@Override
            public void handle(IAsyncResult<IEngineResult> asyncResult) {
                if (asyncResult.isSuccess()) {
                    IEngineResult engineResult = asyncResult.getResult();
                    if (engineResult.isResponse()) {
                        try {
                            writeResponse(resp, engineResult.getApiResponse());
                            final ServletOutputStream outputStream = resp.getOutputStream();
                            engineResult.bodyHandler(new IAsyncHandler<IApimanBuffer>() {
                                @Override
                                public void handle(IApimanBuffer chunk) {
                                    try {
                                        if (chunk instanceof ByteBuffer) {
                                            byte [] buffer = (byte []) chunk.getNativeBuffer();
                                            outputStream.write(buffer, 0, chunk.length());
                                        } else {
                                            outputStream.write(chunk.getBytes());
                                        }
                                    } catch (IOException e) {
                                        // This will get caught by the API connector, which will abort the
                                        // connection to the back-end API.
                                        throw new RuntimeException(e);
                                    }
                                }
                            });
                            engineResult.endHandler(new IAsyncHandler<Void>() {
                                @Override
                                public void handle(Void result) {
                                    try {
                                        resp.flushBuffer();
                                    } catch (IOException e) {
                                        // This will get caught by the API connector, which will abort the
                                        // connection to the back-end API.
                                        throw new RuntimeException(e);
                                    } finally {
                                        latch.countDown();
                                    }
                                }
                            });
                        } catch (IOException e) {
                            // this would mean we couldn't get the output stream from the response, so we
                            // need to abort the engine result (which will let the back-end connection
                            // close down).
                            engineResult.abort(e);
                            latch.countDown();
                            throw new RuntimeException(e);
                        }
                    } else {
                        writeFailure(finalRequest, resp, engineResult.getPolicyFailure());
                        latch.countDown();
                    }
                } else {
                    writeError(finalRequest, resp, asyncResult.getError());
                    latch.countDown();
                }
            }
Generic handler for all types of http actions/verbs.
@param req
@param resp
@param action
gateway/platforms/servlet/src/main/java/io/apiman/gateway/platforms/servlet/GatewayServlet.java