Add new onRetry callback method for AsyncHttpClient#435

Author: Stephane Landelle

src/main/java/com/ning/http/client/AsyncHandlerExtensions.java

@@ -19,7 +19,6 @@
  * 
  * More additional hooks might come, such as:
  * <ul>
- *   <li>onRetry()</li>
  *   <li>onConnected()</li>
  *   <li>onConnectionClosed()</li>
  *   <li>onBytesSent(long numberOfBytes)</li>
@@ -35,4 +34,9 @@ public interface AsyncHandlerExtensions {
      * Currently only supported by the Netty provider.
      */
     void onRequestSent();
+
+    /**
+     * Notify the callback every time a request is being retried.
+     */
+    void onRetry();
 }

src/main/java/com/ning/http/client/providers/netty/NettyAsyncHttpProvider.java

@@ -1297,6 +1297,9 @@ private FilterContext handleIoException(FilterContext fc, NettyResponseFuture<?>
     }
 
     private void replayRequest(final NettyResponseFuture<?> future, FilterContext fc, HttpResponse response, ChannelHandlerContext ctx) throws IOException {
+        if (future.getAsyncHandler() instanceof AsyncHandlerExtensions) {
+            AsyncHandlerExtensions.class.cast(future.getAsyncHandler()).onRetry();
+        }
         final Request newRequest = fc.getRequest();
         future.setAsyncHandler(fc.getAsyncHandler());
         future.setState(NettyResponseFuture.STATE.NEW);
@@ -1430,6 +1433,9 @@ protected boolean remotelyClosed(Channel channel, NettyResponseFuture<?> future)
         future.setState(NettyResponseFuture.STATE.RECONNECTED);
 
         log.debug("Trying to recover request {}\n", future.getNettyRequest());
+        if (future.getAsyncHandler() instanceof AsyncHandlerExtensions) {
+            AsyncHandlerExtensions.class.cast(future.getAsyncHandler()).onRetry();
+        }
 
         try {
             nextRequest(future.getRequest(), future);