| // |
| // ======================================================================== |
| // Copyright (c) 1995-2017 Mort Bay Consulting Pty. Ltd. |
| // ------------------------------------------------------------------------ |
| // All rights reserved. This program and the accompanying materials |
| // are made available under the terms of the Eclipse Public License v1.0 |
| // and Apache License v2.0 which accompanies this distribution. |
| // |
| // The Eclipse Public License is available at |
| // http://www.eclipse.org/legal/epl-v10.html |
| // |
| // The Apache License v2.0 is available at |
| // http://www.opensource.org/licenses/apache2.0.php |
| // |
| // You may elect to redistribute this code under either of these licenses. |
| // ======================================================================== |
| // |
| |
| package org.eclipse.jetty.embedded; |
| |
| import java.io.IOException; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import javax.servlet.AsyncContext; |
| import javax.servlet.ReadListener; |
| import javax.servlet.ServletException; |
| import javax.servlet.ServletInputStream; |
| import javax.servlet.ServletOutputStream; |
| import javax.servlet.WriteListener; |
| import javax.servlet.http.HttpServlet; |
| import javax.servlet.http.HttpServletRequest; |
| import javax.servlet.http.HttpServletResponse; |
| |
| |
| public class AsyncEchoServlet extends HttpServlet |
| { |
| @Override |
| protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException |
| { |
| AsyncContext asyncContext = request.startAsync(request, response); |
| asyncContext.setTimeout(0); |
| Echoer echoer = new Echoer(asyncContext); |
| request.getInputStream().setReadListener(echoer); |
| response.getOutputStream().setWriteListener(echoer); |
| } |
| |
| private class Echoer implements ReadListener, WriteListener |
| { |
| private final byte[] buffer = new byte[4096]; |
| private final AsyncContext asyncContext; |
| private final ServletInputStream input; |
| private final ServletOutputStream output; |
| private final AtomicBoolean complete = new AtomicBoolean(false); |
| |
| private Echoer(AsyncContext asyncContext) throws IOException |
| { |
| this.asyncContext = asyncContext; |
| this.input = asyncContext.getRequest().getInputStream(); |
| this.output = asyncContext.getResponse().getOutputStream(); |
| } |
| |
| @Override |
| public void onDataAvailable() throws IOException |
| { |
| onWritePossible(); |
| } |
| |
| @Override |
| public void onAllDataRead() throws IOException |
| { |
| onWritePossible(); |
| } |
| |
| @Override |
| public void onWritePossible() throws IOException |
| { |
| // This method is called: |
| // 1) after first registering a WriteListener (ready for first write) |
| // 2) after first registering a ReadListener iff write is ready |
| // 3) when a previous write completes after an output.isReady() returns false |
| // 4) from an input callback |
| |
| // We should try to read, only if we are able to write! |
| while (output.isReady() && input.isReady()) |
| { |
| int read = input.read(buffer); |
| if (read<0) |
| { |
| if (complete.compareAndSet(false,true)) |
| asyncContext.complete(); |
| break; |
| } |
| else if (read>0) |
| { |
| output.write(buffer, 0, read); |
| } |
| } |
| } |
| |
| @Override |
| public void onError(Throwable failure) |
| { |
| failure.printStackTrace(); |
| asyncContext.complete(); |
| } |
| } |
| } |