Java example source code file (OnThrowTest.java)

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

Learn more about this Java project at its project page.

Java - Java tags/keywords

bufferedinputstream, buffersize, exception, file, filewriter, object, onthrowtarget, onthrowtest, process, string, stringbuffer, test

The OnThrowTest.java Java example source code

/*
 * Copyright (c) 2005, 2006, 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       OnThrowTest.java
 *   @bug        6263814
 *   @summary    Test for -agentlib::[onthrow,launch]
 *   @author     Kelly O'Hair
 *
 *  @run compile -g OnThrowTest.java
 *  @run compile -g OnThrowTarget.java
 *  @run compile -g VMConnection.java
 *  @run main/othervm OnThrowTest
 */

import java.io.File;
import java.io.FileWriter;
import java.io.BufferedInputStream;
import java.io.IOException;

public class OnThrowTest extends Object {

    /* Full pathname for file to be touched or created by the launch */
    private String touchFile;

    OnThrowTest() throws Exception {
        /* Name of touch file */
        touchFile = System.getProperty("test.classes") +
                    File.separator + "OnThrowLaunchTouchFile";
        /* Make sure it's gone when we start */
        File f = new File(touchFile);
        f.delete();
        if ( f.exists() ) {
            throw new Exception("Test failed: Cannot remove old touch file: " +
                  touchFile);
        }
    }

    /* Used to see if touch file exists */
    private boolean touchFileExists() {
        File f = new File(touchFile);
        return f.exists();
    }

    /**
     * Run an arbitrary command
     *
     */
    public void run(String[] cmdStrings) throws Exception {
        StringBuffer stdoutBuffer = new StringBuffer();
        StringBuffer stderrBuffer = new StringBuffer();
        String CR = System.getProperty("line.separator");
        int subprocessStatus = 1;

        System.out.print(CR + "runCommand method about to execute: ");
        for (int iNdx = 0; iNdx < cmdStrings.length; iNdx++) {
            System.out.print(" ");
            System.out.print(cmdStrings[iNdx]);
        }
        System.out.println(CR);

        try {
            Process process = Runtime.getRuntime().
                exec(VMConnection.insertDebuggeeVMOptions(cmdStrings));
            int BUFFERSIZE = 4096;
            /*
             * Gather up the output of the subprocess using non-blocking
             * reads so we can get both the subprocess stdout and the
             * subprocess stderr without overfilling any buffers.
             */
            BufferedInputStream is =
                new BufferedInputStream(process.getInputStream());
            int isLen = 0;
            byte[] isBuf = new byte[BUFFERSIZE];

            BufferedInputStream es =
                new BufferedInputStream(process.getErrorStream());
            int esLen = 0;
            byte[] esBuf = new byte[BUFFERSIZE];

            do {
                isLen = is.read(isBuf);
                if (isLen > 0) {
                    stdoutBuffer.append(new String(isBuf, 0, isLen));
                }
                esLen = es.read(esBuf);
                if (esLen > 0) {
                    stderrBuffer.append(new String(esBuf, 0, esLen));
                }
            } while ((isLen > -1) || (esLen > -1));

            try {
                process.waitFor();
                subprocessStatus = process.exitValue();
                process = null;
            } catch(java.lang.InterruptedException e) {
                System.err.println("InterruptedException: " + e);
                throw new Exception("Test failed: process interrupted");
            }

        } catch(IOException ex) {
            System.err.println("IO error: " + ex);
            throw new Exception("Test failed: IO error running process");
        }

        System.out.println(CR + "--- Return code was: " +
                           CR + Integer.toString(subprocessStatus));
        System.out.println(CR + "--- Return stdout was: " +
                           CR + stdoutBuffer.toString());
        System.out.println(CR + "--- Return stderr was: " +
                           CR + stderrBuffer.toString());

    }

    public static void main(String[] args) throws Exception {

        OnThrowTest myTest = new OnThrowTest();

        String launch = System.getProperty("test.classes") +
                        File.separator + "OnThrowLaunch.sh";
        File f = new File(launch);
        f.delete();
        FileWriter fw = new FileWriter(f);
        fw.write("#!/bin/sh\n echo OK $* > " +
                 myTest.touchFile.replace('\\','/') + "\n exit 0\n");
        fw.flush();
        fw.close();
        if ( ! f.exists() ) {
            throw new Exception("Test failed: sh file not created: " + launch);
        }

        String javaExe = System.getProperty("java.home") +
                         File.separator + "bin" + File.separator + "java";
        String targetClass = "OnThrowTarget";
        String cmds [] = {javaExe,
                          "-agentlib:jdwp=transport=dt_socket," +
                          "onthrow=OnThrowException,server=y,suspend=n," +
                          "launch=" + "sh " + launch.replace('\\','/'),
                          targetClass};

        /* Run the target app, which will launch the launch script */
        myTest.run(cmds);
        if ( !myTest.touchFileExists() ) {
            throw new Exception("Test failed: touch file not found: " +
                  myTest.touchFile);
        }

        System.out.println("Test passed: launch create file");
    }

}