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	/*
	* Copyright (c) 2004, 2011, 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.jvmstat.monitor;

	/**
	* Utility class proving concenience methods for extracting various
	* information from an MonitoredVm object.
	*
	* @author Brian Doherty
	* @since 1.5
	*/
	public class MonitoredVmUtil {

	/**
	* Private constructor - prevent instantiation.
	*/
	private MonitoredVmUtil() { }

	/**
	* Return the Java Virtual Machine Version.
	*
	* @param vm the target MonitoredVm
	* @return String - contains the version of the target JVM or the
	* the string "Unknown" if the version cannot be
	* determined.
	*/
	public static String vmVersion(MonitoredVm vm) throws MonitorException {
	StringMonitor ver =
	(StringMonitor)vm.findByName("java.property.java.vm.version");
	return (ver == null) ? "Unknown" : ver.stringValue();
	}

	/**
	* Return the command line for the target Java application.
	*
	* @param vm the target MonitoredVm
	* @return String - contains the command line of the target Java
	* application or the the string "Unknown" if the
	* command line cannot be determined.
	*/
	public static String commandLine(MonitoredVm vm) throws MonitorException {
	StringMonitor cmd = (StringMonitor)vm.findByName("sun.rt.javaCommand");
	return (cmd == null) ? "Unknown" : cmd.stringValue();
	}

	/**
	* Return the arguments to the main class for the target Java application.
	* Returns the arguments to the main class. If the arguments can't be
	* found, the string "Unknown" is returned.
	*
	* @param vm the target MonitoredVm
	* @return String - contains the arguments to the main class for the
	* target Java application or the the string "Unknown"
	* if the command line cannot be determined.
	*/
	public static String mainArgs(MonitoredVm vm) throws MonitorException {
	String commandLine = commandLine(vm);

	int firstSpace = commandLine.indexOf(' ');
	if (firstSpace > 0) {
	return commandLine.substring(firstSpace + 1);
	} else if (commandLine.compareTo("Unknown") == 0) {
	return commandLine;
	} else {
	return null;
	}
	}

	/**
	* Return the main class for the target Java application.
	* Returns the main class or the name of the jar file if the application
	* was started with the <em>-jar</em> option.
	*
	* @param vm the target MonitoredVm
	* @param fullPath include the full path to Jar file, where applicable
	* @return String - contains the main class of the target Java
	* application or the the string "Unknown" if the
	* command line cannot be determined.
	*/
	public static String mainClass(MonitoredVm vm, boolean fullPath)
	throws MonitorException {
	String commandLine = commandLine(vm);
	String arg0 = commandLine;

	int firstSpace = commandLine.indexOf(' ');
	if (firstSpace > 0) {
	arg0 = commandLine.substring(0, firstSpace);
	}
	if (!fullPath) {
	/*
	* can't use File.separator() here because the separator
	* for the target jvm may be different than the separator
	* for the monitoring jvm.
	*/
	int lastFileSeparator = arg0.lastIndexOf('/');
	if (lastFileSeparator > 0) {
	return arg0.substring(lastFileSeparator + 1);
	}

	lastFileSeparator = arg0.lastIndexOf('\\');
	if (lastFileSeparator > 0) {
	return arg0.substring(lastFileSeparator + 1);
	}

	int lastPackageSeparator = arg0.lastIndexOf('.');
	if (lastPackageSeparator > 0) {
	return arg0.substring(lastPackageSeparator + 1);
	}
	}
	return arg0;
	}

	/**
	* Return the JVM arguments for the target Java application.
	*
	* @param vm the target MonitoredVm
	* @return String - contains the arguments passed to the JVM for the
	* target Java application or the the string "Unknown"
	* if the command line cannot be determined.
	*/
	public static String jvmArgs(MonitoredVm vm) throws MonitorException {
	StringMonitor jvmArgs = (StringMonitor)vm.findByName("java.rt.vmArgs");
	return (jvmArgs == null) ? "Unknown" : jvmArgs.stringValue();
	}

	/**
	* Return the JVM flags for the target Java application.
	*
	* @param vm the target MonitoredVm
	* @return String - contains the flags passed to the JVM for the
	* target Java application or the the string "Unknown"
	* if the command line cannot be determined.
	*/
	public static String jvmFlags(MonitoredVm vm) throws MonitorException {
	StringMonitor jvmFlags =
	(StringMonitor)vm.findByName("java.rt.vmFlags");
	return (jvmFlags == null) ? "Unknown" : jvmFlags.stringValue();
	}

	// Index of the sun.rt.jvmCapabilities counter
	private static int IS_ATTACHABLE = 0;
	private static int IS_KERNEL_VM = 1;

	/**
	* Returns true if the VM supports attach-on-demand.
	*
	* @param vm the target MonitoredVm
	*/
	public static boolean isAttachable(MonitoredVm vm) throws MonitorException {
	StringMonitor jvmCapabilities =
	(StringMonitor)vm.findByName("sun.rt.jvmCapabilities");
	if (jvmCapabilities == null) {
	return false;
	} else {
	return jvmCapabilities.stringValue().charAt(IS_ATTACHABLE) == '1';
	}
	}

	}

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