diff --git a/core/api/src/main/java/org/onlab/onos/net/flow/DefaultFlowRule.java b/core/api/src/main/java/org/onlab/onos/net/flow/DefaultFlowRule.java
index 6e59cf5..f31f3c3 100644
--- a/core/api/src/main/java/org/onlab/onos/net/flow/DefaultFlowRule.java
+++ b/core/api/src/main/java/org/onlab/onos/net/flow/DefaultFlowRule.java
@@ -58,7 +58,7 @@
     }
 
     public DefaultFlowRule(DeviceId deviceId, TrafficSelector selector,
-            TrafficTreatment treatement, int priority, ApplicationId appId,
+            TrafficTreatment treatment, int priority, ApplicationId appId,
             int timeout, boolean permanent) {
 
         if (priority < FlowRule.MIN_PRIORITY) {
@@ -68,7 +68,7 @@
         this.deviceId = deviceId;
         this.priority = priority;
         this.selector = selector;
-        this.treatment = treatement;
+        this.treatment = treatment;
         this.appId = appId.id();
         this.timeout = timeout;
         this.permanent = permanent;
diff --git a/core/net/src/test/java/org/onlab/onos/net/flow/DefaultFlowRuleTest.java b/core/net/src/test/java/org/onlab/onos/net/flow/DefaultFlowRuleTest.java
new file mode 100644
index 0000000..cddaf23
--- /dev/null
+++ b/core/net/src/test/java/org/onlab/onos/net/flow/DefaultFlowRuleTest.java
@@ -0,0 +1,166 @@
+/*
+ * Copyright 2014 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.onlab.onos.net.flow;
+
+import org.junit.Test;
+import org.onlab.onos.net.DeviceId;
+import org.onlab.onos.net.intent.IntentTestsMocks;
+
+import com.google.common.testing.EqualsTester;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.onlab.junit.ImmutableClassChecker.assertThatClassIsImmutableBaseClass;
+import static org.onlab.onos.net.NetTestTools.did;
+import static org.onlab.onos.net.NetTestTools.APP_ID;
+
+/**
+ * Unit tests for the default flow rule class.
+ */
+public class DefaultFlowRuleTest {
+    private static final IntentTestsMocks.MockSelector SELECTOR =
+            new IntentTestsMocks.MockSelector();
+    private static final IntentTestsMocks.MockTreatment TREATMENT =
+            new IntentTestsMocks.MockTreatment();
+
+    final FlowRule flowRule1 = new MockFlowRule(1);
+    final FlowRule sameAsFlowRule1 = new MockFlowRule(1);
+    final FlowRule flowRule2 = new MockFlowRule(2);
+    final DefaultFlowRule defaultFlowRule1 = new DefaultFlowRule(flowRule1);
+    final DefaultFlowRule sameAsDefaultFlowRule1 = new DefaultFlowRule(sameAsFlowRule1);
+    final DefaultFlowRule defaultFlowRule2 = new DefaultFlowRule(flowRule2);
+
+    private static class MockFlowRule implements FlowRule {
+
+        int priority;
+        MockFlowRule(int priority) {
+            this.priority = priority;
+        }
+
+        @Override
+        public FlowId id() {
+            return FlowId.valueOf(1);
+        }
+
+        @Override
+        public short appId() {
+            return 0;
+        }
+
+        @Override
+        public int priority() {
+            return priority;
+        }
+
+        @Override
+        public DeviceId deviceId() {
+            return did("1");
+        }
+
+        @Override
+        public TrafficSelector selector() {
+            return SELECTOR;
+        }
+
+        @Override
+        public TrafficTreatment treatment() {
+            return TREATMENT;
+        }
+
+        @Override
+        public int timeout() {
+            return 0;
+        }
+
+        @Override
+        public boolean isPermanent() {
+            return false;
+        }
+
+
+    }
+
+    /**
+     * Checks that the DefaultFlowRule class is immutable but can be inherited
+     * from.
+     */
+    @Test
+    public void testImmutability() {
+        assertThatClassIsImmutableBaseClass(DefaultFlowRule.class);
+    }
+
+    /**
+     * Tests the equals, hashCode and toString methods using Guava EqualsTester.
+     */
+    @Test
+    public void testEquals() {
+        new EqualsTester()
+                .addEqualityGroup(defaultFlowRule1, sameAsDefaultFlowRule1)
+                .addEqualityGroup(defaultFlowRule2)
+                .testEquals();
+    }
+
+    /**
+     * Tests creation of a DefaultFlowRule using a FlowRule constructor.
+     */
+    @Test
+    public void testCreationFromFlowRule() {
+        assertThat(defaultFlowRule1.deviceId(), is(flowRule1.deviceId()));
+        assertThat(defaultFlowRule1.appId(), is(flowRule1.appId()));
+        assertThat(defaultFlowRule1.id(), is(flowRule1.id()));
+        assertThat(defaultFlowRule1.isPermanent(), is(flowRule1.isPermanent()));
+        assertThat(defaultFlowRule1.priority(), is(flowRule1.priority()));
+        assertThat(defaultFlowRule1.selector(), is(flowRule1.selector()));
+        assertThat(defaultFlowRule1.treatment(), is(flowRule1.treatment()));
+        assertThat(defaultFlowRule1.timeout(), is(flowRule1.timeout()));
+    }
+
+    /**
+     * Tests creation of a DefaultFlowRule using a FlowId constructor.
+     */
+    @Test
+    public void testCreationWithFlowId() {
+        final DefaultFlowRule rule =
+                new DefaultFlowRule(did("1"), SELECTOR,
+                        TREATMENT, 22, 33,
+                44, false);
+        assertThat(rule.deviceId(), is(did("1")));
+        assertThat(rule.id().value(), is(33L));
+        assertThat(rule.isPermanent(), is(false));
+        assertThat(rule.priority(), is(22));
+        assertThat(rule.selector(), is(SELECTOR));
+        assertThat(rule.treatment(), is(TREATMENT));
+        assertThat(rule.timeout(), is(44));
+    }
+
+    /**
+     * Tests the creation of a DefaultFlowRule using an AppId constructor.
+     */
+    @Test
+    public void testCreationWithAppId() {
+        final DefaultFlowRule rule =
+                new DefaultFlowRule(did("1"), SELECTOR,
+                        TREATMENT, 22, APP_ID,
+                        44, false);
+        assertThat(rule.deviceId(), is(did("1")));
+        assertThat(rule.isPermanent(), is(false));
+        assertThat(rule.priority(), is(22));
+        assertThat(rule.selector(), is(SELECTOR));
+        assertThat(rule.treatment(), is(TREATMENT));
+        assertThat(rule.timeout(), is(44));
+    }
+}
diff --git a/utils/junit/src/main/java/org/onlab/junit/ImmutableClassChecker.java b/utils/junit/src/main/java/org/onlab/junit/ImmutableClassChecker.java
index 2ac20b7..421a3e9 100644
--- a/utils/junit/src/main/java/org/onlab/junit/ImmutableClassChecker.java
+++ b/utils/junit/src/main/java/org/onlab/junit/ImmutableClassChecker.java
@@ -43,9 +43,9 @@
      * @param clazz the class to check
      * @return true if the given class is a properly specified immutable class.
      */
-    private boolean isImmutableClass(Class<?> clazz) {
+    private boolean isImmutableClass(Class<?> clazz, boolean allowNonFinalClass) {
         // class must be declared final
-        if (!Modifier.isFinal(clazz.getModifiers())) {
+        if (!allowNonFinalClass && !Modifier.isFinal(clazz.getModifiers())) {
             failureReason = "a class that is not final";
             return false;
         }
@@ -113,16 +113,16 @@
     }
 
     /**
-     * Assert that the given class adheres to the utility class rules.
+     * Assert that the given class adheres to the immutable class rules.
      *
      * @param clazz the class to check
      *
-     * @throws java.lang.AssertionError if the class is not a valid
-     *         utility class
+     * @throws java.lang.AssertionError if the class is not an
+     *         immutable class
      */
     public static void assertThatClassIsImmutable(Class<?> clazz) {
         final ImmutableClassChecker checker = new ImmutableClassChecker();
-        if (!checker.isImmutableClass(clazz)) {
+        if (!checker.isImmutableClass(clazz, false)) {
             final Description toDescription = new StringDescription();
             final Description mismatchDescription = new StringDescription();
 
@@ -136,4 +136,31 @@
             throw new AssertionError(reason);
         }
     }
+
+    /**
+     * Assert that the given class adheres to the immutable class rules, but
+     * is not declared final.  Classes that need to be inherited from cannot be
+     * declared final.
+     *
+     * @param clazz the class to check
+     *
+     * @throws java.lang.AssertionError if the class is not an
+     *         immutable class
+     */
+    public static void assertThatClassIsImmutableBaseClass(Class<?> clazz) {
+        final ImmutableClassChecker checker = new ImmutableClassChecker();
+        if (!checker.isImmutableClass(clazz, true)) {
+            final Description toDescription = new StringDescription();
+            final Description mismatchDescription = new StringDescription();
+
+            checker.describeTo(toDescription);
+            checker.describeMismatch(mismatchDescription);
+            final String reason =
+                    "\n" +
+                            "Expected: is \"" + toDescription.toString() + "\"\n" +
+                            "    but : was \"" + mismatchDescription.toString() + "\"";
+
+            throw new AssertionError(reason);
+        }
+    }
 }