adding purge option to IntentRemoveCommand

Change-Id: Ic97acd9a8308355cd3135ea5df0a470b3579106e
diff --git a/core/api/src/main/java/org/onosproject/net/intent/IntentService.java b/core/api/src/main/java/org/onosproject/net/intent/IntentService.java
index 0d14a38..b86d793 100644
--- a/core/api/src/main/java/org/onosproject/net/intent/IntentService.java
+++ b/core/api/src/main/java/org/onosproject/net/intent/IntentService.java
@@ -112,4 +112,11 @@
      * @param listener listener to be removed
      */
     void removeListener(IntentListener listener);
+
+    /**
+     * Purges a specific intent from the system if it is FAILED or WITHDRAWN.
+     *
+     * @param key key of the intent to purge
+     */
+    void purge(Key key);
 }
diff --git a/core/api/src/main/java/org/onosproject/net/intent/IntentStore.java b/core/api/src/main/java/org/onosproject/net/intent/IntentStore.java
index 5cfae17..2bf1ef1 100644
--- a/core/api/src/main/java/org/onosproject/net/intent/IntentStore.java
+++ b/core/api/src/main/java/org/onosproject/net/intent/IntentStore.java
@@ -109,4 +109,10 @@
      * @return pending intents
      */
     Iterable<Intent> getPending();
+
+    /** Purges a specific intent from the system if it is FAILED or WITHDRAWN.
+     *
+     * @param key key of the intent to purge
+     */
+    void purge(Key key);
 }
diff --git a/core/api/src/test/java/org/onosproject/net/intent/FakeIntentManager.java b/core/api/src/test/java/org/onosproject/net/intent/FakeIntentManager.java
index 3d2475b..f232cbc 100644
--- a/core/api/src/test/java/org/onosproject/net/intent/FakeIntentManager.java
+++ b/core/api/src/test/java/org/onosproject/net/intent/FakeIntentManager.java
@@ -230,6 +230,11 @@
         listeners.remove(listener);
     }
 
+    @Override
+    public void purge(Key key) {
+        // FIXME implement this
+    }
+
     private void dispatch(IntentEvent event) {
         for (IntentListener listener : listeners) {
             listener.event(event);
diff --git a/core/api/src/test/java/org/onosproject/net/intent/IntentServiceAdapter.java b/core/api/src/test/java/org/onosproject/net/intent/IntentServiceAdapter.java
index d100121..2d912eb 100644
--- a/core/api/src/test/java/org/onosproject/net/intent/IntentServiceAdapter.java
+++ b/core/api/src/test/java/org/onosproject/net/intent/IntentServiceAdapter.java
@@ -76,4 +76,9 @@
     public void removeListener(IntentListener listener) {
 
     }
+
+    @Override
+    public void purge(Key key) {
+
+    }
 }
diff --git a/core/net/src/main/java/org/onosproject/net/intent/impl/IntentManager.java b/core/net/src/main/java/org/onosproject/net/intent/impl/IntentManager.java
index 1993729..ed1552a 100644
--- a/core/net/src/main/java/org/onosproject/net/intent/impl/IntentManager.java
+++ b/core/net/src/main/java/org/onosproject/net/intent/impl/IntentManager.java
@@ -193,6 +193,11 @@
     }
 
     @Override
+    public void purge(Key key) {
+        store.purge(key);
+    }
+
+    @Override
     public <T extends Intent> void registerCompiler(Class<T> cls, IntentCompiler<T> compiler) {
         compilerRegistry.registerCompiler(cls, compiler);
     }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/intent/impl/GossipIntentStore.java b/core/store/dist/src/main/java/org/onosproject/store/intent/impl/GossipIntentStore.java
index 4bc0ed0..bbdbdb7 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/intent/impl/GossipIntentStore.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/intent/impl/GossipIntentStore.java
@@ -278,6 +278,14 @@
                 .collect(Collectors.toList());
     }
 
+    @Override
+    public void purge(Key key) {
+        IntentData data = currentMap.get(key);
+        if (data.state() == WITHDRAWN || data.state() == FAILED) {
+            currentMap.remove(key, data);
+        }
+    }
+
     private void notifyDelegateIfNotNull(IntentEvent event) {
         if (event != null) {
             notifyDelegate(event);
diff --git a/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleIntentStore.java b/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleIntentStore.java
index 0a4fcb5..25ff1fb 100644
--- a/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleIntentStore.java
+++ b/core/store/trivial/src/main/java/org/onosproject/store/trivial/impl/SimpleIntentStore.java
@@ -253,4 +253,12 @@
                 .map(IntentData::intent)
                 .collect(Collectors.toList());
     }
+
+    @Override
+    public void purge(Key key) {
+        IntentData data = current.get(key);
+        if (data.state() == IntentState.WITHDRAWN || data.state() == IntentState.FAILED) {
+            current.remove(key, data);
+        }
+    }
 }