/*
 * Copyright (c) 1999, 2013, 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.
 */

package com.sun.tools.jdi;

import com.sun.tools.jdi.*;
import com.sun.jdi.connect.*;
import com.sun.jdi.connect.spi.*;
import com.sun.jdi.*;

import java.util.Map;
import java.util.StringTokenizer;
import java.util.List;
import java.util.ArrayList;
import java.io.IOException;
import java.io.InterruptedIOException;

abstract class AbstractLauncher extends ConnectorImpl implements LaunchingConnector {

    abstract public VirtualMachine
        launch(Map<String,? extends Connector.Argument> arguments)
                                 throws IOException,
                                        IllegalConnectorArgumentsException,
                                        VMStartException;
    abstract public String name();
    abstract public String description();

    ThreadGroup grp;

    AbstractLauncher() {
        super();

        grp = Thread.currentThread().getThreadGroup();
        ThreadGroup parent = null;
        while ((parent = grp.getParent()) != null) {
            grp = parent;
        }
    }

    String[] tokenizeCommand(String command, char quote) {
        String quoteStr = String.valueOf(quote); // easier to deal with

        /*
         * Tokenize the command, respecting the given quote character.
         */
        StringTokenizer tokenizer = new StringTokenizer(command,
                                                        quote + " \t\r\n\f",
                                                        true);
        String quoted = null;
        String pending = null;
        List<String> tokenList = new ArrayList<String>();
        while (tokenizer.hasMoreTokens()) {
            String token = tokenizer.nextToken();
            if (quoted != null) {
                if (token.equals(quoteStr)) {
                    tokenList.add(quoted);
                    quoted = null;
                } else {
                    quoted += token;
                }
            } else if (pending != null) {
                if (token.equals(quoteStr)) {
                    quoted = pending;
                } else if ((token.length() == 1) &&
                           Character.isWhitespace(token.charAt(0))) {
                    tokenList.add(pending);
                } else {
                    throw new InternalException("Unexpected token: " + token);
                }
                pending = null;
            } else {
                if (token.equals(quoteStr)) {
                    quoted = "";
                } else if ((token.length() == 1) &&
                           Character.isWhitespace(token.charAt(0))) {
                    // continue
                } else {
                    pending = token;
                }
            }
        }

        /*
         * Add final token.
         */
        if (pending != null) {
            tokenList.add(pending);
        }

        /*
         * An unclosed quote at the end of the command. Do an
         * implicit end quote.
         */
        if (quoted != null) {
            tokenList.add(quoted);
        }

        String[] tokenArray = new String[tokenList.size()];
        for (int i = 0; i < tokenList.size(); i++) {
            tokenArray[i] = tokenList.get(i);
        }
        return tokenArray;
    }

    protected VirtualMachine launch(String[] commandArray, String address,
                                    TransportService.ListenKey listenKey,
                                    TransportService ts)
                                    throws IOException, VMStartException {
        Helper helper = new Helper(commandArray, address, listenKey, ts);
        helper.launchAndAccept();

        VirtualMachineManager manager =
            Bootstrap.virtualMachineManager();

        return manager.createVirtualMachine(helper.connection(),
                                            helper.process());
    }

    
This class simply provides a context for a single launch and accept. It provides instance fields that can be used by all threads involved. This stuff can't be in the Connector proper because the connector is a singleton and is not specific to any one launch.
/** * This class simply provides a context for a single launch and * accept. It provides instance fields that can be used by * all threads involved. This stuff can't be in the Connector proper * because the connector is a singleton and is not specific to any * one launch. */
private class Helper { private final String address; private TransportService.ListenKey listenKey; private TransportService ts; private final String[] commandArray; private Process process = null; private Connection connection = null; private IOException acceptException = null; private boolean exited = false; Helper(String[] commandArray, String address, TransportService.ListenKey listenKey, TransportService ts) { this.commandArray = commandArray; this.address = address; this.listenKey = listenKey; this.ts = ts; } String commandString() { String str = ""; for (int i = 0; i < commandArray.length; i++) { if (i > 0) { str += " "; } str += commandArray[i]; } return str; } synchronized void launchAndAccept() throws IOException, VMStartException { process = Runtime.getRuntime().exec(commandArray); Thread acceptingThread = acceptConnection(); Thread monitoringThread = monitorTarget(); try { while ((connection == null) && (acceptException == null) && !exited) { wait(); } if (exited) { throw new VMStartException( "VM initialization failed for: " + commandString(), process); } if (acceptException != null) { // Rethrow the exception in this thread throw acceptException; } } catch (InterruptedException e) { throw new InterruptedIOException("Interrupted during accept"); } finally { acceptingThread.interrupt(); monitoringThread.interrupt(); } } Process process() { return process; } Connection connection() { return connection; } synchronized void notifyOfExit() { exited = true; notify(); } synchronized void notifyOfConnection(Connection connection) { this.connection = connection; notify(); } synchronized void notifyOfAcceptException(IOException acceptException) { this.acceptException = acceptException; notify(); } Thread monitorTarget() { Thread thread = new Thread(grp, "launched target monitor") { public void run() { try { process.waitFor(); /* * Notify waiting thread of VM error termination */ notifyOfExit(); } catch (InterruptedException e) { // Connection has been established, stop monitoring } } }; thread.setDaemon(true); thread.start(); return thread; } Thread acceptConnection() { Thread thread = new Thread(grp, "connection acceptor") { public void run() { try { Connection connection = ts.accept(listenKey, 0, 0); /* * Notify waiting thread of connection */ notifyOfConnection(connection); } catch (InterruptedIOException e) { // VM terminated, stop accepting } catch (IOException e) { // Report any other exception to waiting thread notifyOfAcceptException(e); } } }; thread.setDaemon(true); thread.start(); return thread; } } }