[ONOS-7003] Policer implementation

Changes:
- Introduce trafficcontrol package
- Add policer
- Add policer id
- Add policing resource
- Add token bucket
- Add unit tests

Change-Id: I70065d58d3df7033e67a81943ebf60187c33c3e2
diff --git a/core/api/src/test/java/org/onosproject/net/behaviour/trafficcontrol/PolicerIdTest.java b/core/api/src/test/java/org/onosproject/net/behaviour/trafficcontrol/PolicerIdTest.java
new file mode 100644
index 0000000..883f40d
--- /dev/null
+++ b/core/api/src/test/java/org/onosproject/net/behaviour/trafficcontrol/PolicerIdTest.java
@@ -0,0 +1,139 @@
+/*
+ * 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.net.behaviour.trafficcontrol;
+
+import com.google.common.base.Strings;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+import org.onlab.junit.ImmutableClassChecker;
+
+import java.net.URI;
+
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Test class for PolicerId.
+ */
+public class PolicerIdTest {
+
+    // Test scheme
+    private static final String FOO_SCHEME = "foo";
+    // OpenFlow scheme
+    private static final String OF_SCHEME = "of";
+    // Some test ids
+    private static final Short ONE = 1;
+    private static final Short TWO = 15;
+    private static final String A = "A";
+    private static final String LA = "a";
+
+    /**
+     * Test policer id creation from URI.
+     */
+    @Test
+    public void testfromUriCreation() {
+        // Create URI representing the id
+        URI uriOne = URI.create(OF_SCHEME + ":" + Integer.toHexString(ONE));
+        // Create policer id
+        PolicerId one = PolicerId.policerId(uriOne);
+        // Verify proper creation
+        assertThat(one, notNullValue());
+        assertThat(one.id(), is(uriOne.toString().toLowerCase()));
+        assertThat(one.uri(), is(uriOne));
+    }
+
+    /**
+     * Test policer id creation from string.
+     */
+    @Test
+    public void testfromStringCreation() {
+        // Create String representing the id
+        String stringTwo = OF_SCHEME + ":" + Integer.toHexString(TWO);
+        // Create policer id
+        PolicerId two = PolicerId.policerId(stringTwo);
+        // Verify proper creation
+        assertThat(two, notNullValue());
+        assertThat(two.id(), is(stringTwo));
+        assertThat(two.uri(), is(URI.create(stringTwo)));
+    }
+
+    /**
+     * Exception expected to raise when creating a wrong policer id.
+     */
+    @Rule
+    public ExpectedException exceptionWrongId = ExpectedException.none();
+
+    /**
+     * Test wrong creation of a policer id.
+     */
+    @Test
+    public void testWrongCreation() {
+        // Build not allowed string
+        String wrongString = Strings.repeat("x", 1025);
+        // Define expected exception
+        exceptionWrongId.expect(IllegalArgumentException.class);
+        // Create policer id
+        PolicerId.policerId(wrongString);
+    }
+
+    /**
+     * Test equality between policer ids.
+     */
+    @Test
+    public void testEquality() {
+        // Create URI representing the id one
+        URI uriOne = URI.create(OF_SCHEME + ":" + Integer.toHexString(ONE));
+        // Create String representing the id one
+        String stringOne = OF_SCHEME + ":" + Integer.toHexString(ONE);
+        // Create String representing the id two
+        String stringTwo = OF_SCHEME + ":" + Integer.toHexString(TWO);
+        // Create String representing the id A
+        String stringA = FOO_SCHEME + ":" + A;
+        // Create String representing the id LA
+        String stringLA = FOO_SCHEME + ":" + LA;
+        // Create policer id one
+        PolicerId one = PolicerId.policerId(uriOne);
+        // Create policer id one
+        PolicerId copyOfOne = PolicerId.policerId(stringOne);
+        // Verify equality
+        assertEquals(one, copyOfOne);
+        // Create a different policer id
+        PolicerId two = PolicerId.policerId(stringTwo);
+        // Verify not equals
+        assertNotEquals(two, one);
+        assertNotEquals(two, copyOfOne);
+        // Create policer id A
+        PolicerId a = PolicerId.policerId(A);
+        // Create policer id LA
+        PolicerId la = PolicerId.policerId(LA);
+        // Verify not equals
+        assertNotEquals(a, la);
+    }
+
+    /**
+     * Tests immutability of PolicerId.
+     */
+    @Test
+    public void testImmutability() {
+        ImmutableClassChecker.assertThatClassIsImmutable(PolicerId.class);
+    }
+
+}