Fleshing out WebSocketPing impl

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/api/io/WebSocketBlockingConnection.java

@@ -33,7 +33,7 @@ public class WebSocketBlockingConnection
         }
         else
         {
-            throw new IllegalArgumentException("Unsupported implementation of WebSocketConnection");
+            throw new IllegalArgumentException("WebSocketConnection must implement internal RawConnection interface");
         }
         this.bufferPool = this.conn.getBufferPool();
         this.policy = conn.getPolicy();

jetty-websocket/websocket-core/src/main/java/org/eclipse/jetty/websocket/api/io/WebSocketPing.java

@@ -1,19 +1,61 @@
 package org.eclipse.jetty.websocket.api.io;
 
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.util.concurrent.ExecutionException;
+
+import org.eclipse.jetty.io.ByteBufferPool;
+import org.eclipse.jetty.util.FutureCallback;
 import org.eclipse.jetty.websocket.api.WebSocketConnection;
+import org.eclipse.jetty.websocket.api.WebSocketPolicy;
+import org.eclipse.jetty.websocket.frames.PingFrame;
+import org.eclipse.jetty.websocket.generator.Generator;
+import org.eclipse.jetty.websocket.io.RawConnection;
 
 public class WebSocketPing
 {
-    private WebSocketConnection conn;
+    private RawConnection conn;
+    private ByteBufferPool bufferPool;
+    private WebSocketPolicy policy;
+    private Generator generator;
 
     public WebSocketPing(WebSocketConnection conn)
     {
-        this.conn = conn;
+        if (conn instanceof RawConnection)
+        {
+            this.conn = (RawConnection)conn;
+        }
+        else
+        {
+            throw new IllegalArgumentException("WebSocketConnection must implement internal RawConnection interface");
+        }
+        this.bufferPool = this.conn.getBufferPool();
+        this.policy = conn.getPolicy();
+        this.generator = new Generator(this.policy);
     }
 
-    public void sendPing(byte buf[], int offset, int len)
+    public void sendPing(byte data[]) throws IOException
     {
-        // TODO: implement
-        // TODO: should this block and wait for a pong? (how?)
+        PingFrame frame = new PingFrame(data);
+        ByteBuffer buf = bufferPool.acquire(policy.getBufferSize(),false);
+        try
+        {
+            generator.generate(buf,frame);
+            FutureCallback<Void> blocking = new FutureCallback<>();
+            this.conn.writeRaw(null,blocking,buf);
+            blocking.get(); // block till finished sending?
+        }
+        catch (InterruptedException e)
+        {
+            throw new IOException("Blocking write failed",e);
+        }
+        catch (ExecutionException e)
+        {
+            FutureCallback.rethrow(e);
+        }
+        finally
+        {
+            bufferPool.release(buf);
+        }
     }
 }

jetty-websocket/websocket-server/src/test/java/org/eclipse/jetty/websocket/server/examples/echo/EchoBroadcastPingSocket.java

@@ -30,7 +30,7 @@ public class EchoBroadcastPingSocket extends EchoBroadcastSocket
                     System.err.println("Ping " + pinger);
                     byte data[] = new byte[]
                     { (byte)1, (byte)2, (byte)3 };
-                    pinger.sendPing(data,0,3);
+                    pinger.sendPing(data);
                 }
             }
             catch (Exception e)