ONOS-7050 Refactored PI translation service and store

The translation store is now able to maintain mappings between
translated entities and specific instances of a PI entry in the network
(i.e. applied to a device).

The translation service has been refactored to allow users to
learn and forget translated entities.

The refactoring of the P4Runtime driver using this service will be
submitted separatelly.

Change-Id: Iaafd87d90232514853ca0dea0115dbae4f6e7886
diff --git a/core/store/dist/src/test/java/org/onosproject/store/pi/impl/DistributedPiTranslationStoreTest.java b/core/store/dist/src/test/java/org/onosproject/store/pi/impl/DistributedPiTranslationStoreTest.java
new file mode 100644
index 0000000..2ba52a2
--- /dev/null
+++ b/core/store/dist/src/test/java/org/onosproject/store/pi/impl/DistributedPiTranslationStoreTest.java
@@ -0,0 +1,153 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * 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.store.pi.impl;
+
+import com.google.common.collect.Lists;
+import org.apache.commons.lang3.RandomUtils;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.pi.runtime.PiEntity;
+import org.onosproject.net.pi.runtime.PiEntityType;
+import org.onosproject.net.pi.runtime.PiHandle;
+import org.onosproject.net.pi.service.PiTranslatable;
+import org.onosproject.net.pi.service.PiTranslatedEntity;
+import org.onosproject.store.service.TestStorageService;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Test for {@link AbstractDistributedPiTranslationStore}.
+ */
+public class DistributedPiTranslationStoreTest {
+
+    private AbstractDistributedPiTranslationStore<PiTranslatable, PiEntity> store;
+
+    private static final int HANDLE_HASH = RandomUtils.nextInt();
+    private static final PiTranslatable PI_TRANSLATABLE =
+            new PiTranslatable() {
+            };
+    private static final PiEntity PI_ENTITY = () -> PiEntityType.TABLE_ENTRY;
+    private static final PiHandle<PiEntity> PI_HANDLE =
+            new PiHandle<PiEntity>(DeviceId.NONE, PI_ENTITY) {
+                @Override
+                public int hashCode() {
+                    return HANDLE_HASH;
+                }
+
+                @Override
+                public boolean equals(Object other) {
+                    return other instanceof PiHandle && other.hashCode() == hashCode();
+                }
+
+                @Override
+                public String toString() {
+                    return String.valueOf(HANDLE_HASH);
+                }
+            };
+    private static final PiTranslatedEntity<PiTranslatable, PiEntity> TRANSLATED_ENTITY =
+            new PiTranslatedEntity<>(PI_TRANSLATABLE, PI_ENTITY, PI_HANDLE);
+
+    /**
+     * Sets up the store and the storage service test harness.
+     */
+    @Before
+    public void setUp() {
+        store = new AbstractDistributedPiTranslationStore<PiTranslatable, PiEntity>() {
+            @Override
+            protected String mapSimpleName() {
+                return "test";
+            }
+        };
+        store.storageService = new TestStorageService();
+        store.setDelegate(event -> {
+        });
+        store.activate();
+    }
+
+    /**
+     * Tests equality of key and value used in other tests.
+     */
+    @Test
+    public void testEquality() {
+        assertEquals(PI_HANDLE, PI_HANDLE);
+        assertEquals(TRANSLATED_ENTITY, TRANSLATED_ENTITY);
+    }
+
+    /**
+     * Test for activate.
+     */
+    @Test
+    public void activate() {
+        assertNotNull(store.storageService);
+        assertTrue("Store must have delegate",
+                   store.hasDelegate());
+        assertTrue("No value should be in the map",
+                   Lists.newArrayList(store.getAll()).isEmpty());
+    }
+
+    /**
+     * Test for deactivate.
+     */
+    @Test(expected = NullPointerException.class)
+    public void deactivate() {
+        store.deactivate();
+        store.getAll();
+    }
+
+    /**
+     * Test of value add or update.
+     */
+    @Test
+    public void addOrUpdate() {
+        store.addOrUpdate(PI_HANDLE, TRANSLATED_ENTITY);
+        assertTrue("Value should be in the map",
+                   store.get(PI_HANDLE) != null);
+        assertTrue("Exactly 1 value should be in the map",
+                   Lists.newArrayList(store.getAll()).size() == 1);
+
+        // Add again, expect 1 value.
+        store.addOrUpdate(PI_HANDLE, TRANSLATED_ENTITY);
+        assertTrue("Exactly 1 value should be in the map",
+                   Lists.newArrayList(store.getAll()).size() == 1);
+    }
+
+    /**
+     * Test of value lookup.
+     */
+    @Test
+    public void lookup() throws Exception {
+        clear();
+        addOrUpdate();
+        assertEquals("Wrong value in the map",
+                     store.get(PI_HANDLE), TRANSLATED_ENTITY);
+    }
+
+    /**
+     * Test of value removal.
+     */
+    @Test
+    public void clear() {
+        store.remove(PI_HANDLE);
+        assertTrue("Value should NOT be in the map",
+                   store.get(PI_HANDLE) == null);
+        assertTrue("No value should be in the map",
+                   Lists.newArrayList(store.getAll()).isEmpty());
+    }
+}