Merge branch 'master' of ssh://gerrit.onlab.us:29418/onos-next

@@ -6,7 +6,7 @@
 
 
     <parent>
     <parent>
         <groupId>org.onlab.onos</groupId>
         <groupId>org.onlab.onos</groupId>
-        <artifactId>onos-net</artifactId>
+        <artifactId>onos-core</artifactId>
         <version>1.0.0-SNAPSHOT</version>
         <version>1.0.0-SNAPSHOT</version>
         <relativePath>../pom.xml</relativePath>
         <relativePath>../pom.xml</relativePath>
     </parent>
     </parent>

 package org.onlab.onos.net;
 package org.onlab.onos.net;
 
 
+import org.onlab.packet.IPv4;
+import org.onlab.packet.MACAddress;
+
+import java.util.Set;
+
 /**
 /**
  * Abstraction of an end-station host on the network, essentially a NIC.
  * Abstraction of an end-station host on the network, essentially a NIC.
  */
  */
 public interface Host extends Element {
 public interface Host extends Element {
 
 
-    // MAC, IP(s), optional VLAN ID
+    /**
+     * Host identification.
+     *
+     * @return host id
+     */
+    HostId id();
+
+    /**
+     * Returns the host MAC address.
+     *
+     * @return mac address
+     */
+    MACAddress mac();
 
 
+    /**
+     * Returns set of IP addresses currently bound to the host MAC address.
+     *
+     * @return set of IP addresses; empty if no IP address is bound
+     */
+    Set<IPv4> ipAddresses();
 
 
     /**
     /**
      * Returns the most recent host location where the host attaches to the
      * Returns the most recent host location where the host attaches to the
@@ -16,6 +39,6 @@ public interface Host extends Element {
      */
      */
     HostLocation location();
     HostLocation location();
 
 
-    // list of recent locations?
+    // TODO: explore capturing list of recent locations to aid in mobility
 
 
 }
 }

 package org.onlab.onos.net;
 package org.onlab.onos.net;
 
 
+import org.onlab.packet.MACAddress;
+
 import java.net.URI;
 import java.net.URI;
 
 
 /**
 /**
@@ -16,6 +18,7 @@ public final class HostId extends ElementId {
      * Creates a device id using the supplied URI.
      * Creates a device id using the supplied URI.
      *
      *
      * @param uri device URI
      * @param uri device URI
+     * @return host identifier
      */
      */
     public static HostId hostId(URI uri) {
     public static HostId hostId(URI uri) {
         return new HostId(uri);
         return new HostId(uri);
@@ -25,9 +28,23 @@ public final class HostId extends ElementId {
      * Creates a device id using the supplied URI string.
      * Creates a device id using the supplied URI string.
      *
      *
      * @param string device URI string
      * @param string device URI string
+     * @return host identifier
      */
      */
     public static HostId hostId(String string) {
     public static HostId hostId(String string) {
         return hostId(URI.create(string));
         return hostId(URI.create(string));
     }
     }
 
 
+    /**
+     * Creates a device id using the supplied MAC & VLAN ID.
+     *
+     * @param mac    mac address
+     * @param vlanId vlan identifier
+     * @return host identifier
+     */
+    // FIXME: replace vlanId long with a rich data-type, e.g. VLanId or something like that
+    public static HostId hostId(MACAddress mac, long vlanId) {
+        // FIXME: use more efficient means of encoding
+        return hostId("nic" + ":" + mac + "/" + vlanId);
+    }
+
 }
 }

@@ -105,7 +105,7 @@ public class DeviceEvent extends AbstractEvent<DeviceEvent.Type, Device> {
      *
      *
      * @return port subject or null if the event is not port specific.
      * @return port subject or null if the event is not port specific.
      */
      */
-    Port port() {
+    public Port port() {
         return port;
         return port;
     }
     }
 
 

@@ -23,6 +23,11 @@ public class HostEvent extends AbstractEvent<HostEvent.Type, Host> {
         HOST_REMOVED,
         HOST_REMOVED,
 
 
         /**
         /**
+         * Signifies that host data changed, e.g. IP address
+         */
+        HOST_UPDATED,
+
+        /**
          * Signifies that a host location has changed.
          * Signifies that a host location has changed.
          */
          */
         HOST_MOVED
         HOST_MOVED

 package org.onlab.onos.net.host;
 package org.onlab.onos.net.host;
 
 
+import org.onlab.onos.net.HostId;
 import org.onlab.onos.net.provider.ProviderService;
 import org.onlab.onos.net.provider.ProviderService;
 
 
 /**
 /**
@@ -11,15 +12,16 @@ public interface HostProviderService extends ProviderService<HostProvider> {
      * Notifies the core when a host has been detected on a network along with
      * Notifies the core when a host has been detected on a network along with
      * information that identifies the hoot location.
      * information that identifies the hoot location.
      *
      *
+     * @param hostId          id of the host that been detected
      * @param hostDescription description of host and its location
      * @param hostDescription description of host and its location
      */
      */
-    void hostDetected(HostDescription hostDescription);
+    void hostDetected(HostId hostId, HostDescription hostDescription);
 
 
     /**
     /**
      * Notifies the core when a host is no longer detected on a network.
      * Notifies the core when a host is no longer detected on a network.
      *
      *
-     * @param hostDescription description of host
+     * @param hostId id of the host that vanished
      */
      */
-    void hostVanished(HostDescription hostDescription);
+    void hostVanished(HostId hostId);
 
 
 }
 }

@@ -2,8 +2,10 @@ package org.onlab.onos.net.host;
 
 
 import org.onlab.onos.net.ConnectPoint;
 import org.onlab.onos.net.ConnectPoint;
 import org.onlab.onos.net.DeviceId;
 import org.onlab.onos.net.DeviceId;
-import org.onlab.onos.net.ElementId;
 import org.onlab.onos.net.Host;
 import org.onlab.onos.net.Host;
+import org.onlab.onos.net.HostId;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.MACAddress;
 
 
 import java.util.Set;
 import java.util.Set;
 
 
@@ -13,6 +15,13 @@ import java.util.Set;
 public interface HostService {
 public interface HostService {
 
 
     /**
     /**
+     * Returns the number of end-station hosts known to the system.
+     *
+     * @return number of end-station hosts
+     */
+    public int getHostCount();
+
+    /**
      * Returns a collection of all end-station hosts.
      * Returns a collection of all end-station hosts.
      *
      *
      * @return collection of hosts
      * @return collection of hosts
@@ -25,12 +34,32 @@ public interface HostService {
      * @param hostId host identifier
      * @param hostId host identifier
      * @return host or null if one with the given identifier is not known
      * @return host or null if one with the given identifier is not known
      */
      */
-    Host getHost(ElementId hostId); // TODO: change to HostId
+    Host getHost(HostId hostId);
+
+    /**
+     * Returns the set of hosts that belong to the specified VLAN.
+     *
+     * @param vlanId vlan identifier
+     * @return set of hosts in the given vlan id
+     */
+    // FIXME: change long to VLanId
+    Set<Host> getHostsByVlan(long vlanId);
 
 
-    // TODO: determine which ones make sense or which we care to support
-    // Set<Host> getHostsByVlan(VlanId vlan);
-    // Set<Host> getHostsByMac(MacAddress mac);
-    // Set<Host> getHostsByIp(IpAddress ip);
+    /**
+     * Returns the set of hosts that have the specified MAC address.
+     *
+     * @param mac mac address
+     * @return set of hosts with the given mac
+     */
+    Set<Host> getHostsByMac(MACAddress mac);
+
+    /**
+     * Returns the set of hosts that have the specified IP address.
+     *
+     * @param ip ip address
+     * @return set of hosts with the given IP
+     */
+    Set<Host> getHostsByIp(IPv4 ip);
 
 
     /**
     /**
      * Returns the set of hosts whose most recent location is the specified
      * Returns the set of hosts whose most recent location is the specified

@@ -11,14 +11,14 @@
         <relativePath>../pom.xml</relativePath>
         <relativePath>../pom.xml</relativePath>
     </parent>
     </parent>
 
 
-    <artifactId>onos-net</artifactId>
+    <artifactId>onos-core</artifactId>
     <packaging>pom</packaging>
     <packaging>pom</packaging>
 
 
     <description>ONOS Core root project</description>
     <description>ONOS Core root project</description>
 
 
     <modules>
     <modules>
         <module>api</module>
         <module>api</module>
-        <module>core</module>
+        <module>trivial</module>
     </modules>
     </modules>
 
 
     <dependencies>
     <dependencies>

@@ -6,19 +6,15 @@
 
 
     <parent>
     <parent>
         <groupId>org.onlab.onos</groupId>
         <groupId>org.onlab.onos</groupId>
-        <artifactId>onos-net</artifactId>
+        <artifactId>onos-core</artifactId>
         <version>1.0.0-SNAPSHOT</version>
         <version>1.0.0-SNAPSHOT</version>
         <relativePath>../pom.xml</relativePath>
         <relativePath>../pom.xml</relativePath>
     </parent>
     </parent>
 
 
-    <artifactId>onos-core</artifactId>
-    <packaging>pom</packaging>
-
-    <description>ONOS network control core subsystems</description>
+    <artifactId>onos-core-trivial</artifactId>
+    <packaging>bundle</packaging>
 
 
-    <modules>
-        <module>trivial</module>
-    </modules>
+    <description>ONOS network control trivial implementations of core subsystems</description>
 
 
     <dependencies>
     <dependencies>
         <dependency>
         <dependency>
@@ -26,10 +22,6 @@
             <artifactId>onos-api</artifactId>
             <artifactId>onos-api</artifactId>
         </dependency>
         </dependency>
         <dependency>
         <dependency>
-            <groupId>org.slf4j</groupId>
-            <artifactId>slf4j-api</artifactId>
-        </dependency>
-        <dependency>
             <groupId>org.apache.felix</groupId>
             <groupId>org.apache.felix</groupId>
             <artifactId>org.apache.felix.scr.annotations</artifactId>
             <artifactId>org.apache.felix.scr.annotations</artifactId>
         </dependency>
         </dependency>

@@ -110,21 +110,6 @@ public class SimpleDeviceManager
     }
     }
 
 
     @Override
     @Override
-    public void addListener(DeviceListener listener) {
-        listenerRegistry.addListener(listener);
-    }
-
-    @Override
-    public void removeListener(DeviceListener listener) {
-        listenerRegistry.removeListener(listener);
-    }
-
-    @Override
-    protected DeviceProviderService createProviderService(DeviceProvider provider) {
-        return new InternalDeviceProviderService(provider);
-    }
-
-    @Override
     public void setRole(DeviceId deviceId, MastershipRole newRole) {
     public void setRole(DeviceId deviceId, MastershipRole newRole) {
         checkNotNull(deviceId, DEVICE_ID_NULL);
         checkNotNull(deviceId, DEVICE_ID_NULL);
         checkNotNull(newRole, ROLE_NULL);
         checkNotNull(newRole, ROLE_NULL);
@@ -143,8 +128,26 @@ public class SimpleDeviceManager
     public void removeDevice(DeviceId deviceId) {
     public void removeDevice(DeviceId deviceId) {
         checkNotNull(deviceId, DEVICE_ID_NULL);
         checkNotNull(deviceId, DEVICE_ID_NULL);
         DeviceEvent event = store.removeDevice(deviceId);
         DeviceEvent event = store.removeDevice(deviceId);
+        if (event != null) {
+            log.info("Device {} administratively removed", deviceId);
             post(event);
             post(event);
         }
         }
+    }
+
+    @Override
+    public void addListener(DeviceListener listener) {
+        listenerRegistry.addListener(listener);
+    }
+
+    @Override
+    public void removeListener(DeviceListener listener) {
+        listenerRegistry.removeListener(listener);
+    }
+
+    @Override
+    protected DeviceProviderService createProviderService(DeviceProvider provider) {
+        return new InternalDeviceProviderService(provider);
+    }
 
 
     // Personalized device provider service issued to the supplied provider.
     // Personalized device provider service issued to the supplied provider.
     private class InternalDeviceProviderService extends AbstractProviderService<DeviceProvider>
     private class InternalDeviceProviderService extends AbstractProviderService<DeviceProvider>
@@ -159,12 +162,12 @@ public class SimpleDeviceManager
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkNotNull(deviceDescription, DEVICE_DESCRIPTION_NULL);
             checkNotNull(deviceDescription, DEVICE_DESCRIPTION_NULL);
             checkValidity();
             checkValidity();
-            log.info("Device {} connected", deviceId);
             DeviceEvent event = store.createOrUpdateDevice(provider().id(),
             DeviceEvent event = store.createOrUpdateDevice(provider().id(),
                                                            deviceId, deviceDescription);
                                                            deviceId, deviceDescription);
 
 
             // If there was a change of any kind, trigger role selection process.
             // If there was a change of any kind, trigger role selection process.
             if (event != null) {
             if (event != null) {
+                log.info("Device {} connected", deviceId);
                 Device device = event.subject();
                 Device device = event.subject();
                 provider().roleChanged(device, store.getRole(device.id()));
                 provider().roleChanged(device, store.getRole(device.id()));
                 post(event);
                 post(event);
@@ -175,17 +178,18 @@ public class SimpleDeviceManager
         public void deviceDisconnected(DeviceId deviceId) {
         public void deviceDisconnected(DeviceId deviceId) {
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkValidity();
             checkValidity();
-            log.info("Device {} disconnected", deviceId);
             DeviceEvent event = store.markOffline(deviceId);
             DeviceEvent event = store.markOffline(deviceId);
+            if (event != null) {
+                log.info("Device {} disconnected", deviceId);
                 post(event);
                 post(event);
             }
             }
+        }
 
 
         @Override
         @Override
         public void updatePorts(DeviceId deviceId, List<PortDescription> portDescriptions) {
         public void updatePorts(DeviceId deviceId, List<PortDescription> portDescriptions) {
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkNotNull(deviceId, DEVICE_ID_NULL);
             checkNotNull(portDescriptions, "Port descriptions list cannot be null");
             checkNotNull(portDescriptions, "Port descriptions list cannot be null");
             checkValidity();
             checkValidity();
-            log.info("Device {} ports updated", deviceId);
             List<DeviceEvent> events = store.updatePorts(deviceId, portDescriptions);
             List<DeviceEvent> events = store.updatePorts(deviceId, portDescriptions);
             for (DeviceEvent event : events) {
             for (DeviceEvent event : events) {
                 post(event);
                 post(event);
@@ -199,11 +203,12 @@ public class SimpleDeviceManager
             checkValidity();
             checkValidity();
             DeviceEvent event = store.updatePortStatus(deviceId, portDescription);
             DeviceEvent event = store.updatePortStatus(deviceId, portDescription);
             if (event != null) {
             if (event != null) {
-                log.info("Device {} port status changed", deviceId);
-            }
+                log.info("Device {} port {} status changed", deviceId,
+                         event.port().number());
                 post(event);
                 post(event);
             }
             }
         }
         }
+    }
 
 
     // Posts the specified event to the local event dispatcher.
     // Posts the specified event to the local event dispatcher.
     private void post(DeviceEvent event) {
     private void post(DeviceEvent event) {

@@ -28,8 +28,7 @@ import static com.google.common.base.Preconditions.checkArgument;
 import static org.onlab.onos.net.device.DeviceEvent.Type.*;
 import static org.onlab.onos.net.device.DeviceEvent.Type.*;
 
 
 /**
 /**
- * Manages inventory of infrastructure devices using trivial in-memory
- * implementation.
+
  */
  */
 class SimpleDeviceStore {
 class SimpleDeviceStore {
 
 

@@ -8,16 +8,26 @@ import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
 import org.apache.felix.scr.annotations.Service;
 import org.onlab.onos.event.AbstractListenerRegistry;
 import org.onlab.onos.event.AbstractListenerRegistry;
 import org.onlab.onos.event.EventDeliveryService;
 import org.onlab.onos.event.EventDeliveryService;
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Host;
+import org.onlab.onos.net.HostId;
 import org.onlab.onos.net.host.HostDescription;
 import org.onlab.onos.net.host.HostDescription;
 import org.onlab.onos.net.host.HostEvent;
 import org.onlab.onos.net.host.HostEvent;
 import org.onlab.onos.net.host.HostListener;
 import org.onlab.onos.net.host.HostListener;
 import org.onlab.onos.net.host.HostProvider;
 import org.onlab.onos.net.host.HostProvider;
 import org.onlab.onos.net.host.HostProviderRegistry;
 import org.onlab.onos.net.host.HostProviderRegistry;
 import org.onlab.onos.net.host.HostProviderService;
 import org.onlab.onos.net.host.HostProviderService;
+import org.onlab.onos.net.host.HostService;
 import org.onlab.onos.net.provider.AbstractProviderRegistry;
 import org.onlab.onos.net.provider.AbstractProviderRegistry;
 import org.onlab.onos.net.provider.AbstractProviderService;
 import org.onlab.onos.net.provider.AbstractProviderService;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.MACAddress;
 import org.slf4j.Logger;
 import org.slf4j.Logger;
 
 
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkNotNull;
 import static org.slf4j.LoggerFactory.getLogger;
 import static org.slf4j.LoggerFactory.getLogger;
 
 
 /**
 /**
@@ -27,13 +37,16 @@ import static org.slf4j.LoggerFactory.getLogger;
 @Service
 @Service
 public class SimpleHostManager
 public class SimpleHostManager
         extends AbstractProviderRegistry<HostProvider, HostProviderService>
         extends AbstractProviderRegistry<HostProvider, HostProviderService>
-        implements HostProviderRegistry {
+        implements HostService, HostProviderRegistry {
 
 
+    public static final String HOST_ID_NULL = "Host ID cannot be null";
     private final Logger log = getLogger(getClass());
     private final Logger log = getLogger(getClass());
 
 
     private final AbstractListenerRegistry<HostEvent, HostListener>
     private final AbstractListenerRegistry<HostEvent, HostListener>
             listenerRegistry = new AbstractListenerRegistry<>();
             listenerRegistry = new AbstractListenerRegistry<>();
 
 
+    private final SimpleHostStore store = new SimpleHostStore();
+
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     private EventDeliveryService eventDispatcher;
     private EventDeliveryService eventDispatcher;
 
 
@@ -55,8 +68,64 @@ public class SimpleHostManager
         return new InternalHostProviderService(provider);
         return new InternalHostProviderService(provider);
     }
     }
 
 
+    @Override
+    public int getHostCount() {
+        return store.getHostCount();
+    }
+
+    @Override
+    public Iterable<Host> getHosts() {
+        return store.getHosts();
+    }
+
+    @Override
+    public Host getHost(HostId hostId) {
+        checkNotNull(hostId, HOST_ID_NULL);
+        return store.getHost(hostId);
+    }
+
+    @Override
+    public Set<Host> getHostsByVlan(long vlanId) {
+        return store.getHosts(vlanId);
+    }
+
+    @Override
+    public Set<Host> getHostsByMac(MACAddress mac) {
+        checkNotNull(mac, "MAC address cannot be null");
+        return store.getHosts(mac);
+    }
+
+    @Override
+    public Set<Host> getHostsByIp(IPv4 ip) {
+        checkNotNull(ip, "IP address cannot be null");
+        return store.getHosts(ip);
+    }
+
+    @Override
+    public Set<Host> getConnectedHosts(ConnectPoint connectPoint) {
+        checkNotNull(connectPoint, "Connection point cannot be null");
+        return store.getConnectedHosts(connectPoint);
+    }
+
+    @Override
+    public Set<Host> getConnectedHosts(DeviceId deviceId) {
+        checkNotNull(deviceId, "Device ID cannot be null");
+        return store.getConnectedHosts(deviceId);
+    }
+
+    @Override
+    public void addListener(HostListener listener) {
+        listenerRegistry.addListener(listener);
+    }
+
+    @Override
+    public void removeListener(HostListener listener) {
+        listenerRegistry.removeListener(listener);
+    }
+
     // Personalized host provider service issued to the supplied provider.
     // Personalized host provider service issued to the supplied provider.
-    private class InternalHostProviderService extends AbstractProviderService<HostProvider>
+    private class InternalHostProviderService
+            extends AbstractProviderService<HostProvider>
             implements HostProviderService {
             implements HostProviderService {
 
 
         InternalHostProviderService(HostProvider provider) {
         InternalHostProviderService(HostProvider provider) {
@@ -64,13 +133,34 @@ public class SimpleHostManager
         }
         }
 
 
         @Override
         @Override
-        public void hostDetected(HostDescription hostDescription) {
-            log.info("Host {} detected", hostDescription);
+        public void hostDetected(HostId hostId, HostDescription hostDescription) {
+            checkNotNull(hostId, HOST_ID_NULL);
+            checkValidity();
+            HostEvent event = store.createOrUpdateHost(provider().id(), hostId,
+                                                       hostDescription);
+            if (event != null) {
+                log.info("Host {} detected", hostId);
+                post(event);
+            }
         }
         }
 
 
         @Override
         @Override
-        public void hostVanished(HostDescription hostDescription) {
-            log.info("Host {} vanished", hostDescription);
+        public void hostVanished(HostId hostId) {
+            checkNotNull(hostId, HOST_ID_NULL);
+            checkValidity();
+            HostEvent event = store.removeHost(hostId);
+            if (event != null) {
+                log.info("Host {} vanished", hostId);
+                post(event);
+            }
         }
         }
     }
     }
+
+    // Posts the specified event to the local event dispatcher.
+    private void post(HostEvent event) {
+        if (event != null && eventDispatcher != null) {
+            eventDispatcher.post(event);
+        }
+    }
+
 }
 }

+package org.onlab.onos.net.trivial.impl;
+
+import org.onlab.onos.net.ConnectPoint;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.Host;
+import org.onlab.onos.net.HostId;
+import org.onlab.onos.net.host.HostDescription;
+import org.onlab.onos.net.host.HostEvent;
+import org.onlab.onos.net.provider.ProviderId;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.MACAddress;
+
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Manages inventory of end-station hosts using trivial in-memory
+ * implementation.
+ */
+public class SimpleHostStore {
+
+    private final Map<HostId, Host> hosts = new ConcurrentHashMap<>();
+
+    /**
+     * Creates a new host or updates the existing one based on the specified
+     * description.
+     *
+     * @param providerId      provider identification
+     * @param hostId          host identification
+     * @param hostDescription host description data
+     * @return appropriate event or null if no change resulted
+     */
+    HostEvent createOrUpdateHost(ProviderId providerId, HostId hostId,
+                                 HostDescription hostDescription) {
+        return null;
+    }
+
+    /**
+     * Removes the specified host from the inventory.
+     *
+     * @param hostId host identification
+     * @return remove even or null if host was not found
+     */
+    HostEvent removeHost(HostId hostId) {
+        return null;
+    }
+
+    /**
+     * Returns the number of hosts in the store.
+     *
+     * @return host count
+     */
+    int getHostCount() {
+        return hosts.size();
+    }
+
+    /**
+     * Returns a collection of all hosts in the store.
+     *
+     * @return iterable collection of all hosts
+     */
+    Iterable<Host> getHosts() {
+        return null;
+    }
+
+    /**
+     * Returns the host with the specified identifer.
+     *
+     * @param hostId host identification
+     * @return host or null if not found
+     */
+    Host getHost(HostId hostId) {
+        return null;
+    }
+
+    /**
+     * Returns the set of all hosts within the specified VLAN.
+     *
+     * @param vlanId vlan id
+     * @return set of hosts in the vlan
+     */
+    Set<Host> getHosts(long vlanId) {
+        return null;
+    }
+
+    /**
+     * Returns the set of hosts with the specified MAC address.
+     *
+     * @param mac mac address
+     * @return set of hosts with the given mac
+     */
+    Set<Host> getHosts(MACAddress mac) {
+        return null;
+    }
+
+    /**
+     * Returns the set of hosts with the specified IP address.
+     *
+     * @param ip ip address
+     * @return set of hosts with the given IP
+     */
+    Set<Host> getHosts(IPv4 ip) {
+        return null;
+    }
+
+    /**
+     * Returns the set of hosts whose location falls on the given connection point.
+     *
+     * @param connectPoint connection point
+     * @return set of hosts
+     */
+    Set<Host> getConnectedHosts(ConnectPoint connectPoint) {
+        return null;
+    }
+
+    /**
+     * Returns the set of hosts whose location falls on the given device.
+     *
+     * @param deviceId infrastructure device identifier
+     * @return set of hosts
+     */
+    public Set<Host> getConnectedHosts(DeviceId deviceId) {
+        return null;
+    }
+
+}

@@ -66,11 +66,6 @@ implements LinkService, LinkAdminService, LinkProviderRegistry {
     }
     }
 
 
     @Override
     @Override
-    protected LinkProviderService createProviderService(LinkProvider provider) {
-        return new InternalLinkProviderService(provider);
-    }
-
-    @Override
     public int getLinkCount() {
     public int getLinkCount() {
         return store.getLinkCount();
         return store.getLinkCount();
     }
     }
@@ -145,6 +140,11 @@ implements LinkService, LinkAdminService, LinkProviderRegistry {
         listenerRegistry.removeListener(listener);
         listenerRegistry.removeListener(listener);
     }
     }
 
 
+    @Override
+    protected LinkProviderService createProviderService(LinkProvider provider) {
+        return new InternalLinkProviderService(provider);
+    }
+
     // Personalized link provider service issued to the supplied provider.
     // Personalized link provider service issued to the supplied provider.
     private class InternalLinkProviderService extends AbstractProviderService<LinkProvider>
     private class InternalLinkProviderService extends AbstractProviderService<LinkProvider>
     implements LinkProviderService {
     implements LinkProviderService {

@@ -53,6 +53,8 @@ public class SimpleTopologyManager
     private final AbstractListenerRegistry<TopologyEvent, TopologyListener>
     private final AbstractListenerRegistry<TopologyEvent, TopologyListener>
             listenerRegistry = new AbstractListenerRegistry<>();
             listenerRegistry = new AbstractListenerRegistry<>();
 
 
+    private final SimpleTopologyStore store = new SimpleTopologyStore();
+
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     private EventDeliveryService eventDispatcher;
     private EventDeliveryService eventDispatcher;
 
 

+package org.onlab.onos.net.trivial.impl;
+
+/**
+ * Manages inventory of topology snapshots using trivial in-memory
+ * implementation.
+ */
+public class SimpleTopologyStore {
+}

-<?xml version="1.0" encoding="UTF-8"?>
-<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.onlab.onos</groupId>
-        <artifactId>onos-core</artifactId>
-        <version>1.0.0-SNAPSHOT</version>
-        <relativePath>../pom.xml</relativePath>
-    </parent>
-
-    <artifactId>onos-core-trivial</artifactId>
-    <packaging>bundle</packaging>
-
-    <description>ONOS network control trivial implementations of core subsystems</description>
-
-</project>

@@ -14,7 +14,7 @@
     <modules>
     <modules>
         <module>tools/build/conf</module>
         <module>tools/build/conf</module>
         <module>utils</module>
         <module>utils</module>
-        <module>net</module>
+        <module>core</module>
         <module>web</module>
         <module>web</module>
         <module>cli</module>
         <module>cli</module>
         <module>providers</module>
         <module>providers</module>