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	/*
	* Copyright (c) 2011, 2014, 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 sun.tools.jcmd;

	import java.io.InputStream;
	import java.io.IOException;
	import java.io.UnsupportedEncodingException;
	import java.util.List;
	import java.util.ArrayList;
	import java.util.Comparator;
	import java.net.URISyntaxException;

	import com.sun.tools.attach.AttachOperationFailedException;
	import com.sun.tools.attach.VirtualMachine;
	import com.sun.tools.attach.VirtualMachineDescriptor;
	import com.sun.tools.attach.AgentLoadException;
	import com.sun.tools.attach.AttachNotSupportedException;

	import sun.tools.attach.HotSpotVirtualMachine;
	import sun.tools.jstat.JStatLogger;
	import sun.jvmstat.monitor.Monitor;
	import sun.jvmstat.monitor.MonitoredHost;
	import sun.jvmstat.monitor.MonitoredVm;
	import sun.jvmstat.monitor.MonitoredVmUtil;
	import sun.jvmstat.monitor.MonitorException;
	import sun.jvmstat.monitor.VmIdentifier;

	public class JCmd {
	public static void main(String[] args) {
	Arguments arg = null;
	try {
	arg = new Arguments(args);
	} catch (IllegalArgumentException ex) {
	System.err.println("Error parsing arguments: " + ex.getMessage()
	+ "\n");
	Arguments.usage();
	System.exit(1);
	}

	if (arg.isShowUsage()) {
	Arguments.usage();
	System.exit(1);
	}

	if (arg.isListProcesses()) {
	List<VirtualMachineDescriptor> vmds = VirtualMachine.list();
	for (VirtualMachineDescriptor vmd : vmds) {
	System.out.println(vmd.id() + " " + vmd.displayName());
	}
	System.exit(0);
	}

	List<String> pids = new ArrayList<String>();
	if (arg.getPid() == 0) {
	// find all VMs
	List<VirtualMachineDescriptor> vmds = VirtualMachine.list();
	for (VirtualMachineDescriptor vmd : vmds) {
	if (!isJCmdProcess(vmd)) {
	pids.add(vmd.id());
	}
	}
	} else if (arg.getProcessSubstring() != null) {
	// use the partial class-name match
	List<VirtualMachineDescriptor> vmds = VirtualMachine.list();
	for (VirtualMachineDescriptor vmd : vmds) {
	if (isJCmdProcess(vmd)) {
	continue;
	}
	try {
	String mainClass = getMainClass(vmd);
	if (mainClass != null
	&& mainClass.indexOf(arg.getProcessSubstring()) != -1) {
	pids.add(vmd.id());
	}
	} catch (MonitorException\|URISyntaxException e) {
	if (e.getMessage() != null) {
	System.err.println(e.getMessage());
	} else {
	Throwable cause = e.getCause();
	if ((cause != null) && (cause.getMessage() != null)) {
	System.err.println(cause.getMessage());
	} else {
	e.printStackTrace();
	}
	}
	}
	}
	if (pids.isEmpty()) {
	System.err.println("Could not find any processes matching : '"
	+ arg.getProcessSubstring() + "'");
	System.exit(1);
	}
	} else if (arg.getPid() == -1) {
	System.err.println("Invalid pid specified");
	System.exit(1);
	} else {
	// Use the found pid
	pids.add(arg.getPid() + "");
	}

	boolean success = true;
	for (String pid : pids) {
	System.out.println(pid + ":");
	if (arg.isListCounters()) {
	listCounters(pid);
	} else {
	try {
	executeCommandForPid(pid, arg.getCommand());
	} catch(AttachOperationFailedException ex) {
	System.err.println(ex.getMessage());
	success = false;
	} catch(Exception ex) {
	ex.printStackTrace();
	success = false;
	}
	}
	}
	System.exit(success ? 0 : 1);
	}

	private static void executeCommandForPid(String pid, String command)
	throws AttachNotSupportedException, IOException,
	UnsupportedEncodingException {
	VirtualMachine vm = VirtualMachine.attach(pid);

	// Cast to HotSpotVirtualMachine as this is an
	// implementation specific method.
	HotSpotVirtualMachine hvm = (HotSpotVirtualMachine) vm;
	String lines[] = command.split("\\n");
	for (String line : lines) {
	if (line.trim().equals("stop")) {
	break;
	}
	try (InputStream in = hvm.executeJCmd(line);) {
	// read to EOF and just print output
	byte b[] = new byte[256];
	int n;
	boolean messagePrinted = false;
	do {
	n = in.read(b);
	if (n > 0) {
	String s = new String(b, 0, n, "UTF-8");
	System.out.print(s);
	messagePrinted = true;
	}
	} while (n > 0);
	if (!messagePrinted) {
	System.out.println("Command executed successfully");
	}
	}
	}
	vm.detach();
	}

	private static void listCounters(String pid) {
	// Code from JStat (can't call it directly since it does System.exit)
	VmIdentifier vmId = null;
	try {
	vmId = new VmIdentifier(pid);
	} catch (URISyntaxException e) {
	System.err.println("Malformed VM Identifier: " + pid);
	return;
	}
	try {
	MonitoredHost monitoredHost = MonitoredHost.getMonitoredHost(vmId);
	MonitoredVm monitoredVm = monitoredHost.getMonitoredVm(vmId, -1);
	JStatLogger logger = new JStatLogger(monitoredVm);
	logger.printSnapShot("\\w*", // all names
	new AscendingMonitorComparator(), // comparator
	false, // not verbose
	true, // show unsupported
	System.out);
	monitoredHost.detach(monitoredVm);
	} catch (MonitorException ex) {
	ex.printStackTrace();
	}
	}

	private static boolean isJCmdProcess(VirtualMachineDescriptor vmd) {
	try {
	String mainClass = getMainClass(vmd);
	return mainClass != null && mainClass.equals(JCmd.class.getName());
	} catch (URISyntaxException\|MonitorException ex) {
	return false;
	}
	}

	private static String getMainClass(VirtualMachineDescriptor vmd)
	throws URISyntaxException, MonitorException {
	try {
	String mainClass = null;
	VmIdentifier vmId = new VmIdentifier(vmd.id());
	MonitoredHost monitoredHost = MonitoredHost.getMonitoredHost(vmId);
	MonitoredVm monitoredVm = monitoredHost.getMonitoredVm(vmId, -1);
	mainClass = MonitoredVmUtil.mainClass(monitoredVm, true);
	monitoredHost.detach(monitoredVm);
	return mainClass;
	} catch(NullPointerException e) {
	// There is a potential race, where a running java app is being
	// queried, unfortunately the java app has shutdown after this
	// method is started but before getMonitoredVM is called.
	// If this is the case, then the /tmp/hsperfdata_xxx/pid file
	// will have disappeared and we will get a NullPointerException.
	// Handle this gracefully....
	return null;
	}
	}

	/**
	* Class to compare two Monitor objects by name in ascending order.
	* (from jstat)
	*/
	static class AscendingMonitorComparator implements Comparator<Monitor> {

	public int compare(Monitor m1, Monitor m2) {
	String name1 = m1.getName();
	String name2 = m2.getName();
	return name1.compareTo(name2);
	}
	}
	}

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