| /* |
| * Copyright (c) 2002, 2015, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* @test |
| * @bug 4669040 |
| * @summary Test DatagramChannel receive with empty buffer |
| * @author Mike McCloskey |
| */ |
| |
| import java.io.IOException; |
| import java.io.PrintStream; |
| import java.net.InetAddress; |
| import java.net.InetSocketAddress; |
| import java.net.SocketAddress; |
| import java.nio.ByteBuffer; |
| import java.nio.ByteOrder; |
| import java.nio.channels.ClosedByInterruptException; |
| import java.nio.channels.DatagramChannel; |
| |
| public class EmptyBuffer { |
| |
| private static final PrintStream log = System.err; |
| |
| public static void main(String[] args) throws Exception { |
| test(); |
| } |
| |
| private static void test() throws Exception { |
| DatagramChannel dc = DatagramChannel.open(); |
| InetAddress localHost = InetAddress.getLocalHost(); |
| dc.bind(new InetSocketAddress(localHost, 0)); |
| |
| Server server = new Server(dc.getLocalAddress()); |
| Thread serverThread = new Thread(server); |
| serverThread.start(); |
| |
| try { |
| InetSocketAddress isa = new InetSocketAddress(localHost, server.port()); |
| dc.connect(isa); |
| |
| ByteBuffer bb = ByteBuffer.allocateDirect(12); |
| bb.order(ByteOrder.BIG_ENDIAN); |
| bb.putInt(1).putLong(1); |
| bb.flip(); |
| |
| dc.write(bb); |
| bb.rewind(); |
| dc.write(bb); |
| bb.rewind(); |
| dc.write(bb); |
| |
| Thread.sleep(2000); |
| |
| serverThread.interrupt(); |
| server.throwException(); |
| } finally { |
| dc.close(); |
| } |
| } |
| |
| private static class Server implements Runnable { |
| private final DatagramChannel dc; |
| private final SocketAddress clientAddress; |
| private Exception e = null; |
| |
| Server(SocketAddress clientAddress) throws IOException { |
| this.dc = DatagramChannel.open().bind(new InetSocketAddress(0)); |
| this.clientAddress = clientAddress; |
| } |
| |
| int port() { |
| return dc.socket().getLocalPort(); |
| } |
| |
| void throwException() throws Exception { |
| if (e != null) |
| throw e; |
| } |
| |
| void showBuffer(String s, ByteBuffer bb) { |
| log.println(s); |
| bb.rewind(); |
| for (int i=0; i<bb.limit(); i++) { |
| byte element = bb.get(); |
| log.print(element); |
| } |
| log.println(); |
| } |
| |
| @Override |
| public void run() { |
| try { |
| ByteBuffer bb = ByteBuffer.allocateDirect(12); |
| bb.clear(); |
| // Only one clear. The buffer will be full after |
| // the first receive, but it should still block |
| // and receive and discard the next two |
| int numberReceived = 0; |
| while (!Thread.interrupted()) { |
| SocketAddress sa; |
| try { |
| sa = dc.receive(bb); |
| } catch (ClosedByInterruptException cbie) { |
| // Expected |
| log.println("Took expected exit"); |
| // Verify that enough packets were received |
| if (numberReceived != 3) |
| throw new RuntimeException("Failed: Too few datagrams"); |
| break; |
| } |
| if (sa != null) { |
| log.println("Client: " + sa); |
| // Check client address so as not to count stray packets |
| if (sa.equals(clientAddress)) { |
| showBuffer("RECV", bb); |
| numberReceived++; |
| } |
| if (numberReceived > 3) |
| throw new RuntimeException("Failed: Too many datagrams"); |
| sa = null; |
| } |
| } |
| } catch (Exception ex) { |
| e = ex; |
| } finally { |
| try { dc.close(); } catch (IOException ignore) { } |
| } |
| } |
| } |
| } |