[ONOS-5363] Support for virtualization in Provider Scheme

Change-Id: I4b38bbe9144d2d726414497f73eb5c1f022ce53b
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProvider.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProvider.java
new file mode 100644
index 0000000..fa5332d
--- /dev/null
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProvider.java
@@ -0,0 +1,81 @@
+/*
+ * 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.incubator.net.virtual.provider;
+
+import java.util.Objects;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+
+public abstract class AbstractVirtualProvider implements VirtualProvider {
+    private final String scheme;
+    private final String id;
+
+    /**
+     * Creates a provider with the supplied identifier.
+     *
+     * @param scheme provider scheme
+     * @param id provider id
+     */
+    protected AbstractVirtualProvider(String id, String scheme) {
+        this.scheme = scheme;
+        this.id = id;
+    }
+
+    /**
+     * Returns the device URI scheme to which this provider is bound.
+     *
+     * @return device URI scheme
+     */
+    @Override
+    public String scheme() {
+        return this.scheme;
+    }
+
+    /**
+     * Returns the device URI scheme specific id portion.
+     *
+     * @return id
+     */
+    @Override
+    public String id() {
+        return this.id;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(scheme, id);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+        if (obj instanceof AbstractVirtualProvider) {
+            final AbstractVirtualProvider other = (AbstractVirtualProvider) obj;
+            return Objects.equals(this.scheme, other.scheme) &&
+                    Objects.equals(this.id, other.id);
+        }
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        return toStringHelper(this).add("scheme", scheme).add("id", id)
+                .toString();
+    }
+}
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProviderService.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProviderService.java
new file mode 100644
index 0000000..b257d2e
--- /dev/null
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/AbstractVirtualProviderService.java
@@ -0,0 +1,51 @@
+/*
+ * 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.incubator.net.virtual.provider;
+
+import static com.google.common.base.Preconditions.checkState;
+
+public abstract class AbstractVirtualProviderService<P extends VirtualProvider>
+        implements VirtualProviderService {
+
+    private boolean isValid = true;
+    private final P provider;
+
+    protected AbstractVirtualProviderService(P provider) {
+        this.provider = provider;
+    }
+
+    /**
+     * Invalidates this provider service.
+     */
+    public void invalidate() {
+        isValid = false;
+    }
+
+    /**
+     * Checks the validity of this provider service.
+     *
+     * @throws java.lang.IllegalStateException if the service is no longer valid
+     */
+    public void checkValidity() {
+        checkState(isValid, "Provider service is no longer valid");
+    }
+
+    @Override
+    public P provider() {
+        return provider;
+    }
+}
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualFlowRuleProviderRegistry.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualFlowRuleProviderRegistry.java
deleted file mode 100644
index 4d0ea63..0000000
--- a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualFlowRuleProviderRegistry.java
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- * 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.incubator.net.virtual.provider;
-
-/**
- * Abstraction for a flow rule provider registry.
- */
-public interface VirtualFlowRuleProviderRegistry
-        extends VirtualProviderRegistry<VirtualFlowRuleProvider,
-        VirtualFlowRuleProviderService> {
-}
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProvider.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProvider.java
index 0416600..e94215d 100644
--- a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProvider.java
+++ b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProvider.java
@@ -23,4 +23,17 @@
  */
 public interface VirtualProvider {
 
+    /**
+     * Returns the device URI scheme to which this provider is bound.
+     *
+     * @return device URI scheme
+     */
+    String scheme();
+
+    /**
+     * Returns the device URI scheme specific id portion.
+     *
+     * @return id
+     */
+    String id();
 }
diff --git a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProviderRegistry.java b/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProviderRegistry.java
deleted file mode 100644
index 8240139..0000000
--- a/incubator/api/src/main/java/org/onosproject/incubator/net/virtual/provider/VirtualProviderRegistry.java
+++ /dev/null
@@ -1,56 +0,0 @@
-/*
- * 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.incubator.net.virtual.provider;
-
-import java.util.Set;
-
-/** Registry for tracking information virtual providers with the core.
- * @param <P> type of the information virtual provider
- * @param <S> type of the provider virtual service
- */
-
-public interface VirtualProviderRegistry<P extends VirtualProvider,
-            S extends VirtualProviderService<P>> {
-
-    /**
-     * Registers the supplied virtual provider with the virtual core.
-     *
-     * @param provider virtual provider to be registered
-     * @return service for injecting information into core
-     * @throws java.lang.IllegalArgumentException if the provider is registered already
-     */
-    S register(P provider);
-
-    /**
-     * Unregisters the supplied virtual provider.
-     * As a result the previously issued virtual provider service
-     * will be invalidated and any subsequent invocations
-     * of its methods may throw {@link java.lang.IllegalStateException}.
-     * Unregistering a virtual provider that has not been previously registered
-     * result in a no-op.
-     *
-     * @param provider provider to be unregistered
-     */
-    void unregister(P provider);
-
-    /**
-     * Returns a set of currently registered virtual providers.
-     *
-     * @return set of virtual providers
-     */
-    Set<P> getProviders();
-}