PortNumber also backed by port name

Change-Id: Id47781be714bf1efe7d008c8e97ab172177a85f9

@@ -15,10 +15,10 @@
  */
 package org.onosproject.net;
 
-import java.util.Objects;
-
 import com.google.common.primitives.UnsignedLongs;
 
+import java.util.Objects;
+
 /**
  * Representation of a port number.
  */
@@ -48,10 +48,17 @@ public final class PortNumber {
     public static final PortNumber CONTROLLER = new PortNumber(CONTROLLER_NUMBER);
 
     private final long number;
+    private final String name;
 
     // Public creation is prohibited
     private PortNumber(long number) {
         this.number = number;
+        this.name = UnsignedLongs.toString(number);
+    }
+
+    private PortNumber(long number, String name) {
+        this.number = number;
+        this.name = name;
     }
 
     /**
@@ -75,6 +82,17 @@ public final class PortNumber {
     }
 
     /**
+     * Returns the port number representing the specified long value and name.
+     *
+     * @param number port number as long value
+     * @param name port name as string value
+     * @return port number
+     */
+    public static PortNumber portNumber(long number, String name) {
+        return new PortNumber(number, name);
+    }
+
+    /**
      * Indicates whether or not this port number is a reserved logical one or
      * whether it corresponds to a normal physical port of a device or NIC.
      *
@@ -115,7 +133,7 @@ public final class PortNumber {
     @Override
     public String toString() {
         if (!isLogical()) {
-            return UnsignedLongs.toString(number);
+            return name;
         } else {
             return decodeLogicalPort();
         }

@@ -15,12 +15,11 @@
  */
 package org.onosproject.net;
 
-import static org.junit.Assert.assertEquals;
-import static org.onosproject.net.PortNumber.portNumber;
-
+import com.google.common.testing.EqualsTester;
 import org.junit.Test;
 
-import com.google.common.testing.EqualsTester;
+import static org.junit.Assert.assertEquals;
+import static org.onosproject.net.PortNumber.portNumber;
 
 /**
  * Test of the port number.
@@ -30,9 +29,8 @@ public class PortNumberTest {
     @Test
     public void basics() {
         new EqualsTester()
-        .addEqualityGroup(portNumber(123),
-                portNumber("123"))
-                .addEqualityGroup(portNumber(321))
+                .addEqualityGroup(portNumber(123), portNumber("123"))
+                .addEqualityGroup(portNumber(321), portNumber(321, "LIM-3-2-1"))
                 .testEquals();
     }