ONOS-894 : Implemented GroupProvider

Change-Id: I2755abd433921a420ad545fcf6fef61e90a8b89f

@@ -149,7 +149,7 @@
         <bundle>mvn:org.onosproject/onos-of-provider-device/@ONOS-VERSION</bundle>
         <bundle>mvn:org.onosproject/onos-of-provider-packet/@ONOS-VERSION</bundle>
         <bundle>mvn:org.onosproject/onos-of-provider-flow/@ONOS-VERSION</bundle>
-
+        <bundle>mvn:org.onosproject/onos-of-provider-group/@ONOS-VERSION</bundle>
     </feature>
 
     <feature name="onos-app-tvue" version="@FEATURE-VERSION"

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ 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.
+  -->
+<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>onos-of-providers</artifactId>
+        <version>1.1.0-SNAPSHOT</version>
+        <relativePath>../pom.xml</relativePath>
+    </parent>
+
+    <artifactId>onos-of-provider-group</artifactId>
+    <packaging>bundle</packaging>
+
+    <description>ONOS OpenFlow protocol group provider</description>
+
+</project>
\ 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.onosproject.provider.of.group.impl;
+
+import org.jboss.netty.util.HashedWheelTimer;
+import org.jboss.netty.util.Timeout;
+import org.jboss.netty.util.TimerTask;
+import org.onlab.util.Timer;
+import org.onosproject.openflow.controller.OpenFlowSwitch;
+import org.onosproject.openflow.controller.RoleState;
+import org.projectfloodlight.openflow.protocol.OFGroupDescStatsRequest;
+import org.projectfloodlight.openflow.protocol.OFGroupStatsRequest;
+import org.projectfloodlight.openflow.types.OFGroup;
+import org.slf4j.Logger;
+
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicLong;
+
+import static org.slf4j.LoggerFactory.getLogger;
+
+/*
+ * Sends Group Stats Request and collect the group statistics with a time interval.
+ */
+public class GroupStatsCollector implements TimerTask {
+
+    private final HashedWheelTimer timer = Timer.getTimer();
+    private final OpenFlowSwitch sw;
+    private final Logger log = getLogger(getClass());
+    private final int refreshInterval;
+
+    private Timeout timeout;
+    private final AtomicLong xidCounter = new AtomicLong(1);
+
+    private boolean stopTimer = false;
+
+    /**
+     * Creates a GroupStatsCollector object.
+     *
+     * @param sw Open Flow switch
+     * @param interval time interval for collecting group statistic
+     */
+    public GroupStatsCollector(OpenFlowSwitch sw, int interval) {
+        this.sw = sw;
+        this.refreshInterval = interval;
+    }
+
+    @Override
+    public void run(Timeout timeout) throws Exception {
+        log.trace("Collecting stats for {}", sw.getStringId());
+
+        sendGroupStatistic();
+
+        if (!this.stopTimer) {
+            log.trace("Scheduling stats collection in {} seconds for {}",
+                    this.refreshInterval, this.sw.getStringId());
+            timeout.getTimer().newTimeout(this, refreshInterval,
+                    TimeUnit.SECONDS);
+        }
+    }
+
+    private void sendGroupStatistic() {
+        if (log.isTraceEnabled()) {
+            log.trace("sendGroupStatistics {}:{}", sw.getStringId(), sw.getRole());
+        }
+        if (sw.getRole() != RoleState.MASTER) {
+            return;
+        }
+        Long statsXid = xidCounter.getAndAdd(2);
+        OFGroupStatsRequest statsRequest = sw.factory().buildGroupStatsRequest()
+                .setGroup(OFGroup.ALL)
+                .setXid(statsXid)
+                .build();
+        sw.sendMsg(statsRequest);
+
+        Long descXid = statsXid + 1;
+        OFGroupDescStatsRequest descStatsRequest =
+                sw.factory().buildGroupDescStatsRequest()
+                        .setXid(descXid)
+                        .build();
+        sw.sendMsg(descStatsRequest);
+    }
+
+    /**
+     * Starts the collector.
+     */
+    public void start() {
+        log.info("Staring Group Stats collection thread for {}", sw.getStringId());
+        timeout = timer.newTimeout(this, 1, TimeUnit.SECONDS);
+    }
+
+    /**
+     * Stops the collector.
+     */
+    public void stop() {
+        log.info("Stopping Group Stats collection thread for {}", sw.getStringId());
+        this.stopTimer = true;
+        timeout.cancel();
+    }
+}

@@ -37,6 +37,7 @@
         <module>host</module>
         <module>packet</module>
         <module>flow</module>
+        <module>group</module>
     </modules>
 
     <dependencies>