel channel, int op) {
-        S stream = createStream(channel);
-        streams.add(stream);
-        newStreamRequests.add(new NewStreamRequest(stream, channel, op));
-        selector.wakeup();
-        return stream;
-    }
-
-    /**
-     * Safely admits new streams into the IO loop.
-     */
-    private void admitNewStreams() {
-        Iterator<NewStreamRequest> it = newStreamRequests.iterator();
-        while (isRunning() && it.hasNext()) {
-            try {
-                NewStreamRequest request = it.next();
-                it.remove();
-                SelectionKey key = request.channel.register(selector, request.op,
-                                                            request.stream);
-                request.stream.setKey(key);
-            } catch (ClosedChannelException e) {
-                log.warn("Unable to admit new message stream", e);
-            }
-        }
-    }
-
-    @Override
-    protected void loop() throws IOException {
-        notifyReady();
-
-        // Keep going until told otherwise.
-        while (isRunning()) {
-            admitNewStreams();
-
-            // Process flushes & write selects on all streams
-            for (MessageStream<M> stream : streams) {
-                stream.flushIfWriteNotPending();
-            }
-
-            // Select keys and process them.
-            int count = selector.select(selectTimeout);
-            if (count > 0 && isRunning()) {
-                Iterator<SelectionKey> it = selector.selectedKeys().iterator();
-                while (it.hasNext()) {
-                    SelectionKey key = it.next();
-                    it.remove();
-                    processKeyOperation(key);
-                }
-            }
-        }
-    }
-
-    /**
-     * Prunes the registered streams by discarding any stale ones.
-     *
-     * @return number of remaining streams
-     */
-    public synchronized int pruneStaleStreams() {
-        for (MessageStream<M> stream : streams) {
-            if (stream.isStale()) {
-                stream.close();
-            }
-        }
-        return streams.size();
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-/**
- * Representation of a message transferred via {@link MessageStream}.
- */
-public interface Message {
-
-    /**
-     * Gets the message length in bytes.
-     *
-     * @return number of bytes
-     */
-    int length();
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.onlab.util.Counter;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.IOException;
-import java.nio.ByteBuffer;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.SelectionKey;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.Objects;
-
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
-import static java.lang.System.currentTimeMillis;
-import static java.nio.ByteBuffer.allocateDirect;
-
-/**
- * Bi-directional message stream for transferring messages to & from the
- * network via two byte buffers.
- *
- * @param <M> message type
- */
-public abstract class MessageStream<M extends Message> {
-
-    protected Logger log = LoggerFactory.getLogger(getClass());
-
-    private final IOLoop<M, ?> loop;
-    private final ByteChannel channel;
-    private final int maxIdleMillis;
-
-    private final ByteBuffer inbound;
-    private ByteBuffer outbound;
-    private SelectionKey key;
-
-    private volatile boolean closed = false;
-    private volatile boolean writePending;
-    private volatile boolean writeOccurred;
-
-    private Exception ioError;
-    private long lastActiveTime;
-
-    private final Counter bytesIn = new Counter();
-    private final Counter messagesIn = new Counter();
-    private final Counter bytesOut = new Counter();
-    private final Counter messagesOut = new Counter();
-
-    /**
-     * Creates a message stream associated with the specified IO loop and
-     * backed by the given byte channel.
-     *
-     * @param loop          IO loop
-     * @param byteChannel   backing byte channel
-     * @param bufferSize    size of the backing byte buffers
-     * @param maxIdleMillis maximum number of millis the stream can be idle
-     *                      before it will be closed
-     */
-    protected MessageStream(IOLoop<M, ?> loop, ByteChannel byteChannel,
-                            int bufferSize, int maxIdleMillis) {
-        this.loop = checkNotNull(loop, "Loop cannot be null");
-        this.channel = checkNotNull(byteChannel, "Byte channel cannot be null");
-
-        checkArgument(maxIdleMillis > 0, "Idle time must be positive");
-        this.maxIdleMillis = maxIdleMillis;
-
-        inbound = allocateDirect(bufferSize);
-        outbound = allocateDirect(bufferSize);
-    }
-
-    /**
-     * Gets a single message from the specified byte buffer; this is
-     * to be done without manipulating the buffer via flip, reset or clear.
-     *
-     * @param buffer byte buffer
-     * @return read message or null if there are not enough bytes to read
-     * a complete message
-     */
-    protected abstract M read(ByteBuffer buffer);
-
-    /**
-     * Puts the specified message into the specified byte buffer; this is
-     * to be done without manipulating the buffer via flip, reset or clear.
-     *
-     * @param message message to be write into the buffer
-     * @param buffer  byte buffer
-     */
-    protected abstract void write(M message, ByteBuffer buffer);
-
-    /**
-     * Closes the message buffer.
-     */
-    public void close() {
-        synchronized (this) {
-            if (closed) {
-                return;
-            }
-            closed = true;
-        }
-
-        bytesIn.freeze();
-        bytesOut.freeze();
-        messagesIn.freeze();
-        messagesOut.freeze();
-
-        loop.removeStream(this);
-        if (key != null) {
-            try {
-                key.cancel();
-                key.channel().close();
-            } catch (IOException e) {
-                log.warn("Unable to close stream", e);
-            }
-        }
-    }
-
-    /**
-     * Indicates whether this buffer has been closed.
-     *
-     * @return true if this stream has been closed
-     */
-    public synchronized boolean isClosed() {
-        return closed;
-    }
-
-    /**
-     * Returns the stream IO selection key.
-     *
-     * @return socket channel registration selection key
-     */
-    public SelectionKey key() {
-        return key;
-    }
-
-    /**
-     * Binds the selection key to be used for driving IO operations on the stream.
-     *
-     * @param key IO selection key
-     */
-    public void setKey(SelectionKey key) {
-        this.key = key;
-        this.lastActiveTime = currentTimeMillis();
-    }
-
-    /**
-     * Returns the IO loop to which this stream is bound.
-     *
-     * @return I/O loop used to drive this stream
-     */
-    public IOLoop<M, ?> loop() {
-        return loop;
-    }
-
-    /**
-     * Indicates whether the any prior IO encountered an error.
-     *
-     * @return true if a write failed
-     */
-    public boolean hadError() {
-        return ioError != null;
-    }
-
-    /**
-     * Gets the prior IO error, if one occurred.
-     *
-     * @return IO error; null if none occurred
-     */
-    public Exception getError() {
-        return ioError;
-    }
-
-    /**
-     * Reads, without blocking, a list of messages from the stream.
-     * The list will be empty if there were not messages pending.
-     *
-     * @return list of messages or null if backing channel has been closed
-     * @throws IOException if messages could not be read
-     */
-    public List<M> read() throws IOException {
-        try {
-            int read = channel.read(inbound);
-            if (read != -1) {
-                // Read the messages one-by-one and add them to the list.
-                List<M> messages = new ArrayList<>();
-                M message;
-                inbound.flip();
-                while ((message = read(inbound)) != null) {
-                    messages.add(message);
-                    messagesIn.add(1);
-                    bytesIn.add(message.length());
-                }
-                inbound.compact();
-
-                // Mark the stream with current time to indicate liveness.
-                lastActiveTime = currentTimeMillis();
-                return messages;
-            }
-            return null;
-
-        } catch (Exception e) {
-            throw new IOException("Unable to read messages", e);
-        }
-    }
-
-    /**
-     * Writes the specified list of messages to the stream.
-     *
-     * @param messages list of messages to write
-     * @throws IOException if error occurred while writing the data
-     */
-    public void write(List<M> messages) throws IOException {
-        synchronized (this) {
-            // First write all messages.
-            for (M m : messages) {
-                append(m);
-            }
-            flushUnlessAlreadyPlanningTo();
-        }
-    }
-
-    /**
-     * Writes the given message to the stream.
-     *
-     * @param message message to write
-     * @throws IOException if error occurred while writing the data
-     */
-    public void write(M message) throws IOException {
-        synchronized (this) {
-            append(message);
-            flushUnlessAlreadyPlanningTo();
-        }
-    }
-
-    // Appends the specified message into the internal buffer, growing the
-    // buffer if required.
-    private void append(M message) {
-        // If the buffer does not have sufficient length double it.
-        while (outbound.remaining() < message.length()) {
-            doubleSize();
-        }
-        write(message, outbound);
-        messagesOut.add(1);
-        bytesOut.add(message.length());
-    }
-
-    // Forces a flush, unless one is planned already.
-    private void flushUnlessAlreadyPlanningTo() throws IOException {
-        if (!writeOccurred && !writePending) {
-            flush();
-        }
-    }
-
-    /**
-     * Flushes any pending writes.
-     *
-     * @throws IOException if flush failed
-     */
-    public void flush() throws IOException {
-        synchronized (this) {
-            if (!writeOccurred && !writePending) {
-                outbound.flip();
-                try {
-                    channel.write(outbound);
-                } catch (IOException e) {
-                    if (!closed && !Objects.equals(e.getMessage(), "Broken pipe")) {
-                        log.warn("Unable to write data", e);
-                        ioError = e;
-                    }
-                }
-                lastActiveTime = currentTimeMillis();
-                writeOccurred = true;
-                writePending = outbound.hasRemaining();
-                outbound.compact();
-            }
-        }
-    }
-
-    /**
-     * Indicates whether the stream has bytes to be written to the channel.
-     *
-     * @return true if there are bytes to be written
-     */
-    boolean isWritePending() {
-        synchronized (this) {
-            return writePending;
-        }
-    }
-
-
-    /**
-     * Indicates whether data has been written but not flushed yet.
-     *
-     * @return true if flush is required
-     */
-    boolean isFlushRequired() {
-        synchronized (this) {
-            return outbound.position() > 0;
-        }
-    }
-
-    /**
-     * Attempts to flush data, internal stream state and channel availability
-     * permitting. Invoked by the driver I/O loop during handling of writable
-     * selection key.
-     * <p>
-     * Resets the internal state flags {@code writeOccurred} and
-     * {@code writePending}.
-     * </p>
-     * @throws IOException if implicit flush failed
-     */
-    void flushIfPossible() throws IOException {
-        synchronized (this) {
-            writePending = false;
-            writeOccurred = false;
-            if (outbound.position() > 0) {
-                flush();
-            }
-        }
-        key.interestOps(SelectionKey.OP_READ);
-    }
-
-    /**
-     * Attempts to flush data, internal stream state and channel availability
-     * permitting and if other writes are not pending. Invoked by the driver
-     * I/O loop prior to entering select wait. Resets the internal
-     * {@code writeOccurred} state flag.
-     *
-     * @throws IOException if implicit flush failed
-     */
-    void flushIfWriteNotPending() throws IOException {
-        synchronized (this) {
-            writeOccurred = false;
-            if (!writePending && outbound.position() > 0) {
-                flush();
-            }
-        }
-        if (isWritePending()) {
-            key.interestOps(key.interestOps() | SelectionKey.OP_WRITE);
-        }
-    }
-
-    /**
-     * Doubles the size of the outbound buffer.
-     */
-    private void doubleSize() {
-        ByteBuffer newBuffer = allocateDirect(outbound.capacity() * 2);
-        outbound.flip();
-        newBuffer.put(outbound);
-        outbound = newBuffer;
-    }
-
-    /**
-     * Returns the maximum number of milliseconds the stream is allowed
-     * without any read/write operations.
-     *
-     * @return number if millis of permissible idle time
-     */
-    protected int maxIdleMillis() {
-        return maxIdleMillis;
-    }
-
-
-    /**
-     * Returns true if the given stream has gone stale.
-     *
-     * @return true if the stream is stale
-     */
-    boolean isStale() {
-        return currentTimeMillis() - lastActiveTime > maxIdleMillis() && key != null;
-    }
-
-    /**
-     * Returns the inbound bytes counter.
-     *
-     * @return inbound bytes counter
-     */
-    public Counter bytesIn() {
-        return bytesIn;
-    }
-
-    /**
-     * Returns the outbound bytes counter.
-     *
-     * @return outbound bytes counter
-     */
-    public Counter bytesOut() {
-        return bytesOut;
-    }
-
-    /**
-     * Returns the inbound messages counter.
-     *
-     * @return inbound messages counter
-     */
-    public Counter messagesIn() {
-        return messagesIn;
-    }
-
-    /**
-     * Returns the outbound messages counter.
-     *
-     * @return outbound messages counter
-     */
-    public Counter messagesOut() {
-        return messagesOut;
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.IOException;
-import java.nio.channels.Selector;
-
-import static com.google.common.base.Preconditions.checkArgument;
-import static java.lang.System.currentTimeMillis;
-
-/**
- * Abstraction of an I/O processing loop based on an NIO selector.
- */
-public abstract class SelectorLoop implements Runnable {
-
-    protected final Logger log = LoggerFactory.getLogger(getClass());
-
-    /**
-     * Selector used by this loop to pace the I/O operations.
-     */
-    protected final Selector selector;
-
-    /**
-     * Selection operations timeout; specified in millis.
-     */
-    protected long selectTimeout;
-
-    /**
-     * Retains the error that caused the loop to exit prematurely.
-     */
-    private Throwable error;
-
-    // State indicator
-    private enum State { STARTING, STARTED, STOPPING, STOPPED };
-    private volatile State state = State.STOPPED;
-
-    /**
-     * Creates a new selector loop with the given selection timeout.
-     *
-     * @param selectTimeout selection timeout; specified in millis
-     * @throws IOException if the backing selector cannot be opened
-     */
-    public SelectorLoop(long selectTimeout) throws IOException {
-        checkArgument(selectTimeout > 0, "Timeout must be positive");
-        this.selectTimeout = selectTimeout;
-        this.selector = openSelector();
-    }
-
-    /**
-     * Opens a new selector for the use by the loop.
-     *
-     * @return newly open selector
-     * @throws IOException if the backing selector cannot be opened
-     */
-    protected Selector openSelector() throws IOException {
-        return Selector.open();
-    }
-
-    /**
-     * Indicates that the loop is marked to run.
-     * @return true if the loop is marked to run
-     */
-    protected boolean isRunning() {
-        return state == State.STARTED || state == State.STARTING;
-    }
-
-    /**
-     * Returns the error, if there was one, that caused the loop to terminate
-     * prematurely.
-     *
-     * @return error or null if there was none
-     */
-    public Throwable getError() {
-        return error;
-    }
-
-    /**
-     * Contains the body of the I/O selector loop.
-     *
-     * @throws IOException if an error is encountered while selecting I/O
-     */
-    protected abstract void loop() throws IOException;
-
-    @Override
-    public void run() {
-        error = null;
-        state = State.STARTING;
-        try {
-            loop();
-        } catch (Exception e) {
-            error = e;
-            log.error("Loop aborted", e);
-        }
-        notifyDone();
-    }
-
-    /**
-     * Notifies observers waiting for loop to become ready.
-     */
-    protected synchronized void notifyReady() {
-        state = State.STARTED;
-        notifyAll();
-    }
-
-    /**
-     * Triggers loop shutdown.
-     */
-    public void shutdown() {
-        // Mark the loop as no longer running and wake up the selector.
-        state = State.STOPPING;
-        selector.wakeup();
-    }
-
-    /**
-     * Notifies observers waiting for loop to fully stop.
-     */
-    private synchronized void notifyDone() {
-        state = State.STOPPED;
-        notifyAll();
-    }
-
-    /**
-     * Waits for the loop execution to start.
-     *
-     * @param timeout number of milliseconds to wait
-     * @return true if loop started in time
-     */
-    public final synchronized boolean awaitStart(long timeout) {
-        long max = currentTimeMillis() + timeout;
-        while (state != State.STARTED && (currentTimeMillis() < max)) {
-            try {
-                wait(timeout);
-            } catch (InterruptedException e) {
-                throw new RuntimeException("Interrupted", e);
-            }
-        }
-        return state == State.STARTED;
-    }
-
-    /**
-     * Waits for the loop execution to stop.
-     *
-     * @param timeout number of milliseconds to wait
-     * @return true if loop finished in time
-     */
-    public final synchronized boolean awaitStop(long timeout) {
-        long max = currentTimeMillis() + timeout;
-        while (state != State.STOPPED && (currentTimeMillis() < max)) {
-            try {
-                wait(timeout);
-            } catch (InterruptedException e) {
-                throw new RuntimeException("Interrupted", e);
-            }
-        }
-        return state == State.STOPPED;
-    }
-
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-/**
- * Mechanism to transfer messages over network using IO loop and
- * message stream, backed by NIO byte buffers.
- */
-package org.onlab.nio;

-/*
- * Copyright 2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio.service;
-
-import java.io.IOException;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.SelectionKey;
-import java.util.List;
-import java.util.function.Consumer;
-
-import org.onlab.nio.IOLoop;
-import org.onlab.nio.MessageStream;
-
-/**
- * IOLoop for transporting DefaultMessages.
- */
-public class DefaultIOLoop extends IOLoop<DefaultMessage, DefaultMessageStream> {
-
-    public static final int SELECT_TIMEOUT_MILLIS = 500;
-    private static final int MAX_IDLE_TIMEOUT_MILLIS = 1000;
-    private static final int BUFFER_SIZE = 1024 * 1024;
-    private final Consumer<DefaultMessage> consumer;
-
-    public DefaultIOLoop(Consumer<DefaultMessage> consumer) throws IOException {
-        this(SELECT_TIMEOUT_MILLIS, consumer);
-    }
-
-    public DefaultIOLoop(long timeout, Consumer<DefaultMessage> consumer) throws IOException {
-        super(timeout);
-        this.consumer = consumer;
-    }
-
-    @Override
-    protected DefaultMessageStream createStream(ByteChannel byteChannel) {
-        return new DefaultMessageStream(this, byteChannel, BUFFER_SIZE, MAX_IDLE_TIMEOUT_MILLIS);
-    }
-
-    @Override
-    protected void processMessages(List<DefaultMessage> messages, MessageStream<DefaultMessage> stream) {
-        messages.forEach(consumer);
-    }
-
-    @Override
-    protected void connect(SelectionKey key) throws IOException {
-        DefaultMessageStream stream = (DefaultMessageStream) key.attachment();
-        try {
-            super.connect(key);
-            stream.connected();
-        } catch (Exception e) {
-            stream.connectFailed(e);
-        }
-    }
-}
\ No newline at end of file

-/*
- * Copyright 2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio.service;
-
-import static com.google.common.base.Preconditions.checkNotNull;
-
-import org.onlab.nio.AbstractMessage;
-import org.onlab.packet.IpAddress;
-import org.onlab.util.ByteArraySizeHashPrinter;
-import org.onosproject.store.cluster.messaging.Endpoint;
-
-import com.google.common.base.Charsets;
-import com.google.common.base.MoreObjects;
-
-/**
- * Default message.
- */
-public class DefaultMessage extends AbstractMessage {
-
-    private long id;
-    private Endpoint sender;
-    private String type;
-    private byte[] payload;
-
-    /**
-     * Creates a new message with the specified data.
-     *
-     * @param id message id
-     * @param type message type
-     * @param sender sender endpoint
-     * @param payload message payload
-     */
-    DefaultMessage(long id, Endpoint sender, String type, byte[] payload) {
-        this.id = id;
-        this.type = checkNotNull(type, "Type cannot be null");
-        this.sender = checkNotNull(sender, "Sender cannot be null");
-        this.payload = checkNotNull(payload, "Payload cannot be null");
-
-        byte[] messageTypeBytes = type.getBytes(Charsets.UTF_8);
-        IpAddress senderIp = sender.host();
-        byte[] ipOctets = senderIp.toOctets();
-
-        length = 25 + ipOctets.length + messageTypeBytes.length + payload.length;
-    }
-
-    /**
-     * Returns message id.
-     *
-     * @return message id
-     */
-    public long id() {
-        return id;
-    }
-
-    /**
-     * Returns message sender.
-     *
-     * @return message sender
-     */
-    public Endpoint sender() {
-        return sender;
-    }
-
-    /**
-     * Returns message type.
-     *
-     * @return message type
-     */
-    public String type() {
-        return type;
-    }
-
-    /**
-     * Returns message payload.
-     *
-     * @return payload
-     */
-    public byte[] payload() {
-        return payload;
-    }
-
-    @Override
-    public String toString() {
-        return MoreObjects.toStringHelper(this)
-                .add("id", id)
-                .add("type", type)
-                .add("sender", sender)
-                .add("payload", ByteArraySizeHashPrinter.of(payload))
-                .toString();
-    }
-}
\ No newline at end of file

-/*
- * Copyright 2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio.service;
-
-import java.nio.ByteBuffer;
-import java.nio.channels.ByteChannel;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.atomic.AtomicInteger;
-
-import org.onlab.nio.IOLoop;
-import org.onlab.nio.MessageStream;
-import org.onlab.packet.IpAddress;
-import org.onlab.packet.IpAddress.Version;
-import org.onosproject.store.cluster.messaging.Endpoint;
-
-import com.google.common.base.Charsets;
-
-/**
- * Default bi-directional message stream for transferring messages to & from the
- * network via two byte buffers.
- */
-public class DefaultMessageStream extends MessageStream<DefaultMessage> {
-
-    private final CompletableFuture<Void> connectFuture = new CompletableFuture<>();
-
-    public DefaultMessageStream(
-            IOLoop<DefaultMessage, ?> loop,
-            ByteChannel byteChannel,
-            int bufferSize,
-            int maxIdleMillis) {
-        super(loop, byteChannel, bufferSize, maxIdleMillis);
-    }
-
-    public CompletableFuture<DefaultMessageStream> connectedFuture() {
-        return connectFuture.thenApply(v -> this);
-    }
-
-    private final AtomicInteger messageLength = new AtomicInteger(-1);
-
-    @Override
-    protected DefaultMessage read(ByteBuffer buffer) {
-        if (messageLength.get() == -1) {
-            // check if we can read the message length.
-            if (buffer.remaining() < Integer.BYTES) {
-                return null;
-            } else {
-                messageLength.set(buffer.getInt());
-            }
-        }
-
-        if (buffer.remaining() < messageLength.get()) {
-            return null;
-        }
-
-        long id = buffer.getLong();
-        Version ipVersion = buffer.get() == 0x0 ? Version.INET : Version.INET6;
-        byte[] octects = new byte[IpAddress.byteLength(ipVersion)];
-        buffer.get(octects);
-        IpAddress senderIp = IpAddress.valueOf(ipVersion, octects);
-        int senderPort = buffer.getInt();
-        int messageTypeByteLength = buffer.getInt();
-        byte[] messageTypeBytes = new byte[messageTypeByteLength];
-        buffer.get(messageTypeBytes);
-        String messageType = new String(messageTypeBytes, Charsets.UTF_8);
-        int payloadLength = buffer.getInt();
-        byte[] payloadBytes = new byte[payloadLength];
-        buffer.get(payloadBytes);
-
-        // reset for next message
-        messageLength.set(-1);
-
-        return new DefaultMessage(id, new Endpoint(senderIp, senderPort), messageType, payloadBytes);
-    }
-
-    @Override
-    protected void write(DefaultMessage message, ByteBuffer buffer) {
-        Endpoint sender = message.sender();
-        byte[] messageTypeBytes = message.type().getBytes(Charsets.UTF_8);
-        IpAddress senderIp = sender.host();
-        byte[] ipOctets = senderIp.toOctets();
-        byte[] payload = message.payload();
-
-        int messageLength = 21 + ipOctets.length + messageTypeBytes.length + payload.length;
-
-        buffer.putInt(messageLength);
-
-        buffer.putLong(message.id());
-
-        if (senderIp.version() == Version.INET) {
-            buffer.put((byte) 0x0);
-        } else {
-            buffer.put((byte) 0x1);
-        }
-        buffer.put(ipOctets);
-
-        // write sender port
-        buffer.putInt(sender.port());
-
-        // write length of message type
-        buffer.putInt(messageTypeBytes.length);
-
-        // write message type bytes
-        buffer.put(messageTypeBytes);
-
-        // write payload length
-        buffer.putInt(payload.length);
-
-        // write payload.
-        buffer.put(payload);
-    }
-
-    /**
-     * Callback invoked when the stream is successfully connected.
-     */
-    public void connected() {
-        connectFuture.complete(null);
-    }
-
-    /**
-     * Callback invoked when the stream fails to connect.
-     * @param cause failure cause
-     */
-    public void connectFailed(Throwable cause) {
-        connectFuture.completeExceptionally(cause);
-    }
-}
\ No newline at end of file

-/*
- * Copyright 2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio.service;
-
-import static org.onlab.util.Tools.groupedThreads;
-
-import java.io.IOException;
-import java.net.InetSocketAddress;
-import java.net.Socket;
-import java.net.SocketAddress;
-import java.nio.channels.ServerSocketChannel;
-import java.nio.channels.SocketChannel;
-import java.util.List;
-import java.util.concurrent.CompletableFuture;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.concurrent.ConcurrentMap;
-import java.util.concurrent.Executor;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.TimeoutException;
-import java.util.concurrent.atomic.AtomicBoolean;
-import java.util.concurrent.atomic.AtomicLong;
-import java.util.function.BiConsumer;
-import java.util.function.BiFunction;
-import java.util.function.Consumer;
-
-import org.apache.commons.pool.KeyedPoolableObjectFactory;
-import org.apache.commons.pool.impl.GenericKeyedObjectPool;
-import org.onlab.nio.AcceptorLoop;
-import org.onlab.nio.SelectorLoop;
-import org.onosproject.store.cluster.messaging.Endpoint;
-import org.onosproject.store.cluster.messaging.MessagingService;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
-import com.google.common.cache.RemovalListener;
-import com.google.common.cache.RemovalNotification;
-import com.google.common.collect.Lists;
-import com.google.common.util.concurrent.MoreExecutors;
-
-/**
- * MessagingService implementation based on IOLoop.
- */
-public class IOLoopMessaging implements MessagingService {
-
-    private final Logger log = LoggerFactory.getLogger(getClass());
-
-    private static final String REPLY_MESSAGE_TYPE = "ONOS_REQUEST_REPLY";
-
-    static final long TIMEOUT = 1000;
-
-    static final boolean SO_NO_DELAY = false;
-    static final int SO_SEND_BUFFER_SIZE = 128 * 1024;
-    static final int SO_RCV_BUFFER_SIZE = 128 * 1024;
-
-    private static final int NUM_WORKERS = 8;
-
-    private AcceptorLoop acceptorLoop;
-    private final ExecutorService acceptorThreadPool =
-            Executors.newSingleThreadExecutor(groupedThreads("onos/nio/messaging", "acceptor"));
-    private final ExecutorService ioThreadPool =
-            Executors.newFixedThreadPool(NUM_WORKERS, groupedThreads("onos/nio/messaging", "io-loop-worker-%d"));
-
-    private final List<DefaultIOLoop> ioLoops = Lists.newArrayList();
-
-    private int lastWorker = -1;
-
-    private final AtomicBoolean started = new AtomicBoolean(false);
-    private Endpoint localEp;
-
-    private GenericKeyedObjectPool<Endpoint, DefaultMessageStream> streams =
-            new GenericKeyedObjectPool<>(new DefaultMessageStreamFactory());
-
-    private final ConcurrentMap<String, Consumer<DefaultMessage>> handlers = new ConcurrentHashMap<>();
-    private final AtomicLong messageIdGenerator = new AtomicLong(0);
-    private final Cache<Long, Callback> responseFutures = CacheBuilder.newBuilder()
-            .removalListener(new RemovalListener<Long, Callback>() {
-                @Override
-                public void onRemoval(RemovalNotification<Long, Callback> entry) {
-                    if (entry.wasEvicted()) {
-                        entry.getValue().completeExceptionally(new TimeoutException("Timedout waiting for reply"));
-                    }
-                }
-            })
-            .build();
-
-    /**
-     * Activates IO Loops.
-     *
-     * @param localEp local end-point
-     * @throws IOException is activation fails
-     */
-    public void start(Endpoint localEp) throws IOException {
-        if (started.get()) {
-            log.warn("IOMessaging is already running at {}", localEp);
-            return;
-        }
-        this.localEp = localEp;
-        streams.setLifo(false);
-        this.acceptorLoop = new DefaultAcceptorLoop(new InetSocketAddress(localEp.host().toString(), localEp.port()));
-
-        for (int i = 0; i < NUM_WORKERS; i++) {
-            ioLoops.add(new DefaultIOLoop(this::dispatchLocally));
-        }
-
-        ioLoops.forEach(ioThreadPool::execute);
-        acceptorThreadPool.execute(acceptorLoop);
-        ioLoops.forEach(loop -> loop.awaitStart(TIMEOUT));
-        acceptorLoop.awaitStart(TIMEOUT);
-        started.set(true);
-    }
-
-    /**
-     * Shuts down IO loops.
-     */
-    public void stop() {
-        if (started.get()) {
-            ioLoops.forEach(SelectorLoop::shutdown);
-            acceptorLoop.shutdown();
-            ioThreadPool.shutdown();
-            acceptorThreadPool.shutdown();
-            started.set(false);
-        }
-    }
-
-
-    @Override
-    public CompletableFuture<Void> sendAsync(Endpoint ep, String type, byte[] payload) {
-        DefaultMessage message = new DefaultMessage(
-                messageIdGenerator.incrementAndGet(),
-                localEp,
-                type,
-                payload);
-        return sendAsync(ep, message);
-    }
-
-    protected CompletableFuture<Void> sendAsync(Endpoint ep, DefaultMessage message) {
-        CompletableFuture<Void> future = new CompletableFuture<>();
-        if (ep.equals(localEp)) {
-            dispatchLocally(message);
-            future.complete(null);
-            return future;
-        }
-
-        DefaultMessageStream stream = null;
-        try {
-            stream = streams.borrowObject(ep);
-            stream.write(message);
-            future.complete(null);
-        } catch (Exception e) {
-            future.completeExceptionally(e);
-        } finally {
-            try {
-                streams.returnObject(ep, stream);
-            } catch (Exception e) {
-                log.warn("Failed to return stream to pool");
-            }
-        }
-        return future;
-    }
-
-    @Override
-    public CompletableFuture<byte[]> sendAndReceive(
-            Endpoint ep,
-            String type,
-            byte[] payload,
-            Executor executor) {
-        CompletableFuture<byte[]> response = new CompletableFuture<>();
-        Callback callback = new Callback(response, executor);
-        Long messageId = messageIdGenerator.incrementAndGet();
-        responseFutures.put(messageId, callback);
-        DefaultMessage message = new DefaultMessage(messageId, localEp, type, payload);
-        return sendAsync(ep, message).whenComplete((r, e) -> {
-            if (e != null) {
-                responseFutures.invalidate(messageId);
-            }
-        }).thenCompose(v -> response);
-    }
-
-    @Override
-    public CompletableFuture<byte[]> sendAndReceive(
-            Endpoint ep,
-            String type,
-            byte[] payload) {
-        return sendAndReceive(ep, type, payload, MoreExecutors.directExecutor());
-    }
-
-    @Override
-    public void registerHandler(String type, BiConsumer<Endpoint, byte[]> handler, Executor executor) {
-        handlers.put(type, message -> executor.execute(() -> handler.accept(message.sender(), message.payload())));
-    }
-
-    @Override
-    public void registerHandler(String type, BiFunction<Endpoint, byte[], byte[]> handler, Executor executor) {
-        handlers.put(type, message -> executor.execute(() -> {
-            byte[] responsePayload = handler.apply(message.sender(), message.payload());
-            if (responsePayload != null) {
-                DefaultMessage response = new DefaultMessage(message.id(),
-                        localEp,
-                        REPLY_MESSAGE_TYPE,
-                        responsePayload);
-                sendAsync(message.sender(), response).whenComplete((result, error) -> {
-                    log.debug("Failed to respond", error);
-                });
-            }
-        }));
-    }
-
-    @Override
-    public void registerHandler(String type, BiFunction<Endpoint, byte[], CompletableFuture<byte[]>> handler) {
-        handlers.put(type, message -> {
-            handler.apply(message.sender(), message.payload()).whenComplete((result, error) -> {
-                if (error == null) {
-                    DefaultMessage response = new DefaultMessage(message.id(),
-                        localEp,
-                        REPLY_MESSAGE_TYPE,
-                        result);
-                    sendAsync(message.sender(), response).whenComplete((r, e) -> {
-                        if (e != null) {
-                            log.debug("Failed to respond", e);
-                        }
-                    });
-                }
-            });
-        });
-    }
-
-    @Override
-    public void unregisterHandler(String type) {
-        handlers.remove(type);
-    }
-
-    protected void dispatchLocally(DefaultMessage message) {
-        String type = message.type();
-        if (REPLY_MESSAGE_TYPE.equals(type)) {
-            try {
-                Callback callback =
-                        responseFutures.getIfPresent(message.id());
-                if (callback != null) {
-                    callback.complete(message.payload());
-                } else {
-                    log.warn("Received a reply for message id:[{}]. "
-                            + " from {}. But was unable to locate the"
-                            + " request handle", message.id(), message.sender());
-                }
-            } finally {
-                responseFutures.invalidate(message.id());
-            }
-            return;
-        }
-        Consumer<DefaultMessage> handler = handlers.get(type);
-        if (handler != null) {
-            handler.accept(message);
-        } else {
-            log.debug("No handler registered for {}", type);
-        }
-    }
-
-    // Get the next worker to which a client should be assigned
-    private synchronized DefaultIOLoop nextWorker() {
-        lastWorker = (lastWorker + 1) % NUM_WORKERS;
-        return ioLoops.get(lastWorker);
-    }
-
-    /**
-     * Initiates open connection request and registers the pending socket
-     * channel with the given IO loop.
-     *
-     * @param loop loop with which the channel should be registered
-     * @throws java.io.IOException if the socket could not be open or connected
-     */
-    private DefaultMessageStream createConnection(Endpoint ep, DefaultIOLoop loop) throws IOException {
-        SocketAddress sa = new InetSocketAddress(ep.host().toString(), ep.port());
-        SocketChannel ch = SocketChannel.open();
-        ch.configureBlocking(false);
-        DefaultMessageStream stream = loop.connectStream(ch);
-        ch.connect(sa);
-        return stream;
-    }
-
-    // Loop for accepting client connections
-    private class DefaultAcceptorLoop extends AcceptorLoop {
-
-        public DefaultAcceptorLoop(SocketAddress address) throws IOException {
-            super(DefaultIOLoop.SELECT_TIMEOUT_MILLIS, address);
-        }
-
-        @Override
-        protected void acceptConnection(ServerSocketChannel channel) throws IOException {
-            SocketChannel sc = channel.accept();
-            sc.configureBlocking(false);
-
-            Socket so = sc.socket();
-            so.setTcpNoDelay(SO_NO_DELAY);
-            so.setReceiveBufferSize(SO_RCV_BUFFER_SIZE);
-            so.setSendBufferSize(SO_SEND_BUFFER_SIZE);
-
-            nextWorker().acceptStream(sc);
-        }
-    }
-
-    private class DefaultMessageStreamFactory implements KeyedPoolableObjectFactory<Endpoint, DefaultMessageStream> {
-
-        @Override
-        public void activateObject(Endpoint endpoint, DefaultMessageStream stream) throws Exception {
-        }
-
-        @Override
-        public void destroyObject(Endpoint ep, DefaultMessageStream stream) throws Exception {
-            stream.close();
-        }
-
-        @Override
-        public DefaultMessageStream makeObject(Endpoint ep) throws Exception {
-            DefaultMessageStream stream = createConnection(ep, nextWorker()).connectedFuture().get();
-            log.info("Established a new connection to {}", ep);
-            return stream;
-        }
-
-        @Override
-        public void passivateObject(Endpoint ep, DefaultMessageStream stream) throws Exception {
-        }
-
-        @Override
-        public boolean validateObject(Endpoint ep, DefaultMessageStream stream) {
-            return stream.isClosed();
-        }
-    }
-
-
-    private final class Callback {
-        private final CompletableFuture<byte[]> future;
-        private final Executor executor;
-
-        public Callback(CompletableFuture<byte[]> future, Executor executor) {
-            this.future = future;
-            this.executor = executor;
-        }
-
-        public void complete(byte[] value) {
-            executor.execute(() -> future.complete(value));
-        }
-
-        public void completeExceptionally(Throwable error) {
-            executor.execute(() -> future.completeExceptionally(error));
-        }
-    }
-}

-/*
- * Copyright 2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-/**
- * Assembly for sending and receiving messages using the I/O loop mechanism.
- */
-package org.onlab.nio.service;
\ No newline at end of file

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.junit.Before;
-
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.TimeUnit;
-
-import static java.util.concurrent.Executors.newSingleThreadExecutor;
-import static org.junit.Assert.fail;
-import static org.onlab.util.Tools.namedThreads;
-
-/**
- * Base class for various NIO loop unit tests.
- */
-public abstract class AbstractLoopTest {
-
-    protected static final long MAX_MS_WAIT = 1500;
-
-    /** Block on specified countdown latch. Return when countdown reaches
-     * zero, or fail the test if the {@value #MAX_MS_WAIT} ms timeout expires.
-     *
-     * @param latch the latch
-     * @param label an identifying label
-     */
-    protected void waitForLatch(CountDownLatch latch, String label) {
-        try {
-            boolean ok = latch.await(MAX_MS_WAIT, TimeUnit.MILLISECONDS);
-            if (!ok) {
-                fail("Latch await timeout! [" + label + "]");
-            }
-        } catch (InterruptedException e) {
-            System.out.println("Latch interrupt [" + label + "] : " + e);
-            fail("Unexpected interrupt");
-        }
-    }
-
-    protected ExecutorService exec;
-
-    @Before
-    public void setUp() {
-        exec = newSingleThreadExecutor(namedThreads("test"));
-    }
-
-}

-/*
- * Copyright 2014-2015 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.junit.Test;
-
-import java.io.IOException;
-import java.net.InetSocketAddress;
-import java.net.SocketAddress;
-import java.nio.channels.ServerSocketChannel;
-import java.util.concurrent.CountDownLatch;
-
-import static org.junit.Assert.assertEquals;
-import static org.onlab.junit.TestTools.delay;
-
-/**
- * Unit tests for AcceptLoop.
- */
-public class AcceptorLoopTest extends AbstractLoopTest {
-
-    private static final int PICK_EPHEMERAL = 0;
-
-    private static final SocketAddress SOCK_ADDR = new InetSocketAddress("127.0.0.1", PICK_EPHEMERAL);
-
-    private static class MyAcceptLoop extends AcceptorLoop {
-        private final CountDownLatch loopStarted = new CountDownLatch(1);
-        private final CountDownLatch loopFinished = new CountDownLatch(1);
-        private final CountDownLatch runDone = new CountDownLatch(1);
-        private final CountDownLatch ceaseLatch = new CountDownLatch(1);
-
-        private int acceptCount = 0;
-
-        MyAcceptLoop() throws IOException {
-            super(500, SOCK_ADDR);
-        }
-
-        @Override
-        protected void acceptConnection(ServerSocketChannel ssc) throws IOException {
-            acceptCount++;
-        }
-
-        @Override
-        public void loop() throws IOException {
-            loopStarted.countDown();
-            super.loop();
-            loopFinished.countDown();
-        }
-
-        @Override
-        public void run() {
-            super.run();
-            runDone.countDown();
-        }
-
-        @Override
-        public void shutdown() {
-            super.shutdown();
-            ceaseLatch.countDown();
-        }
-    }
-
-    @Test
-    public void basic() throws IOException {
-        MyAcceptLoop myAccLoop = new MyAcceptLoop();
-        AcceptorLoop accLoop = myAccLoop;
-        exec.execute(accLoop);
-        waitForLatch(myAccLoop.loopStarted, "loopStarted");
-        delay(200); // take a quick nap
-        accLoop.shutdown();
-        waitForLatch(myAccLoop.loopFinished, "loopFinished");
-        waitForLatch(myAccLoop.runDone, "runDone");
-        assertEquals(0, myAccLoop.acceptCount);
-    }
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.junit.Before;
-import org.junit.Ignore;
-import org.junit.Test;
-
-import java.net.InetAddress;
-import java.util.Random;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import static org.onlab.junit.TestTools.delay;
-
-/**
- * Integration test for the select, accept and IO loops.
- */
-public class IOLoopIntegrationTest {
-
-    private static final int THREADS = 6;
-    private static final int TIMEOUT = 60;
-    private static final int MESSAGE_LENGTH = 128;
-
-    private static final int MILLION = 1000000;
-    private static final int MSG_COUNT = 40 * MILLION;
-
-    @Before
-    public void warmUp() throws Exception {
-        Logger.getLogger("").setLevel(Level.SEVERE);
-        try {
-            runTest(MILLION, MESSAGE_LENGTH, 15);
-        } catch (Throwable e) {
-            System.err.println("Failed warmup but moving on.");
-            e.printStackTrace();
-        }
-    }
-
-    // TODO: this test can not pass in some environments, need to be improved
-    @Ignore
-    @Test
-    public void basic() throws Exception {
-        runTest(MILLION, MESSAGE_LENGTH, TIMEOUT);
-    }
-
-    public void longHaul() throws Exception {
-        runTest(MSG_COUNT, MESSAGE_LENGTH, TIMEOUT);
-    }
-
-    private void runTest(int count, int size, int timeout) throws Exception {
-        // Use a random port to prevent conflicts.
-        int port = IOLoopTestServer.PORT + new Random().nextInt(100);
-
-        InetAddress ip = InetAddress.getLoopbackAddress();
-        IOLoopTestServer server = new IOLoopTestServer(ip, THREADS, size, port);
-        IOLoopTestClient client = new IOLoopTestClient(ip, THREADS, count, size, port);
-
-        server.start();
-        client.start();
-        delay(100); // Pause to allow loops to get going
-
-        client.await(timeout);
-        client.report();
-
-        server.stop();
-        server.report();
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import com.google.common.collect.Lists;
-import org.onlab.util.Counter;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.IOException;
-import java.net.InetAddress;
-import java.net.InetSocketAddress;
-import java.net.SocketAddress;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.SelectionKey;
-import java.nio.channels.SocketChannel;
-import java.text.DecimalFormat;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.FutureTask;
-import java.util.concurrent.Semaphore;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
-
-import static java.lang.String.format;
-import static java.lang.System.nanoTime;
-import static java.lang.System.out;
-import static org.onlab.nio.IOLoopTestServer.PORT;
-import static org.onlab.util.Tools.delay;
-import static org.onlab.util.Tools.namedThreads;
-
-/**
- * Auxiliary test fixture to measure speed of NIO-based channels.
- */
-public class IOLoopTestClient {
-
-    private static Logger log = LoggerFactory.getLogger(IOLoopTestClient.class);
-
-    private final InetAddress ip;
-    private final int port;
-    private final int msgCount;
-    private final int msgLength;
-
-    private final List<CustomIOLoop> iloops = new ArrayList<>();
-    private final ExecutorService ipool;
-    private final ExecutorService wpool;
-
-    Counter messages;
-    Counter bytes;
-    long latencyTotal = 0;
-    long latencyCount = 0;
-
-
-    /**
-     * Main entry point to launch the client.
-     *
-     * @param args command-line arguments
-     * @throws java.io.IOException                     if unable to connect to server
-     * @throws InterruptedException                    if latch wait gets interrupted
-     * @throws java.util.concurrent.ExecutionException if wait gets interrupted
-     * @throws java.util.concurrent.TimeoutException   if timeout occurred while waiting for completion
-     */
-    public static void main(String[] args)
-            throws IOException, InterruptedException, ExecutionException, TimeoutException {
-        startStandalone(args);
-
-        System.exit(0);
-    }
-
-    /**
-     * Starts a standalone IO loop test client.
-     *
-     * @param args command-line arguments
-     */
-    public static void startStandalone(String[] args)
-            throws IOException, InterruptedException, ExecutionException, TimeoutException {
-        InetAddress ip = InetAddress.getByName(args.length > 0 ? args[0] : "127.0.0.1");
-        int wc = args.length > 1 ? Integer.parseInt(args[1]) : 6;
-        int mc = args.length > 2 ? Integer.parseInt(args[2]) : 50 * 1000000;
-        int ml = args.length > 3 ? Integer.parseInt(args[3]) : 128;
-        int to = args.length > 4 ? Integer.parseInt(args[4]) : 60;
-
-        log.info("Setting up client with {} workers sending {} {}-byte messages to {} server... ",
-                 wc, mc, ml, ip);
-        IOLoopTestClient client = new IOLoopTestClient(ip, wc, mc, ml, PORT);
-
-        client.start();
-        delay(500);
-
-        client.await(to);
-        client.report();
-    }
-
-    /**
-     * Creates a speed client.
-     *
-     * @param ip   ip address of server
-     * @param wc   worker count
-     * @param mc   message count to send per client
-     * @param ml   message length in bytes
-     * @param port socket port
-     * @throws java.io.IOException if unable to create IO loops
-     */
-    public IOLoopTestClient(InetAddress ip, int wc, int mc, int ml, int port) throws IOException {
-        this.ip = ip;
-        this.port = port;
-        this.msgCount = mc;
-        this.msgLength = ml;
-        this.wpool = Executors.newFixedThreadPool(wc, namedThreads("worker"));
-        this.ipool = Executors.newFixedThreadPool(wc, namedThreads("io-loop"));
-
-        for (int i = 0; i < wc; i++) {
-            iloops.add(new CustomIOLoop());
-        }
-    }
-
-    /**
-     * Starts the client workers.
-     *
-     * @throws java.io.IOException if unable to open connection
-     */
-    public void start() throws IOException {
-        messages = new Counter();
-        bytes = new Counter();
-
-        // First start up all the IO loops
-        for (CustomIOLoop l : iloops) {
-            ipool.execute(l);
-        }
-
-        // Wait for all of them to get going
-        for (CustomIOLoop l : iloops) {
-            l.awaitStart(1000);
-        }
-
-        // ... and Next open all connections; one-per-loop
-        for (CustomIOLoop l : iloops) {
-            openConnection(l);
-        }
-    }
-
-
-    /**
-     * Initiates open connection request and registers the pending socket
-     * channel with the given IO loop.
-     *
-     * @param loop loop with which the channel should be registered
-     * @throws java.io.IOException if the socket could not be open or connected
-     */
-    private void openConnection(CustomIOLoop loop) throws IOException {
-        SocketAddress sa = new InetSocketAddress(ip, port);
-        SocketChannel ch = SocketChannel.open();
-        ch.configureBlocking(false);
-        loop.connectStream(ch);
-        ch.connect(sa);
-    }
-
-
-    /**
-     * Waits for the client workers to complete.
-     *
-     * @param secs timeout in seconds
-     * @throws java.util.concurrent.ExecutionException if execution failed
-     * @throws InterruptedException                    if interrupt occurred while waiting
-     * @throws java.util.concurrent.TimeoutException   if timeout occurred
-     */
-    public void await(int secs) throws InterruptedException,
-            ExecutionException, TimeoutException {
-        for (CustomIOLoop l : iloops) {
-            if (l.worker.task != null) {
-                l.worker.task.get(secs, TimeUnit.SECONDS);
-                latencyTotal += l.latencyTotal;
-                latencyCount += l.latencyCount;
-            }
-        }
-        messages.freeze();
-        bytes.freeze();
-    }
-
-    /**
-     * Reports on the accumulated throughput and latency.
-     */
-    public void report() {
-        DecimalFormat f = new DecimalFormat("#,##0");
-        out.println(format("Client: %s messages; %s bytes; %s mps; %s MBs; %s ns latency",
-                           f.format(messages.total()), f.format(bytes.total()),
-                           f.format(messages.throughput()),
-                           f.format(bytes.throughput() / (1024 * msgLength)),
-                           f.format(latencyTotal / latencyCount)));
-    }
-
-
-    // Loop for transfer of fixed-length messages
-    private class CustomIOLoop extends IOLoop<TestMessage, TestMessageStream> {
-
-        Worker worker = new Worker();
-        long latencyTotal = 0;
-        long latencyCount = 0;
-
-
-        public CustomIOLoop() throws IOException {
-            super(500);
-        }
-
-
-        @Override
-        protected TestMessageStream createStream(ByteChannel channel) {
-            return new TestMessageStream(msgLength, channel, this);
-        }
-
-        @Override
-        protected synchronized void removeStream(MessageStream<TestMessage> stream) {
-            super.removeStream(stream);
-            messages.add(stream.messagesIn().total());
-            bytes.add(stream.bytesIn().total());
-            stream.messagesOut().reset();
-            stream.bytesOut().reset();
-        }
-
-        @Override
-        protected void processMessages(List<TestMessage> messages,
-                                       MessageStream<TestMessage> stream) {
-            for (TestMessage message : messages) {
-                // TODO: summarize latency data better
-                latencyTotal += nanoTime() - message.requestorTime();
-                latencyCount++;
-            }
-            worker.release(messages.size());
-        }
-
-        @Override
-        protected void connect(SelectionKey key) throws IOException {
-            super.connect(key);
-            TestMessageStream b = (TestMessageStream) key.attachment();
-            Worker w = ((CustomIOLoop) b.loop()).worker;
-            w.pump(b);
-        }
-
-    }
-
-    /**
-     * Auxiliary worker to connect and pump batched messages using blocking I/O.
-     */
-    private class Worker implements Runnable {
-
-        private static final int BATCH_SIZE = 50;
-        private static final int PERMITS = 2 * BATCH_SIZE;
-
-        private TestMessageStream stream;
-        private FutureTask<Worker> task;
-
-        // Stuff to throttle pump
-        private final Semaphore semaphore = new Semaphore(PERMITS);
-        private int msgWritten;
-
-        void pump(TestMessageStream stream) {
-            this.stream = stream;
-            task = new FutureTask<>(this, this);
-            wpool.execute(task);
-        }
-
-        @Override
-        public void run() {
-            try {
-                log.info("Worker started...");
-
-                while (msgWritten < msgCount) {
-                    int size = Math.min(BATCH_SIZE, msgCount - msgWritten);
-                    writeBatch(size);
-                    msgWritten += size;
-                }
-
-                // Now try to get all the permits back before sending poison pill
-                semaphore.acquireUninterruptibly(PERMITS);
-                stream.close();
-
-                log.info("Worker done...");
-
-            } catch (IOException e) {
-                log.error("Worker unable to perform I/O", e);
-            }
-        }
-
-
-        private void writeBatch(int size) throws IOException {
-            // Build a batch of messages
-            List<TestMessage> batch = Lists.newArrayListWithCapacity(size);
-            for (int i = 0; i < size; i++) {
-                batch.add(new TestMessage(msgLength, nanoTime(), 0, stream.padding()));
-            }
-            acquire(size);
-            stream.write(batch);
-        }
-
-
-        // Release permits based on the specified number of message credits
-        private void release(int permits) {
-            semaphore.release(permits);
-        }
-
-        // Acquire permit for a single batch
-        private void acquire(int permits) {
-            semaphore.acquireUninterruptibly(permits);
-        }
-
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import com.google.common.collect.Lists;
-import org.onlab.util.Counter;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.io.IOException;
-import java.net.InetAddress;
-import java.net.InetSocketAddress;
-import java.net.Socket;
-import java.net.SocketAddress;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.ServerSocketChannel;
-import java.nio.channels.SocketChannel;
-import java.text.DecimalFormat;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-
-import static java.lang.String.format;
-import static java.lang.System.out;
-import static org.onlab.util.Tools.delay;
-import static org.onlab.util.Tools.namedThreads;
-
-/**
- * Auxiliary test fixture to measure speed of NIO-based channels.
- */
-public class IOLoopTestServer {
-
-    private static Logger log = LoggerFactory.getLogger(IOLoopTestServer.class);
-
-    private static final int PRUNE_FREQUENCY = 1000;
-
-    static final int PORT = 9876;
-    static final long TIMEOUT = 1000;
-
-    static final boolean SO_NO_DELAY = false;
-    static final int SO_SEND_BUFFER_SIZE = 128 * 1024;
-    static final int SO_RCV_BUFFER_SIZE = 128 * 1024;
-
-    static final DecimalFormat FORMAT = new DecimalFormat("#,##0");
-
-    private final AcceptorLoop aloop;
-    private final ExecutorService apool = Executors.newSingleThreadExecutor(namedThreads("accept"));
-
-    private final List<CustomIOLoop> iloops = new ArrayList<>();
-    private final ExecutorService ipool;
-
-    private final int workerCount;
-    private final int msgLength;
-    private int lastWorker = -1;
-
-    Counter messages;
-    Counter bytes;
-
-    /**
-     * Main entry point to launch the server.
-     *
-     * @param args command-line arguments
-     * @throws java.io.IOException if unable to crate IO loops
-     */
-    public static void main(String[] args) throws IOException {
-        startStandalone(args);
-        System.exit(0);
-    }
-
-    /**
-     * Starts a standalone IO loop test server.
-     *
-     * @param args command-line arguments
-     */
-    public static void startStandalone(String[] args) throws IOException {
-        InetAddress ip = InetAddress.getByName(args.length > 0 ? args[0] : "127.0.0.1");
-        int wc = args.length > 1 ? Integer.parseInt(args[1]) : 6;
-        int ml = args.length > 2 ? Integer.parseInt(args[2]) : 128;
-
-        log.info("Setting up the server with {} workers, {} byte messages on {}... ",
-                 wc, ml, ip);
-        IOLoopTestServer server = new IOLoopTestServer(ip, wc, ml, PORT);
-        server.start();
-
-        // Start pruning clients and keep going until their number goes to 0.
-        int remaining = -1;
-        while (remaining == -1 || remaining > 0) {
-            delay(PRUNE_FREQUENCY);
-            int r = server.prune();
-            remaining = remaining == -1 && r == 0 ? remaining : r;
-        }
-        server.stop();
-    }
-
-    /**
-     * Creates a speed server.
-     *
-     * @param ip   optional ip of the adapter where to bind
-     * @param wc   worker count
-     * @param ml   message length in bytes
-     * @param port listen port
-     * @throws java.io.IOException if unable to create IO loops
-     */
-    public IOLoopTestServer(InetAddress ip, int wc, int ml, int port) throws IOException {
-        this.workerCount = wc;
-        this.msgLength = ml;
-        this.ipool = Executors.newFixedThreadPool(workerCount, namedThreads("io-loop"));
-
-        this.aloop = new CustomAcceptLoop(new InetSocketAddress(ip, port));
-        for (int i = 0; i < workerCount; i++) {
-            iloops.add(new CustomIOLoop());
-        }
-    }
-
-    /**
-     * Start the server IO loops and kicks off throughput tracking.
-     */
-    public void start() {
-        messages = new Counter();
-        bytes = new Counter();
-
-        for (CustomIOLoop l : iloops) {
-            ipool.execute(l);
-        }
-        apool.execute(aloop);
-
-        for (CustomIOLoop l : iloops) {
-            l.awaitStart(TIMEOUT);
-        }
-        aloop.awaitStart(TIMEOUT);
-    }
-
-    /**
-     * Stop the server IO loops and freezes throughput tracking.
-     */
-    public void stop() {
-        aloop.shutdown();
-        for (CustomIOLoop l : iloops) {
-            l.shutdown();
-        }
-
-        for (CustomIOLoop l : iloops) {
-            l.awaitStop(TIMEOUT);
-        }
-        aloop.awaitStop(TIMEOUT);
-
-        messages.freeze();
-        bytes.freeze();
-    }
-
-    /**
-     * Reports on the accumulated throughput and latency.
-     */
-    public void report() {
-        DecimalFormat f = new DecimalFormat("#,##0");
-        out.println(format("Server: %s messages; %s bytes; %s mps; %s MBs",
-                           f.format(messages.total()), f.format(bytes.total()),
-                           f.format(messages.throughput()),
-                           f.format(bytes.throughput() / (1024 * msgLength))));
-    }
-
-    /**
-     * Prunes the IO loops of stale message buffers.
-     *
-     * @return number of remaining IO loops among all workers.
-     */
-    public int prune() {
-        int count = 0;
-        for (CustomIOLoop l : iloops) {
-            count += l.pruneStaleStreams();
-        }
-        return count;
-    }
-
-    // Get the next worker to which a client should be assigned
-    private synchronized CustomIOLoop nextWorker() {
-        lastWorker = (lastWorker + 1) % workerCount;
-        return iloops.get(lastWorker);
-    }
-
-    // Loop for transfer of fixed-length messages
-    private class CustomIOLoop extends IOLoop<TestMessage, TestMessageStream> {
-
-        public CustomIOLoop() throws IOException {
-            super(500);
-        }
-
-        @Override
-        protected TestMessageStream createStream(ByteChannel channel) {
-            return new TestMessageStream(msgLength, channel, this);
-        }
-
-        @Override
-        protected void removeStream(MessageStream<TestMessage> stream) {
-            super.removeStream(stream);
-            messages.add(stream.messagesIn().total());
-            bytes.add(stream.bytesIn().total());
-        }
-
-        @Override
-        protected void processMessages(List<TestMessage> messages,
-                                       MessageStream<TestMessage> stream) {
-            try {
-                stream.write(createResponses(messages));
-            } catch (IOException e) {
-                log.error("Unable to echo messages", e);
-            }
-        }
-
-        private List<TestMessage> createResponses(List<TestMessage> messages) {
-            List<TestMessage> responses = Lists.newArrayListWithCapacity(messages.size());
-            for (TestMessage message : messages) {
-                responses.add(new TestMessage(message.length(), message.requestorTime(),
-                                              System.nanoTime(), message.padding()));
-            }
-            return responses;
-        }
-    }
-
-    // Loop for accepting client connections
-    private class CustomAcceptLoop extends AcceptorLoop {
-
-        public CustomAcceptLoop(SocketAddress address) throws IOException {
-            super(500, address);
-        }
-
-        @Override
-        protected void acceptConnection(ServerSocketChannel channel) throws IOException {
-            SocketChannel sc = channel.accept();
-            sc.configureBlocking(false);
-
-            Socket so = sc.socket();
-            so.setTcpNoDelay(SO_NO_DELAY);
-            so.setReceiveBufferSize(SO_RCV_BUFFER_SIZE);
-            so.setSendBufferSize(SO_SEND_BUFFER_SIZE);
-
-            nextWorker().acceptStream(sc);
-            log.info("Connected client");
-        }
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-
-import java.io.IOException;
-import java.nio.ByteBuffer;
-import java.nio.channels.ByteChannel;
-import java.nio.channels.ClosedChannelException;
-import java.nio.channels.SelectableChannel;
-import java.nio.channels.SelectionKey;
-import java.nio.channels.Selector;
-import java.nio.channels.spi.SelectorProvider;
-import java.util.ArrayList;
-import java.util.List;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNull;
-
-/**
- * Tests of the message message stream implementation.
- */
-public class MessageStreamTest {
-
-    private static final int SIZE = 64;
-    private static final int BIG_SIZE = 32 * 1024;
-
-    private TestMessage message;
-
-    private TestIOLoop loop;
-    private TestByteChannel channel;
-    private TestMessageStream stream;
-    private TestKey key;
-
-    @Before
-    public void setUp() throws IOException {
-        loop = new TestIOLoop();
-        channel = new TestByteChannel();
-        key = new TestKey(channel);
-        stream = loop.createStream(channel);
-        stream.setKey(key);
-        stream.setNonStrict();
-        message = new TestMessage(SIZE, 0, 0, stream.padding());
-    }
-
-    @After
-    public void tearDown() {
-        loop.shutdown();
-        stream.close();
-    }
-
-    // Validates the state of the message stream
-    private void validate(boolean wp, boolean fr, int read, int written) {
-        assertEquals(wp, stream.isWritePending());
-        assertEquals(fr, stream.isFlushRequired());
-        assertEquals(read, channel.readBytes);
-        assertEquals(written, channel.writtenBytes);
-    }
-
-    @Test
-    public void endOfStream() throws IOException {
-        channel.close();
-        List<TestMessage> messages = stream.read();
-        assertNull(messages);
-    }
-
-    @Test
-    public void bufferGrowth() throws IOException {
-        // Create a stream for big messages and test the growth.
-        stream = new TestMessageStream(BIG_SIZE, channel, loop);
-        TestMessage bigMessage = new TestMessage(BIG_SIZE, 0, 0, stream.padding());
-
-        stream.write(bigMessage);
-        stream.write(bigMessage);
-        stream.write(bigMessage);
-        stream.write(bigMessage);
-        stream.write(bigMessage);
-    }
-
-    @Test
-    public void discardBeforeKey() {
-        // Create a stream that does not yet have the key set and discard it.
-        stream = loop.createStream(channel);
-        assertNull(stream.key());
-        stream.close();
-        // There is not key, so nothing to check; we just expect no problem.
-    }
-
-    @Test
-    public void bufferedRead() throws IOException {
-        channel.bytesToRead = SIZE + 4;
-        List<TestMessage> messages = stream.read();
-        assertEquals(1, messages.size());
-        validate(false, false, SIZE + 4, 0);
-
-        channel.bytesToRead = SIZE - 4;
-        messages = stream.read();
-        assertEquals(1, messages.size());
-        validate(false, false, SIZE * 2, 0);
-    }
-
-    @Test
-    public void bufferedWrite() throws IOException {
-        validate(false, false, 0, 0);
-
-        // First write is immediate...
-        stream.write(message);
-        validate(false, false, 0, SIZE);
-
-        // Second and third get buffered...
-        stream.write(message);
-        validate(false, true, 0, SIZE);
-        stream.write(message);
-        validate(false, true, 0, SIZE);
-
-        // Reset write, which will flush if needed; the next write is again buffered
-        stream.flushIfWriteNotPending();
-        validate(false, false, 0, SIZE * 3);
-        stream.write(message);
-        validate(false, true, 0, SIZE * 3);
-
-        // Select reset, which will flush if needed; the next write is again buffered
-        stream.flushIfPossible();
-        validate(false, false, 0, SIZE * 4);
-        stream.write(message);
-        validate(false, true, 0, SIZE * 4);
-        stream.flush();
-        validate(false, true, 0, SIZE * 4);
-    }
-
-    @Test
-    public void bufferedWriteList() throws IOException {
-        validate(false, false, 0, 0);
-
-        // First write is immediate...
-        List<TestMessage> messages = new ArrayList<>();
-        messages.add(message);
-        messages.add(message);
-        messages.add(message);
-        messages.add(message);
-
-        stream.write(messages);
-        validate(false, false, 0, SIZE * 4);
-
-        stream.write(messages);
-        validate(false, true, 0, SIZE * 4);
-
-        stream.flushIfPossible();
-        validate(false, false, 0, SIZE * 8);
-    }
-
-    @Test
-    public void bufferedPartialWrite() throws IOException {
-        validate(false, false, 0, 0);
-
-        // First write is immediate...
-        stream.write(message);
-        validate(false, false, 0, SIZE);
-
-        // Tell test channel to accept only half.
-        channel.bytesToWrite = SIZE / 2;
-
-        // Second and third get buffered...
-        stream.write(message);
-        validate(false, true, 0, SIZE);
-        stream.flushIfPossible();
-        validate(true, true, 0, SIZE + SIZE / 2);
-    }
-
-    @Test
-    public void bufferedPartialWrite2() throws IOException {
-        validate(false, false, 0, 0);
-
-        // First write is immediate...
-        stream.write(message);
-        validate(false, false, 0, SIZE);
-
-        // Tell test channel to accept only half.
-        channel.bytesToWrite = SIZE / 2;
-
-        // Second and third get buffered...
-        stream.write(message);
-        validate(false, true, 0, SIZE);
-        stream.flushIfWriteNotPending();
-        validate(true, true, 0, SIZE + SIZE / 2);
-    }
-
-    @Test
-    public void bufferedReadWrite() throws IOException {
-        channel.bytesToRead = SIZE + 4;
-        List<TestMessage> messages = stream.read();
-        assertEquals(1, messages.size());
-        validate(false, false, SIZE + 4, 0);
-
-        stream.write(message);
-        validate(false, false, SIZE + 4, SIZE);
-
-        channel.bytesToRead = SIZE - 4;
-        messages = stream.read();
-        assertEquals(1, messages.size());
-        validate(false, false, SIZE * 2, SIZE);
-    }
-
-    // Fake IO driver loop
-    private static class TestIOLoop extends IOLoop<TestMessage, TestMessageStream> {
-
-        public TestIOLoop() throws IOException {
-            super(500);
-        }
-
-        @Override
-        protected TestMessageStream createStream(ByteChannel channel) {
-            return new TestMessageStream(SIZE, channel, this);
-        }
-
-        @Override
-        protected void processMessages(List<TestMessage> messages,
-                                       MessageStream<TestMessage> stream) {
-        }
-
-    }
-
-    // Byte channel test fixture
-    private static class TestByteChannel extends SelectableChannel implements ByteChannel {
-
-        private static final int BUFFER_LENGTH = 1024;
-        byte[] bytes = new byte[BUFFER_LENGTH];
-        int bytesToWrite = BUFFER_LENGTH;
-        int bytesToRead = BUFFER_LENGTH;
-        int writtenBytes = 0;
-        int readBytes = 0;
-
-        @Override
-        public int read(ByteBuffer dst) throws IOException {
-            int l = Math.min(dst.remaining(), bytesToRead);
-            if (bytesToRead > 0) {
-                readBytes += l;
-                dst.put(bytes, 0, l);
-            }
-            return l;
-        }
-
-        @Override
-        public int write(ByteBuffer src) throws IOException {
-            int l = Math.min(src.remaining(), bytesToWrite);
-            writtenBytes += l;
-            src.get(bytes, 0, l);
-            return l;
-        }
-
-        @Override
-        public Object blockingLock() {
-            return null;
-        }
-
-        @Override
-        public SelectableChannel configureBlocking(boolean arg0) throws IOException {
-            return null;
-        }
-
-        @Override
-        public boolean isBlocking() {
-            return false;
-        }
-
-        @Override
-        public boolean isRegistered() {
-            return false;
-        }
-
-        @Override
-        public SelectionKey keyFor(Selector arg0) {
-            return null;
-        }
-
-        @Override
-        public SelectorProvider provider() {
-            return null;
-        }
-
-        @Override
-        public SelectionKey register(Selector arg0, int arg1, Object arg2)
-                throws ClosedChannelException {
-            return null;
-        }
-
-        @Override
-        public int validOps() {
-            return 0;
-        }
-
-        @Override
-        protected void implCloseChannel() throws IOException {
-            bytesToRead = -1;
-        }
-
-    }
-
-    // Selection key text fixture
-    private static class TestKey extends SelectionKey {
-
-        private SelectableChannel channel;
-
-        public TestKey(TestByteChannel channel) {
-            this.channel = channel;
-        }
-
-        @Override
-        public void cancel() {
-        }
-
-        @Override
-        public SelectableChannel channel() {
-            return channel;
-        }
-
-        @Override
-        public int interestOps() {
-            return 0;
-        }
-
-        @Override
-        public SelectionKey interestOps(int ops) {
-            return null;
-        }
-
-        @Override
-        public boolean isValid() {
-            return true;
-        }
-
-        @Override
-        public int readyOps() {
-            return 0;
-        }
-
-        @Override
-        public Selector selector() {
-            return null;
-        }
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import java.io.IOException;
-import java.nio.channels.SelectionKey;
-import java.nio.channels.Selector;
-import java.nio.channels.spi.AbstractSelectableChannel;
-import java.nio.channels.spi.AbstractSelector;
-import java.util.Set;
-
-/**
- * A selector instrumented for unit tests.
- */
-public class MockSelector extends AbstractSelector {
-
-    int wakeUpCount = 0;
-
-    /**
-     * Creates a mock selector, specifying null as the SelectorProvider.
-     */
-    public MockSelector() {
-        super(null);
-    }
-
-    @Override
-    public String toString() {
-        return "{MockSelector: wake=" + wakeUpCount + "}";
-    }
-
-    @Override
-    protected void implCloseSelector() throws IOException {
-    }
-
-    @Override
-    protected SelectionKey register(AbstractSelectableChannel ch, int ops,
-                                    Object att) {
-        return null;
-    }
-
-    @Override
-    public Set<SelectionKey> keys() {
-        return null;
-    }
-
-    @Override
-    public Set<SelectionKey> selectedKeys() {
-        return null;
-    }
-
-    @Override
-    public int selectNow() throws IOException {
-        return 0;
-    }
-
-    @Override
-    public int select(long timeout) throws IOException {
-        return 0;
-    }
-
-    @Override
-    public int select() throws IOException {
-        return 0;
-    }
-
-    @Override
-    public Selector wakeup() {
-        wakeUpCount++;
-        return null;
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import static com.google.common.base.Preconditions.checkNotNull;
-
-/**
- * Test message for measuring rate and round-trip latency.
- */
-public class TestMessage extends AbstractMessage {
-
-    private final byte[] padding;
-
-    private final long requestorTime;
-    private final long responderTime;
-
-    /**
-     * Creates a new message with the specified data.
-     *
-     * @param requestorTime requester time
-     * @param responderTime responder time
-     * @param padding       message padding
-     */
-    TestMessage(int length, long requestorTime, long responderTime, byte[] padding) {
-        this.length = length;
-        this.requestorTime = requestorTime;
-        this.responderTime = responderTime;
-        this.padding = checkNotNull(padding, "Padding cannot be null");
-    }
-
-    public long requestorTime() {
-        return requestorTime;
-    }
-
-    public long responderTime() {
-        return responderTime;
-    }
-
-    public byte[] padding() {
-        return padding;
-    }
-
-}

-/*
- * Copyright 2014 Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.onlab.nio;
-
-import java.nio.ByteBuffer;
-import java.nio.channels.ByteChannel;
-
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkState;
-
-/**
- * Fixed-length message transfer buffer.
- */
-public class TestMessageStream extends MessageStream<TestMessage> {
-
-    private static final String E_WRONG_LEN = "Illegal message length: ";
-    private static final long START_TAG = 0xfeedcafedeaddeedL;
-    private static final long END_TAG = 0xbeadcafedeaddeedL;
-    private static final int META_LENGTH = 40;
-
-    private final int length;
-    private boolean isStrict = true;
-
-    public TestMessageStream(int length, ByteChannel ch, IOLoop<TestMessage, ?> loop) {
-        super(loop, ch, 64 * 1024, 500);
-        checkArgument(length >= META_LENGTH, "Length must be greater than header length of 40");
-        this.length = length;
-    }
-
-    void setNonStrict() {
-        isStrict = false;
-    }
-
-    @Override
-    protected TestMessage read(ByteBuffer rb) {
-        if (rb.remaining() < length) {
-            return null;
-        }
-
-        long startTag = rb.getLong();
-        if (isStrict) {
-            checkState(startTag == START_TAG, "Incorrect message start");
-        }
-
-        long size = rb.getLong();
-        long requestorTime = rb.getLong();
-        long responderTime = rb.getLong();
-        byte[] padding = padding();
-        rb.get(padding);
-
-        long endTag = rb.getLong();
-        if (isStrict) {
-            checkState(endTag == END_TAG, "Incorrect message end");
-        }
-
-        return new TestMessage((int) size, requestorTime, responderTime, padding);
-    }
-
-    @Override
-    protected void write(TestMessage message, ByteBuffer wb) {
-        if (message.length() != length) {
-            throw new IllegalArgumentException(E_WRONG_LEN + message.length());
-        }
-
-        wb.putLong(START_TAG);
-        wb.putLong(message.length());
-        wb.putLong(message.requestorTime());
-        wb.putLong(message.responderTime());
-        wb.put(message.padding(), 0, length - META_LENGTH);
-        wb.putLong(END_TAG);
-    }
-
-    public byte[] padding() {
-        return new byte[length - META_LENGTH];
-    }
-}

@@ -34,7 +34,6 @@
     <modules>
     <modules>
         <module>junit</module>
         <module>junit</module>
         <module>misc</module>
         <module>misc</module>
-        <module>nio</module>
         <module>yangutils</module>
         <module>yangutils</module>
         <module>osgi</module>
         <module>osgi</module>
         <module>rest</module>
         <module>rest</module>