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Glassfish example source code file (ProcessManager.java)

This example Glassfish source code file (ProcessManager.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Java - Glassfish tags/keywords

bufferedreader, exception, interruptedexception, io, processmanager, processmanagerexception, processmanagerexception, readerthread, string, string, stringbuffer, stringbuffer, thread, thread, timeoutthread, util

The Glassfish ProcessManager.java source code

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 2009-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
 *
 * Contributor(s):
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

/*
 * ProcessManager.java
 * Use this class for painless process spawning.
 * This class was specifically written to be compatable with 1.4
 * @since JDK 1.4
 * @author bnevins
 * Created on October 28, 2005, 10:08 PM
 */
package com.sun.enterprise.universal.process;

import java.io.*;
import java.util.*;

/**
 *
 */
public class ProcessManager {

    public ProcessManager(String... cmds) {
        cmdline = cmds;
    }

    ////////////////////////////////////////////////////////////////////////////
    public ProcessManager(List<String> Cmdline) {
        cmdline = new String[Cmdline.size()];
        cmdline = (String[]) Cmdline.toArray(cmdline);
    }

    ////////////////////////////////////////////////////////////////////////////
    public final void setTimeoutMsec(int num) {
        if (num > 0) {
            timeout = num;
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    public final void setStdinLines(List<String> list) {
        if (list != null && list.size() > 0) {
            stdinLines = new String[list.size()];
            stdinLines = (String[]) list.toArray(stdinLines);
        }
    }

    public final void waitForReaderThreads(boolean b) {
        waitForReaderThreads = b;
    }
    
    ////////////////////////////////////////////////////////////////////////////
    /** Should the output of the process be echoed to stdout?
     *
     * @param newEcho
     */
    public final void setEcho(boolean newEcho) {
        echo = newEcho;
    }

    ////////////////////////////////////////////////////////////////////////////
    public final int execute() throws ProcessManagerException {
        try {
            sb_out = new StringBuffer();
            sb_err = new StringBuffer();

            Runtime rt = Runtime.getRuntime();
            process = rt.exec(cmdline);
            readStream("stderr", process.getErrorStream(), sb_err);
            readStream("stdout", process.getInputStream(), sb_out);
            writeStdin();
            await();

            try {
                exit = process.exitValue();
                wasError = false;
            }
            catch (IllegalThreadStateException tse) {
                // this means that the process is still running...
                process.destroy();
                throw new ProcessManagerTimeoutException(tse);
            }
        }
        catch (ProcessManagerException pme) {
            throw pme;
        }
        catch (Exception e) {
            if (process != null) {
                process.destroy();
            }

            throw new ProcessManagerException(e);
        }

        return exit;
    }

    ////////////////////////////////////////////////////////////////////////////
    public final String getStdout() {
        return sb_out.toString();
    }

    ////////////////////////////////////////////////////////////////////////////
    public final String getStderr() {
        return sb_err.toString();
    }

    ////////////////////////////////////////////////////////////////////////////
    public final int getExitValue() {
        return exit;
    }

    ////////////////////////////////////////////////////////////////////////////
    public String toString() {
        return Arrays.toString(cmdline);
    }

    ////////////////////////////////////////////////////////////////////////////
    private void writeStdin() throws ProcessManagerException {
        if (stdinLines == null || stdinLines.length <= 0) {
            return;
        }

        PrintWriter pipe = null;

        try {
            pipe = new PrintWriter(new BufferedWriter(new OutputStreamWriter(process.getOutputStream())));

            for (int i = 0; i < stdinLines.length; i++) {
                debug("InputLine ->" + stdinLines[i] + "<-");
                pipe.println(stdinLines[i]);
            }
            pipe.flush();
        }
        catch (Exception e) {
            throw new ProcessManagerException(e);
        }
        finally {
            try {
                pipe.close();
            }
            catch (Throwable t) {
            }
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    private void readStream(String name, InputStream stream, StringBuffer sb) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
        Thread thread = new Thread(new ReaderThread(reader, sb, echo), name);
        threads.add(thread);
        thread.start();
    }

    ////////////////////////////////////////////////////////////////////////////
    private void await() throws InterruptedException {
        if (timeout <= 0) {
            waitForever();
        }
        else {
            waitAwhile();
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    private void waitForever() throws InterruptedException {
        process.waitFor();

        if (waitForReaderThreads)
        {
            // wait for stdin and stderr to finish up
            for (Thread t : threads) {
                t.join();
            }
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    private void waitAwhile() throws InterruptedException {
        {
            Thread processWaiter = new Thread(new TimeoutThread(process));
            processWaiter.start();
            processWaiter.join(timeout);
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    private static void debug(String s) {
        if (debugOn) {
            System.out.println(s);
        }
    }

    ////////////////////////////////////////////////////////////////////////////
    public static void main(String[] args) {
        try {
            if (args.length <= 0) {
                System.out.println("Usage: ProcessManager cmd arg1 arg2 ... argn");
                System.exit(1);
            }

            List<String> cmds = new ArrayList();

            for (int i = 0; i < args.length; i++) {
                cmds.add(args[i]);
            }

            ProcessManager pm = new ProcessManager(cmds);
            pm.execute();

            System.out.println("*********** STDOUT ***********\n" + pm.getStdout());
            System.out.println("*********** STDERR ***********\n" + pm.getStderr());
            System.out.println("*********** EXIT VALUE: " + pm.getExitValue());
        }
        catch (ProcessManagerException pme) {
            pme.printStackTrace();
        }
    }
    ////////////////////////////////////////////////////////////////////////////
    private String[] cmdline;
    private StringBuffer sb_out;
    private StringBuffer sb_err;
    private int exit = -1;
    private int timeout;
    private Process process;
    private boolean wasError = true;
    private boolean echo = true;
    private static final boolean debugOn = false;
    private String[] stdinLines;
    private List<Thread> threads = new ArrayList(2);
    private boolean waitForReaderThreads = true;
    ////////////////////////////////////////////////////////////////////////////

    static class ReaderThread implements Runnable {

        ReaderThread(BufferedReader Reader, StringBuffer SB, boolean echo) {
            reader = Reader;
            sb = SB;
            this.echo = echo;
        }

        public void run() {
            try {
                for (String line = reader.readLine(); line != null; line = reader.readLine()) {
                    sb.append(line).append('\n');

                    if (echo)
                        System.out.println(line);
                }
            }
            catch (Exception e) {
            }
            ProcessManager.debug("ReaderThread exiting...");
        }
        private BufferedReader reader;
        private StringBuffer sb;
        private boolean echo;
    }

    static class TimeoutThread implements Runnable {

        TimeoutThread(Process p) {
            process = p;
        }

        public void run() {
            try {
                process.waitFor();
            }
            catch (Exception e) {
            }
            ProcessManager.debug("TimeoutThread exiting...");
        }
        private Process process;
    }
}

Other Glassfish examples (source code examples)

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