diff --git a/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/OFPortMapTest.java b/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/OFPortMapTest.java
new file mode 100644
index 0000000..8f31c3b
--- /dev/null
+++ b/java_gen/pre-written/src/test/java/org/projectfloodlight/openflow/types/OFPortMapTest.java
@@ -0,0 +1,54 @@
+package org.projectfloodlight.openflow.types;
+
+import static org.junit.Assert.assertArrayEquals;
+import junit.framework.TestCase;
+
+import org.junit.Test;
+
+public class OFPortMapTest extends TestCase {
+
+    @Test
+    public void testOFPortMap() {
+        Boolean[] on = new Boolean[128];
+        for (int i = 0; i < 128; i++) {
+            on[i] = false;
+        }
+
+        OFPortMap.Builder builder = new OFPortMap.Builder();
+
+        for (int i = 0; i < 128; i += 3) {
+            OFPort p = OFPort.of(i);
+            builder.set(p);
+            on[p.getPortNumber()] = true;
+        }
+
+        // Test that all ports that were added are actually on, and all other ports are off
+        OFPortMap portmap = builder.build();
+        System.out.println(portmap);
+        Boolean[] actual = new Boolean[128];
+        for (int i = 0; i < 128; i++) {
+            actual[i] = false;
+        }
+        for (int i = 0; i < 128; i++) {
+            actual[i] = portmap.isOn(OFPort.of(i));
+        }
+        assertArrayEquals(on, actual);
+
+        // Turn some ports off
+        for (int i = 0; i < 128; i += 7) {
+            on[i] = false;
+            builder.unset(OFPort.of(i));
+        }
+
+        // Test again
+        portmap = builder.build();
+        actual = new Boolean[128];
+        for (int i = 0; i < 128; i++) {
+            actual[i] = false;
+        }
+        for (int i = 0; i < 128; i++) {
+            actual[i] = portmap.isOn(OFPort.of(i));
+        }
+        assertArrayEquals(on, actual);
+    }
+}