Java example source code file (Main.java)

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Java - Java tags/keywords

aborting, boolean, file, guard, ioexception, main, never, querylistener, reachableexcludesimpl, runtimeexception, snapshot, string, thread

The Main.java Java example source code

/*
 * Copyright (c) 2005, 2008, 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.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * 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.
 */

/*
 * The Original Code is HAT. The Initial Developer of the
 * Original Code is Bill Foote, with contributions from others
 * at JavaSoft/Sun.
 */

package com.sun.tools.hat;

import java.io.IOException;
import java.io.File;

import com.sun.tools.hat.internal.model.Snapshot;
import com.sun.tools.hat.internal.model.ReachableExcludesImpl;
import com.sun.tools.hat.internal.server.QueryListener;

/**
 *
 * @author      Bill Foote
 */


public class Main {

    private static String VERSION_STRING = "jhat version 2.0";

    private static void usage(String message) {
        if ( message != null ) {
            System.err.println("ERROR: " + message);
        }
        System.err.println("Usage:  jhat [-stack <bool>] [-refs ] [-port ] [-baseline ] [-debug ] [-version] [-h|-help] ");
        System.err.println();
        System.err.println("\t-J<flag>          Pass  directly to the runtime system. For");
        System.err.println("\t\t\t  example, -J-mx512m to use a maximum heap size of 512MB");
        System.err.println("\t-stack false:     Turn off tracking object allocation call stack.");
        System.err.println("\t-refs false:      Turn off tracking of references to objects");
        System.err.println("\t-port <port>:     Set the port for the HTTP server.  Defaults to 7000");
        System.err.println("\t-exclude <file>:  Specify a file that lists data members that should");
        System.err.println("\t\t\t  be excluded from the reachableFrom query.");
        System.err.println("\t-baseline <file>: Specify a baseline object dump.  Objects in");
        System.err.println("\t\t\t  both heap dumps with the same ID and same class will");
        System.err.println("\t\t\t  be marked as not being \"new\".");
        System.err.println("\t-debug <int>:     Set debug level.");
        System.err.println("\t\t\t    0:  No debug output");
        System.err.println("\t\t\t    1:  Debug hprof file parsing");
        System.err.println("\t\t\t    2:  Debug hprof file parsing, no server");
        System.err.println("\t-version          Report version number");
        System.err.println("\t-h|-help          Print this help and exit");
        System.err.println("\t<file>            The file to read");
        System.err.println();
        System.err.println("For a dump file that contains multiple heap dumps,");
        System.err.println("you may specify which dump in the file");
        System.err.println("by appending \"#<number>\" to the file name, i.e. \"foo.hprof#3\".");
        System.err.println();
        System.err.println("All boolean options default to \"true\"");
        System.exit(1);
    }

    //
    // Convert s to a boolean.  If it's invalid, abort the program.
    //
    private static boolean booleanValue(String s) {
        if ("true".equalsIgnoreCase(s)) {
            return true;
        } else if ("false".equalsIgnoreCase(s)) {
            return false;
        } else {
            usage("Boolean value must be true or false");
            return false;       // Never happens
        }
    }

    public static void main(String[] args) {
        if (args.length < 1) {
            usage("No arguments supplied");
        }

        boolean parseonly = false;
        int portNumber = 7000;
        boolean callStack = true;
        boolean calculateRefs = true;
        String baselineDump = null;
        String excludeFileName = null;
        int debugLevel = 0;
        for (int i = 0; ; i += 2) {
            if (i > (args.length - 1)) {
                usage("Option parsing error");
            }
            if ("-version".equals(args[i])) {
                System.out.print(VERSION_STRING);
                System.out.println(" (java version " + System.getProperty("java.version") + ")");
                System.exit(0);
            }

            if ("-h".equals(args[i]) || "-help".equals(args[i])) {
                usage(null);
            }

            if (i == (args.length - 1)) {
                break;
            }
            String key = args[i];
            String value = args[i+1];
            if ("-stack".equals(key)) {
                callStack = booleanValue(value);
            } else if ("-refs".equals(key)) {
                calculateRefs = booleanValue(value);
            } else if ("-port".equals(key)) {
                portNumber = Integer.parseInt(value, 10);
            } else if ("-exclude".equals(key)) {
                excludeFileName = value;
            } else if ("-baseline".equals(key)) {
                baselineDump = value;
            } else if ("-debug".equals(key)) {
                debugLevel = Integer.parseInt(value, 10);
            } else if ("-parseonly".equals(key)) {
                // Undocumented option. To be used for testing purpose only
                parseonly = booleanValue(value);
            }
        }
        String fileName = args[args.length - 1];
        Snapshot model = null;
        File excludeFile = null;
        if (excludeFileName != null) {
            excludeFile = new File(excludeFileName);
            if (!excludeFile.exists()) {
                System.out.println("Exclude file " + excludeFile
                                    + " does not exist.  Aborting.");
                System.exit(1);
            }
        }

        System.out.println("Reading from " + fileName + "...");
        try {
            model = com.sun.tools.hat.internal.parser.Reader.readFile(fileName, callStack, debugLevel);
        } catch (IOException ex) {
            ex.printStackTrace();
            System.exit(1);
        } catch (RuntimeException ex) {
            ex.printStackTrace();
            System.exit(1);
        }
        System.out.println("Snapshot read, resolving...");
        model.resolve(calculateRefs);
        System.out.println("Snapshot resolved.");

        if (excludeFile != null) {
            model.setReachableExcludes(new ReachableExcludesImpl(excludeFile));
        }

        if (baselineDump != null) {
            System.out.println("Reading baseline snapshot...");
            Snapshot baseline = null;
            try {
                baseline = com.sun.tools.hat.internal.parser.Reader.readFile(baselineDump, false,
                                                      debugLevel);
            } catch (IOException ex) {
                ex.printStackTrace();
                System.exit(1);
            } catch (RuntimeException ex) {
                ex.printStackTrace();
                System.exit(1);
            }
            baseline.resolve(false);
            System.out.println("Discovering new objects...");
            model.markNewRelativeTo(baseline);
            baseline = null;    // Guard against conservative GC
        }
        if ( debugLevel == 2 ) {
            System.out.println("No server, -debug 2 was used.");
            System.exit(0);
        }

        if (parseonly) {
            // do not start web server.
            System.out.println("-parseonly is true, exiting..");
            System.exit(0);
        }

        QueryListener listener = new QueryListener(portNumber);
        listener.setModel(model);
        Thread t = new Thread(listener, "Query Listener");
        t.setPriority(Thread.NORM_PRIORITY+1);
        t.start();
        System.out.println("Started HTTP server on port " + portNumber);
        System.out.println("Server is ready.");
    }
}