empty frames with no constructor will generate correctly

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/frames/BaseFrame.java

@@ -36,7 +36,7 @@ public class BaseFrame
     private boolean rsv3 = false;
     private OpCode opcode = null;
     private boolean masked = false;
-    private int payloadLength;
+    private int payloadLength = 0;
     private byte mask[];
     private ByteBuffer payload = null;
 
@@ -132,7 +132,7 @@ public class BaseFrame
         rsv3 = false;
         opcode = null;
         masked = false;
-        payloadLength = -1;
+        payloadLength = 0;
         mask = null;
     }
 

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/frames/PingFrame.java

@@ -19,11 +19,11 @@ public class PingFrame extends ControlFrame
     }
 
     /**
-     * Construct Ping Frame from known bytebuffer
+     * Construct Ping Frame from known byte[]
      * 
      * @param payload
      */
-    public PingFrame(ByteBuffer payload)
+    public PingFrame(byte[] payload)
     {
         this();
         setPayload(payload);

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/generator/PingFrameGenerator.java

@@ -15,7 +15,10 @@ public class PingFrameGenerator extends FrameGenerator<PingFrame>
 
     @Override
     public void fillPayload(ByteBuffer buffer, PingFrame ping)
+    {
+        if ( ping.hasPayload() )
         {
             BufferUtil.put(ping.getPayload(),buffer);
         }
+    }
 }

jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/ab/ABCase2.java

@@ -0,0 +1,36 @@
+package org.eclipse.jetty.websocket.ab;
+
+import java.nio.ByteBuffer;
+
+import org.eclipse.jetty.websocket.ByteBufferAssert;
+import org.eclipse.jetty.websocket.api.WebSocketBehavior;
+import org.eclipse.jetty.websocket.api.WebSocketPolicy;
+import org.eclipse.jetty.websocket.frames.PingFrame;
+import org.eclipse.jetty.websocket.generator.Generator;
+import org.junit.Test;
+
+public class ABCase2
+{
+    @Test
+    public void testGenerateEmptyPingCase2_1()
+    {
+        PingFrame pingFrame = new PingFrame();
+        
+        WebSocketPolicy policy = new WebSocketPolicy(WebSocketBehavior.SERVER);
+
+        Generator generator = new Generator(policy);
+        ByteBuffer actual = ByteBuffer.allocate(32);
+        generator.generate(actual, pingFrame);
+
+        ByteBuffer expected = ByteBuffer.allocate(5);
+
+        expected.put(new byte[]
+                { (byte)0x89, (byte)0x00 });
+        
+        actual.flip();
+        expected.flip();
+        
+        ByteBufferAssert.assertEquals("buffers do not match",expected,actual);
+    }
+    
+}