/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * Oracle and Java are registered trademarks of Oracle and/or its affiliates.
 * Other names may be trademarks of their respective owners.
 *
 * 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
 * http://www.netbeans.org/cddl-gplv2.html
 * or nbbuild/licenses/CDDL-GPL-2-CP. 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
 * nbbuild/licenses/CDDL-GPL-2-CP.  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. If applicable, add the following below the
 * License Header, with the fields enclosed by brackets [] replaced by
 * your own identifying information:
 * "Portions Copyrighted [year] [name of copyright owner]"
 *
 * Contributor(s):
 * The Original Software is NetBeans. The Initial Developer of the Original
 * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
 * Microsystems, Inc. All Rights Reserved.
 *
 * 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 do not 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.
 */

package org.netbeans.lib.profiler.jps;

import org.netbeans.lib.profiler.utils.MiscUtils;
import sun.jvmstat.monitor.*;
import java.lang.management.ManagementFactory;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Set;


/**
 * This class is based on "jvmps" class from jvmps 2.0 written by Brian Doherty.
 * It provides functionality to identify all the JVMs currently running on the local machine.
 * Comments starting with //// are original comments from Brian.
 *
 * @author Tomas Hurka
 * @author Misha Dmitriev
 */
public class JpsProxy {
 
    //~ Methods ------------------------------------------------------------------------------------------------------------------

    /** Returns the array of records for all running VMs capable of dynamic attach (JDK 1.6 and newer)*/
    public static RunningVM[] getRunningVMs() {
        String hostname = null;
        List vret = new ArrayList();

        try {
            HostIdentifier hostId = new HostIdentifier(hostname);
            MonitoredHost monitoredHost = MonitoredHost.getMonitoredHost(hostId);
            String selfName = ManagementFactory.getRuntimeMXBean().getName();

            //// get the list active VMs on the specified host.
            Set jvms = monitoredHost.activeVms();

            if (jvms.isEmpty()) {
                return null;
            }

            for (Iterator j = jvms.iterator(); j.hasNext();) {
                int lvmid = ((Integer) j.next()).intValue();

                if (selfName.startsWith(lvmid + "@")) { // myself

                    continue;
                }

                VmIdentifier id = null;
                MonitoredVm vm = null;
                String uriString = "//" + lvmid + "?mode=r"; // NOI18N

                try {
                    id = new VmIdentifier(uriString);
                    vm = monitoredHost.getMonitoredVm(id, 0);
                } catch (URISyntaxException e) {
                    //// this error should not occur as we are creating our own VMIdentifiers above based on a validated HostIdentifier.
                    //// This would be an unexpected condition.
                    MiscUtils.printWarningMessage("in jvmps, detected malformed VM Identifier: " + uriString + "; ignored"); // NOI18N

                    continue;
                } catch (MonitorException e) {
                    System.out.println("Ex " + e.getMessage());
                    e.printStackTrace();

                    //// it's possible that from the time we acquired the list of available jvms that a jvm has terminated. Therefore, it is
                    //// best just to ignore this error.
                    continue;
                } catch (Exception e) {
                    //// certain types of errors, such as access acceptions, can be encountered when attaching to a jvm.
                    //// These are reported as exceptions, not as some subclass of security exception.

                    //// FIXME - we should probably have some provision for logging these types of errors, or possibly just print out the
                    //// the Java Virtual Machine lvmid in a finally clause: System.out.println(String.valueOf(lvmid));
                    MiscUtils.printWarningMessage("in jvmps, for VM = " + String.valueOf(lvmid) + " got exception: " + e); // NOI18N

                    continue;
                }

                if (!isAttachable(vm)) {
                    monitoredHost.detach(vm);

                    continue;
                }

                String cmdString = MonitoredVmUtil.commandLine(vm);
                String mainClass = MonitoredVmUtil.mainClass(vm, true);
                String mainArgs = MonitoredVmUtil.mainArgs(vm);
                String vmArgs = MonitoredVmUtil.jvmArgs(vm);
                String vmFlags = MonitoredVmUtil.jvmFlags(vm);

                monitoredHost.detach(vm);

                RunningVM rvm = new RunningVM(lvmid, vmFlags, vmArgs, mainClass, mainArgs);
                vret.add(rvm);
            }
        } catch (MonitorException e) {
            String report = "in jvmps, got MonitorException"; // NOI18N

            if (e.getMessage() != null) {
                report += (" with message + " + e.getMessage()); // NOI18N
            }

            MiscUtils.printWarningMessage(report);

            return null;
        } catch (URISyntaxException e) {
            MiscUtils.printWarningMessage("in jvmps, got malformed Host Identifier: " + hostname); // NOI18N

            return null;
        }

        return (RunningVM[]) vret.toArray(new RunningVM[0]);
    }

    private static boolean isAttachable(MonitoredVm vm) {
        try {
            return MonitoredVmUtil.isAttachable(vm);
        } catch (MonitorException ex) {
            ex.printStackTrace();
            return false;
        }
    }
}
