GUI -- added getAsString() to TableModel.Row.
- Moved cell-related classes to new package.
- Created base classes for cell comparator and formatter.
- Created IntComparator and HexFormatter.

Change-Id: I3861bf3e0ca738a2d6eab9c70174db53f22960f8
diff --git a/core/api/src/test/java/org/onosproject/ui/table/cell/IntComparatorTest.java b/core/api/src/test/java/org/onosproject/ui/table/cell/IntComparatorTest.java
new file mode 100644
index 0000000..2b45b3f
--- /dev/null
+++ b/core/api/src/test/java/org/onosproject/ui/table/cell/IntComparatorTest.java
@@ -0,0 +1,72 @@
+/*
+ * Copyright 2015 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.ui.table.cell;
+
+import org.junit.Test;
+import org.onosproject.ui.table.CellComparator;
+
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Unit tests for {@link IntComparator}.
+ */
+public class IntComparatorTest {
+
+    private CellComparator cmp = new IntComparator();
+
+    @Test
+    public void twoNulls() {
+        assertTrue("two nulls", cmp.compare(null, null) == 0);
+    }
+
+    @Test
+    public void nullVsNegValue() {
+        assertTrue("null vs neg value", cmp.compare(null, -5) < 0);
+    }
+
+    @Test
+    public void nullVsPosValue() {
+        assertTrue("null vs pos value", cmp.compare(null, 5) < 0);
+    }
+
+    @Test
+    public void negValueVsNull() {
+        assertTrue("neg value vs null", cmp.compare(-5, null) > 0);
+    }
+
+    @Test
+    public void posValueVsNull() {
+        assertTrue("pos value vs null", cmp.compare(5, null) > 0);
+    }
+
+
+    @Test
+    public void smallVsBig() {
+        assertTrue("small vs big", cmp.compare(25, 75) < 0);
+    }
+
+    @Test
+    public void bigVsSmall() {
+        assertTrue("big vs small", cmp.compare(75, 25) > 0);
+    }
+
+    @Test
+    public void sameValue() {
+        assertTrue("same value", cmp.compare(50, 50) == 0);
+    }
+}