Implementation of the DomainService

Change-Id: I012c31d113fbcc12d4c35cb10d11d7be4cd83458
diff --git a/core/net/src/main/java/org/onosproject/net/domain/impl/DomainManager.java b/core/net/src/main/java/org/onosproject/net/domain/impl/DomainManager.java
new file mode 100644
index 0000000..29802bb
--- /dev/null
+++ b/core/net/src/main/java/org/onosproject/net/domain/impl/DomainManager.java
@@ -0,0 +1,95 @@
+/*
+ * Copyright 2016-present 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.net.domain.impl;
+
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.domain.DomainId;
+import org.onosproject.net.domain.DomainService;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.HashSet;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Exposes domain topology elements and listen for updates of such elements.
+ */
+@Component(immediate = true)
+@Service
+public class DomainManager implements DomainService {
+
+    private static final String DOMAIN_ID = "domainId";
+    private static final String LOCAL_DOMAIN = "local";
+    private final Logger log = LoggerFactory.getLogger(getClass());
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceService deviceService;
+
+    @Activate
+    public void activate() {
+
+        log.info("Started");
+    }
+
+    @Deactivate
+    public void deactivate() {
+        log.info("Stopped");
+    }
+
+    @Override
+    public Set<DomainId> getDomainIds() {
+        Set<DomainId> domIds = new HashSet<>();
+        deviceService.getAvailableDevices().forEach(dev ->
+                domIds.add(getAnnotatedDomainId(dev)));
+        return domIds;
+    }
+
+    @Override
+    public Set<DeviceId> getDeviceIds(DomainId domainId) {
+        Set<DeviceId> domainIds = new HashSet<>();
+        deviceService.getAvailableDevices().forEach(dev -> {
+            if (getAnnotatedDomainId(dev).equals(domainId)) {
+                domainIds.add(dev.id());
+            }
+        });
+        return domainIds;
+    }
+
+    @Override
+    public DomainId getDomain(DeviceId deviceId) {
+        checkNotNull(deviceId);
+        return checkNotNull(getAnnotatedDomainId(deviceService.getDevice(deviceId)));
+    }
+
+    private DomainId getAnnotatedDomainId(Device device) {
+        if (!device.annotations().keys().contains(DOMAIN_ID)) {
+            return DomainId.LOCAL;
+        } else {
+            return DomainId.domainId(
+                    device.annotations().value(DOMAIN_ID));
+        }
+    }
+}
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diff --git a/core/net/src/main/java/org/onosproject/net/domain/impl/package-info.java b/core/net/src/main/java/org/onosproject/net/domain/impl/package-info.java
index 4ef383f..73d2f22 100644
--- a/core/net/src/main/java/org/onosproject/net/domain/impl/package-info.java
+++ b/core/net/src/main/java/org/onosproject/net/domain/impl/package-info.java
@@ -15,6 +15,6 @@
  */
 
 /**
- * Implementation of the domain manager.
+ * Implementation of the domain management.
  */
 package org.onosproject.net.domain.impl;
\ No newline at end of file