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/*
* Copyright (c) 1999, 2018, 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 4176738
* @summary Make sure a deadlock situation
* would not occur
* @run main DeadlockTest
* @run main/othervm -Djava.net.preferIPv4Stack=true DeadlockTest
*/
import java.net.*;
import java.io.*;
public class DeadlockTest {
public static void main(String [] argv) throws Exception {
ServerSocket ss = new ServerSocket(0);
Socket clientSocket = new Socket();
try {
// Start the server thread
Thread s1 = new Thread(new ServerThread(ss));
s1.start();
// Start the client thread
ClientThread ct = new ClientThread(clientSocket, ss.getLocalPort());
Thread c1 = new Thread(ct);
c1.start();
// Wait for the client thread to finish
c1.join(20000);
// If timeout, we assume there is a deadlock
if (c1.isAlive() == true) {
// Close the socket to force the server thread
// terminate too
s1.stop();
throw new Exception("Takes too long. Dead lock");
}
} finally {
ss.close();
clientSocket.close();
}
}
}
class ServerThread implements Runnable {
private static boolean dbg = false;
ObjectInputStream in;
ObjectOutputStream out;
ServerSocket server;
Socket sock;
public ServerThread(ServerSocket serverSocket) throws Exception {
this.server = serverSocket;
}
public void ping(int cnt) {
Message.write(out, new PingMessage(cnt));
}
private int cnt = 1;
public void run() {
try {
if (Thread.currentThread().getName().startsWith("child") == false) {
sock = server.accept();
new Thread(this, "child").start();
out = new ObjectOutputStream(sock.getOutputStream());
out.flush();
if (dbg) System.out.println("*** ping0 ***");
ping(0);
if (dbg) System.out.println("*** ping1 ***");
ping(1);
if (dbg) System.out.println("*** ping2 ***");
ping(2);
if (dbg) System.out.println("*** ping3 ***");
ping(3);
if (dbg) System.out.println("*** ping4 ***");
ping(4);
if (dbg) System.out.println("*** end ***");
}
} catch (Throwable e) {
System.out.println(e);
// If anything goes wrong, just quit.
}
if (Thread.currentThread().getName().startsWith("child")) {
try {
in = new ObjectInputStream(sock.getInputStream());
while (true) {
if (dbg) System.out.println("read " + cnt);
Message msg = (Message) in.readObject();
if (dbg) System.out.println("read done " + cnt++);
switch (msg.code) {
case Message.PING: {
if (true) System.out.println("ping recv'ed");
} break;
}
}
} catch (Throwable e) {
// If anything goes wrong, just quit. }
}
}
}
}
class ClientThread implements Runnable {
ObjectInputStream in;
ObjectOutputStream out;
Socket sock;
public ClientThread(Socket sock, int serverPort) throws Exception {
try {
System.out.println("About to connect the client socket");
this.sock = sock;
this.sock.connect(new InetSocketAddress("localhost", serverPort));
System.out.println("connected");
out = new ObjectOutputStream(sock.getOutputStream());
out.flush();
} catch (Throwable e) {
System.out.println("client failed with: " + e);
e.printStackTrace();
throw new Exception("Unexpected exception");
}
}
private int cnt = 1;
public void run() {
try {
in = new ObjectInputStream(sock.getInputStream());
int count = 0;
while (true) {
System.out.println("read " + cnt);
Message msg = (Message) in.readObject();
System.out.println("read done " + cnt++);
switch (msg.code) {
case Message.PING: {
System.out.println("ping recv'ed");
count++;
} break;
}
if (count == 5) {
sock.close();
break;
}
}
} catch (IOException ioe) {
} catch (Throwable e) {
// If anything went wrong, just quit
}
}
}
class Message implements java.io.Serializable {
static final int UNKNOWN = 0;
static final int PING = 1;
protected int code;
public Message() { this.code = UNKNOWN; }
public Message(int code) { this.code = code; }
private static int cnt = 1;
public static void write(ObjectOutput out, Message msg) {
try {
System.out.println("write message " + cnt);
out.writeObject(msg);
System.out.println("flush message");
out.flush();
System.out.println("write message done " + cnt++);
} catch (IOException ioe) {
// Ignore the exception
System.out.println(ioe);
}
}
}
class PingMessage extends Message implements java.io.Serializable {
public PingMessage() {
code = Message.PING;
}
public PingMessage(int cnt)
{
code = Message.PING;
this.cnt = cnt;
data = new int[50000];
}
int cnt;
int[] data;
}
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