Bug 4105: Add public EntityOwnershipService interface

[controller.git] / opendaylight / md-sal / sal-common-api / src / main / java / org / opendaylight / controller / md / sal / common / api / clustering / Entity.java

diff --git a/opendaylight/md-sal/sal-common-api/src/main/java/org/opendaylight/controller/md/sal/common/api/clustering/Entity.java b/opendaylight/md-sal/sal-common-api/src/main/java/org/opendaylight/controller/md/sal/common/api/clustering/Entity.java
new file mode 100644 (file)
index 0000000..3b9f8a4
--- /dev/null
+++ b/opendaylight/md-sal/sal-common-api/src/main/java/org/opendaylight/controller/md/sal/common/api/clustering/Entity.java
@@ -0,0 +1,106 @@
+/*
+ * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+
+package org.opendaylight.controller.md.sal.common.api.clustering;
+
+import com.google.common.base.Preconditions;
+import javax.annotation.Nonnull;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
+
+/**
+ * <p></p>
+ * A clustered Entity is something which is shared by multiple applications across a cluster. An Entity has a type
+ * and an identifier.
+ * </p>
+ * <p>
+ * The type describes the type of the Entity where examples of a type maybe "openflow" or "netconf"
+ * etc. An Entity type could be tied to how exactly an application shares and "owns" an entity. For example we may want
+ * an application which deals with the openflow entity to be assigned ownership of that entity based on a first come
+ * first served basis. On the other hand for netconf entity types we may want applications to gain ownership based on
+ * a load balancing approach. While this mechanism of assigning a ownership acquisition strategy is not finalized the
+ * intention is that the entity type will play a role in determining the strategy and thus should be put in place.
+ * </p>
+ * <p>
+ * The identifier is a YangInstanceIdentifier. The reason for the choice of YangInstanceIdentifier is because it
+ * can easily be used to represent a data node. For example an inventory node represents a shared entity and it is best
+ * referenced by the YangInstanceIdentifier if the inventory node stored in the data store.
+ * </p>
+ */
+public final class Entity {
+
+    private final String type;
+    private final YangInstanceIdentifier id;
+
+    /**
+     * Construct a new Entity
+     *
+     * @param type the type of the entity
+     * @param id the identifier of the entity
+     */
+    public Entity(@Nonnull String type, @Nonnull YangInstanceIdentifier id) {
+        this.type = Preconditions.checkNotNull(type, "type should not be null");
+        this.id = Preconditions.checkNotNull(id, "id should not be null");
+    }
+
+    /**
+     *
+     * @return id of entity
+     */
+    @Nonnull
+    public YangInstanceIdentifier getId(){
+        return id;
+    }
+
+    /**
+     *
+     * @return type of entity
+     */
+    @Nonnull
+    public String getType(){
+        return type;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+
+        if (o == null || getClass() != o.getClass()) {
+            return false;
+        }
+
+        Entity entity = (Entity) o;
+
+        if (!id.equals(entity.id)) {
+            return false;
+        }
+
+        if (!type.equals(entity.type)) {
+            return false;
+        }
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = type != null ? type.hashCode() : 0;
+        result = 31 * result + (id != null ? id.hashCode() : 0);
+        return result;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuilder sb = new StringBuilder("Entity{");
+        sb.append("type='").append(type).append('\'');
+        sb.append(", id=").append(id);
+        sb.append('}');
+        return sb.toString();
+    }
+}