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	/*
	* Copyright (c) 1995, 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 java.lang;

	import java.io.*;
	import java.util.StringTokenizer;
	import sun.reflect.CallerSensitive;
	import sun.reflect.Reflection;

	/**
	* Every Java application has a single instance of class
	* <code>Runtime</code> that allows the application to interface with
	* the environment in which the application is running. The current
	* runtime can be obtained from the <code>getRuntime</code> method.
	* <p>
	* An application cannot create its own instance of this class.
	*
	* @author unascribed
	* @see java.lang.Runtime#getRuntime()
	* @since JDK1.0
	*/

	public class Runtime {
	private static Runtime currentRuntime = new Runtime();

	/**
	* Returns the runtime object associated with the current Java application.
	* Most of the methods of class <code>Runtime</code> are instance
	* methods and must be invoked with respect to the current runtime object.
	*
	* @return the <code>Runtime</code> object associated with the current
	* Java application.
	*/
	public static Runtime getRuntime() {
	return currentRuntime;
	}

	/** Don't let anyone else instantiate this class */
	private Runtime() {}

	/**
	* Terminates the currently running Java virtual machine by initiating its
	* shutdown sequence. This method never returns normally. The argument
	* serves as a status code; by convention, a nonzero status code indicates
	* abnormal termination.
	*
	* <p> The virtual machine's shutdown sequence consists of two phases. In
	* the first phase all registered {@link #addShutdownHook shutdown hooks},
	* if any, are started in some unspecified order and allowed to run
	* concurrently until they finish. In the second phase all uninvoked
	* finalizers are run if {@link #runFinalizersOnExit finalization-on-exit}
	* has been enabled. Once this is done the virtual machine {@link #halt
	* halts}.
	*
	* <p> If this method is invoked after the virtual machine has begun its
	* shutdown sequence then if shutdown hooks are being run this method will
	* block indefinitely. If shutdown hooks have already been run and on-exit
	* finalization has been enabled then this method halts the virtual machine
	* with the given status code if the status is nonzero; otherwise, it
	* blocks indefinitely.
	*
	* <p> The <tt>{@link System#exit(int) System.exit}</tt> method is the
	* conventional and convenient means of invoking this method. <p>
	*
	* @param status
	* Termination status. By convention, a nonzero status code
	* indicates abnormal termination.
	*
	* @throws SecurityException
	* If a security manager is present and its <tt>{@link
	* SecurityManager#checkExit checkExit}</tt> method does not permit
	* exiting with the specified status
	*
	* @see java.lang.SecurityException
	* @see java.lang.SecurityManager#checkExit(int)
	* @see #addShutdownHook
	* @see #removeShutdownHook
	* @see #runFinalizersOnExit
	* @see #halt(int)
	*/
	public void exit(int status) {
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	security.checkExit(status);
	}
	Shutdown.exit(status);
	}

	/**
	* Registers a new virtual-machine shutdown hook.
	*
	* <p> The Java virtual machine <i>shuts down</i> in response to two kinds
	* of events:
	*
	* <ul>
	*
	* <li> The program <i>exits</i> normally, when the last non-daemon
	* thread exits or when the <tt>{@link #exit exit}</tt> (equivalently,
	* {@link System#exit(int) System.exit}) method is invoked, or
	*
	* <li> The virtual machine is <i>terminated</i> in response to a
	* user interrupt, such as typing <tt>^C</tt>, or a system-wide event,
	* such as user logoff or system shutdown.
	*
	* </ul>
	*
	* <p> A <i>shutdown hook</i> is simply an initialized but unstarted
	* thread. When the virtual machine begins its shutdown sequence it will
	* start all registered shutdown hooks in some unspecified order and let
	* them run concurrently. When all the hooks have finished it will then
	* run all uninvoked finalizers if finalization-on-exit has been enabled.
	* Finally, the virtual machine will halt. Note that daemon threads will
	* continue to run during the shutdown sequence, as will non-daemon threads
	* if shutdown was initiated by invoking the <tt>{@link #exit exit}</tt>
	* method.
	*
	* <p> Once the shutdown sequence has begun it can be stopped only by
	* invoking the <tt>{@link #halt halt}</tt> method, which forcibly
	* terminates the virtual machine.
	*
	* <p> Once the shutdown sequence has begun it is impossible to register a
	* new shutdown hook or de-register a previously-registered hook.
	* Attempting either of these operations will cause an
	* <tt>{@link IllegalStateException}</tt> to be thrown.
	*
	* <p> Shutdown hooks run at a delicate time in the life cycle of a virtual
	* machine and should therefore be coded defensively. They should, in
	* particular, be written to be thread-safe and to avoid deadlocks insofar
	* as possible. They should also not rely blindly upon services that may
	* have registered their own shutdown hooks and therefore may themselves in
	* the process of shutting down. Attempts to use other thread-based
	* services such as the AWT event-dispatch thread, for example, may lead to
	* deadlocks.
	*
	* <p> Shutdown hooks should also finish their work quickly. When a
	* program invokes <tt>{@link #exit exit}</tt> the expectation is
	* that the virtual machine will promptly shut down and exit. When the
	* virtual machine is terminated due to user logoff or system shutdown the
	* underlying operating system may only allow a fixed amount of time in
	* which to shut down and exit. It is therefore inadvisable to attempt any
	* user interaction or to perform a long-running computation in a shutdown
	* hook.
	*
	* <p> Uncaught exceptions are handled in shutdown hooks just as in any
	* other thread, by invoking the <tt>{@link ThreadGroup#uncaughtException
	* uncaughtException}</tt> method of the thread's <tt>{@link
	* ThreadGroup}</tt> object. The default implementation of this method
	* prints the exception's stack trace to <tt>{@link System#err}</tt> and
	* terminates the thread; it does not cause the virtual machine to exit or
	* halt.
	*
	* <p> In rare circumstances the virtual machine may <i>abort</i>, that is,
	* stop running without shutting down cleanly. This occurs when the
	* virtual machine is terminated externally, for example with the
	* <tt>SIGKILL</tt> signal on Unix or the <tt>TerminateProcess</tt> call on
	* Microsoft Windows. The virtual machine may also abort if a native
	* method goes awry by, for example, corrupting internal data structures or
	* attempting to access nonexistent memory. If the virtual machine aborts
	* then no guarantee can be made about whether or not any shutdown hooks
	* will be run. <p>
	*
	* @param hook
	* An initialized but unstarted <tt>{@link Thread}</tt> object
	*
	* @throws IllegalArgumentException
	* If the specified hook has already been registered,
	* or if it can be determined that the hook is already running or
	* has already been run
	*
	* @throws IllegalStateException
	* If the virtual machine is already in the process
	* of shutting down
	*
	* @throws SecurityException
	* If a security manager is present and it denies
	* <tt>{@link RuntimePermission}("shutdownHooks")</tt>
	*
	* @see #removeShutdownHook
	* @see #halt(int)
	* @see #exit(int)
	* @since 1.3
	*/
	public void addShutdownHook(Thread hook) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	sm.checkPermission(new RuntimePermission("shutdownHooks"));
	}
	ApplicationShutdownHooks.add(hook);
	}

	/**
	* De-registers a previously-registered virtual-machine shutdown hook. <p>
	*
	* @param hook the hook to remove
	* @return <tt>true</tt> if the specified hook had previously been
	* registered and was successfully de-registered, <tt>false</tt>
	* otherwise.
	*
	* @throws IllegalStateException
	* If the virtual machine is already in the process of shutting
	* down
	*
	* @throws SecurityException
	* If a security manager is present and it denies
	* <tt>{@link RuntimePermission}("shutdownHooks")</tt>
	*
	* @see #addShutdownHook
	* @see #exit(int)
	* @since 1.3
	*/
	public boolean removeShutdownHook(Thread hook) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	sm.checkPermission(new RuntimePermission("shutdownHooks"));
	}
	return ApplicationShutdownHooks.remove(hook);
	}

	/**
	* Forcibly terminates the currently running Java virtual machine. This
	* method never returns normally.
	*
	* <p> This method should be used with extreme caution. Unlike the
	* <tt>{@link #exit exit}</tt> method, this method does not cause shutdown
	* hooks to be started and does not run uninvoked finalizers if
	* finalization-on-exit has been enabled. If the shutdown sequence has
	* already been initiated then this method does not wait for any running
	* shutdown hooks or finalizers to finish their work. <p>
	*
	* @param status
	* Termination status. By convention, a nonzero status code
	* indicates abnormal termination. If the <tt>{@link Runtime#exit
	* exit}</tt> (equivalently, <tt>{@link System#exit(int)
	* System.exit}</tt>) method has already been invoked then this
	* status code will override the status code passed to that method.
	*
	* @throws SecurityException
	* If a security manager is present and its <tt>{@link
	* SecurityManager#checkExit checkExit}</tt> method does not permit
	* an exit with the specified status
	*
	* @see #exit
	* @see #addShutdownHook
	* @see #removeShutdownHook
	* @since 1.3
	*/
	public void halt(int status) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	sm.checkExit(status);
	}
	Shutdown.beforeHalt();
	Shutdown.halt(status);
	}

	/**
	* Enable or disable finalization on exit; doing so specifies that the
	* finalizers of all objects that have finalizers that have not yet been
	* automatically invoked are to be run before the Java runtime exits.
	* By default, finalization on exit is disabled.
	*
	* <p>If there is a security manager,
	* its <code>checkExit</code> method is first called
	* with 0 as its argument to ensure the exit is allowed.
	* This could result in a SecurityException.
	*
	* @param value true to enable finalization on exit, false to disable
	* @deprecated This method is inherently unsafe. It may result in
	* finalizers being called on live objects while other threads are
	* concurrently manipulating those objects, resulting in erratic
	* behavior or deadlock.
	*
	* @throws SecurityException
	* if a security manager exists and its <code>checkExit</code>
	* method doesn't allow the exit.
	*
	* @see java.lang.Runtime#exit(int)
	* @see java.lang.Runtime#gc()
	* @see java.lang.SecurityManager#checkExit(int)
	* @since JDK1.1
	*/
	@Deprecated
	public static void runFinalizersOnExit(boolean value) {
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	try {
	security.checkExit(0);
	} catch (SecurityException e) {
	throw new SecurityException("runFinalizersOnExit");
	}
	}
	Shutdown.setRunFinalizersOnExit(value);
	}

	/**
	* Executes the specified string command in a separate process.
	*
	* <p>This is a convenience method. An invocation of the form
	* <tt>exec(command)</tt>
	* behaves in exactly the same way as the invocation
	* <tt>{@link #exec(String, String[], File) exec}(command, null, null)</tt>.
	*
	* @param command a specified system command.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>command</code> is <code>null</code>
	*
	* @throws IllegalArgumentException
	* If <code>command</code> is empty
	*
	* @see #exec(String[], String[], File)
	* @see ProcessBuilder
	*/
	public Process exec(String command) throws IOException {
	return exec(command, null, null);
	}

	/**
	* Executes the specified string command in a separate process with the
	* specified environment.
	*
	* <p>This is a convenience method. An invocation of the form
	* <tt>exec(command, envp)</tt>
	* behaves in exactly the same way as the invocation
	* <tt>{@link #exec(String, String[], File) exec}(command, envp, null)</tt>.
	*
	* @param command a specified system command.
	*
	* @param envp array of strings, each element of which
	* has environment variable settings in the format
	* <i>name</i>=<i>value</i>, or
	* <tt>null</tt> if the subprocess should inherit
	* the environment of the current process.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>command</code> is <code>null</code>,
	* or one of the elements of <code>envp</code> is <code>null</code>
	*
	* @throws IllegalArgumentException
	* If <code>command</code> is empty
	*
	* @see #exec(String[], String[], File)
	* @see ProcessBuilder
	*/
	public Process exec(String command, String[] envp) throws IOException {
	return exec(command, envp, null);
	}

	/**
	* Executes the specified string command in a separate process with the
	* specified environment and working directory.
	*
	* <p>This is a convenience method. An invocation of the form
	* <tt>exec(command, envp, dir)</tt>
	* behaves in exactly the same way as the invocation
	* <tt>{@link #exec(String[], String[], File) exec}(cmdarray, envp, dir)</tt>,
	* where <code>cmdarray</code> is an array of all the tokens in
	* <code>command</code>.
	*
	* <p>More precisely, the <code>command</code> string is broken
	* into tokens using a {@link StringTokenizer} created by the call
	* <code>new {@link StringTokenizer}(command)</code> with no
	* further modification of the character categories. The tokens
	* produced by the tokenizer are then placed in the new string
	* array <code>cmdarray</code>, in the same order.
	*
	* @param command a specified system command.
	*
	* @param envp array of strings, each element of which
	* has environment variable settings in the format
	* <i>name</i>=<i>value</i>, or
	* <tt>null</tt> if the subprocess should inherit
	* the environment of the current process.
	*
	* @param dir the working directory of the subprocess, or
	* <tt>null</tt> if the subprocess should inherit
	* the working directory of the current process.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>command</code> is <code>null</code>,
	* or one of the elements of <code>envp</code> is <code>null</code>
	*
	* @throws IllegalArgumentException
	* If <code>command</code> is empty
	*
	* @see ProcessBuilder
	* @since 1.3
	*/
	public Process exec(String command, String[] envp, File dir)
	throws IOException {
	if (command.length() == 0)
	throw new IllegalArgumentException("Empty command");

	StringTokenizer st = new StringTokenizer(command);
	String[] cmdarray = new String[st.countTokens()];
	for (int i = 0; st.hasMoreTokens(); i++)
	cmdarray[i] = st.nextToken();
	return exec(cmdarray, envp, dir);
	}

	/**
	* Executes the specified command and arguments in a separate process.
	*
	* <p>This is a convenience method. An invocation of the form
	* <tt>exec(cmdarray)</tt>
	* behaves in exactly the same way as the invocation
	* <tt>{@link #exec(String[], String[], File) exec}(cmdarray, null, null)</tt>.
	*
	* @param cmdarray array containing the command to call and
	* its arguments.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>cmdarray</code> is <code>null</code>,
	* or one of the elements of <code>cmdarray</code> is <code>null</code>
	*
	* @throws IndexOutOfBoundsException
	* If <code>cmdarray</code> is an empty array
	* (has length <code>0</code>)
	*
	* @see ProcessBuilder
	*/
	public Process exec(String cmdarray[]) throws IOException {
	return exec(cmdarray, null, null);
	}

	/**
	* Executes the specified command and arguments in a separate process
	* with the specified environment.
	*
	* <p>This is a convenience method. An invocation of the form
	* <tt>exec(cmdarray, envp)</tt>
	* behaves in exactly the same way as the invocation
	* <tt>{@link #exec(String[], String[], File) exec}(cmdarray, envp, null)</tt>.
	*
	* @param cmdarray array containing the command to call and
	* its arguments.
	*
	* @param envp array of strings, each element of which
	* has environment variable settings in the format
	* <i>name</i>=<i>value</i>, or
	* <tt>null</tt> if the subprocess should inherit
	* the environment of the current process.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>cmdarray</code> is <code>null</code>,
	* or one of the elements of <code>cmdarray</code> is <code>null</code>,
	* or one of the elements of <code>envp</code> is <code>null</code>
	*
	* @throws IndexOutOfBoundsException
	* If <code>cmdarray</code> is an empty array
	* (has length <code>0</code>)
	*
	* @see ProcessBuilder
	*/
	public Process exec(String[] cmdarray, String[] envp) throws IOException {
	return exec(cmdarray, envp, null);
	}


	/**
	* Executes the specified command and arguments in a separate process with
	* the specified environment and working directory.
	*
	* <p>Given an array of strings <code>cmdarray</code>, representing the
	* tokens of a command line, and an array of strings <code>envp</code>,
	* representing "environment" variable settings, this method creates
	* a new process in which to execute the specified command.
	*
	* <p>This method checks that <code>cmdarray</code> is a valid operating
	* system command. Which commands are valid is system-dependent,
	* but at the very least the command must be a non-empty list of
	* non-null strings.
	*
	* <p>If <tt>envp</tt> is <tt>null</tt>, the subprocess inherits the
	* environment settings of the current process.
	*
	* <p>A minimal set of system dependent environment variables may
	* be required to start a process on some operating systems.
	* As a result, the subprocess may inherit additional environment variable
	* settings beyond those in the specified environment.
	*
	* <p>{@link ProcessBuilder#start()} is now the preferred way to
	* start a process with a modified environment.
	*
	* <p>The working directory of the new subprocess is specified by <tt>dir</tt>.
	* If <tt>dir</tt> is <tt>null</tt>, the subprocess inherits the
	* current working directory of the current process.
	*
	* <p>If a security manager exists, its
	* {@link SecurityManager#checkExec checkExec}
	* method is invoked with the first component of the array
	* <code>cmdarray</code> as its argument. This may result in a
	* {@link SecurityException} being thrown.
	*
	* <p>Starting an operating system process is highly system-dependent.
	* Among the many things that can go wrong are:
	* <ul>
	* <li>The operating system program file was not found.
	* <li>Access to the program file was denied.
	* <li>The working directory does not exist.
	* </ul>
	*
	* <p>In such cases an exception will be thrown. The exact nature
	* of the exception is system-dependent, but it will always be a
	* subclass of {@link IOException}.
	*
	*
	* @param cmdarray array containing the command to call and
	* its arguments.
	*
	* @param envp array of strings, each element of which
	* has environment variable settings in the format
	* <i>name</i>=<i>value</i>, or
	* <tt>null</tt> if the subprocess should inherit
	* the environment of the current process.
	*
	* @param dir the working directory of the subprocess, or
	* <tt>null</tt> if the subprocess should inherit
	* the working directory of the current process.
	*
	* @return A new {@link Process} object for managing the subprocess
	*
	* @throws SecurityException
	* If a security manager exists and its
	* {@link SecurityManager#checkExec checkExec}
	* method doesn't allow creation of the subprocess
	*
	* @throws IOException
	* If an I/O error occurs
	*
	* @throws NullPointerException
	* If <code>cmdarray</code> is <code>null</code>,
	* or one of the elements of <code>cmdarray</code> is <code>null</code>,
	* or one of the elements of <code>envp</code> is <code>null</code>
	*
	* @throws IndexOutOfBoundsException
	* If <code>cmdarray</code> is an empty array
	* (has length <code>0</code>)
	*
	* @see ProcessBuilder
	* @since 1.3
	*/
	public Process exec(String[] cmdarray, String[] envp, File dir)
	throws IOException {
	return new ProcessBuilder(cmdarray)
	.environment(envp)
	.directory(dir)
	.start();
	}

	/**
	* Returns the number of processors available to the Java virtual machine.
	*
	* <p> This value may change during a particular invocation of the virtual
	* machine. Applications that are sensitive to the number of available
	* processors should therefore occasionally poll this property and adjust
	* their resource usage appropriately. </p>
	*
	* @return the maximum number of processors available to the virtual
	* machine; never smaller than one
	* @since 1.4
	*/
	public native int availableProcessors();

	/**
	* Returns the amount of free memory in the Java Virtual Machine.
	* Calling the
	* <code>gc</code> method may result in increasing the value returned
	* by <code>freeMemory.</code>
	*
	* @return an approximation to the total amount of memory currently
	* available for future allocated objects, measured in bytes.
	*/
	public native long freeMemory();

	/**
	* Returns the total amount of memory in the Java virtual machine.
	* The value returned by this method may vary over time, depending on
	* the host environment.
	* <p>
	* Note that the amount of memory required to hold an object of any
	* given type may be implementation-dependent.
	*
	* @return the total amount of memory currently available for current
	* and future objects, measured in bytes.
	*/
	public native long totalMemory();

	/**
	* Returns the maximum amount of memory that the Java virtual machine will
	* attempt to use. If there is no inherent limit then the value {@link
	* java.lang.Long#MAX_VALUE} will be returned.
	*
	* @return the maximum amount of memory that the virtual machine will
	* attempt to use, measured in bytes
	* @since 1.4
	*/
	public native long maxMemory();

	/**
	* Runs the garbage collector.
	* Calling this method suggests that the Java virtual machine expend
	* effort toward recycling unused objects in order to make the memory
	* they currently occupy available for quick reuse. When control
	* returns from the method call, the virtual machine has made
	* its best effort to recycle all discarded objects.
	* <p>
	* The name <code>gc</code> stands for "garbage
	* collector". The virtual machine performs this recycling
	* process automatically as needed, in a separate thread, even if the
	* <code>gc</code> method is not invoked explicitly.
	* <p>
	* The method {@link System#gc()} is the conventional and convenient
	* means of invoking this method.
	*/
	public native void gc();

	/* Wormhole for calling java.lang.ref.Finalizer.runFinalization */
	private static native void runFinalization0();

	/**
	* Runs the finalization methods of any objects pending finalization.
	* Calling this method suggests that the Java virtual machine expend
	* effort toward running the <code>finalize</code> methods of objects
	* that have been found to be discarded but whose <code>finalize</code>
	* methods have not yet been run. When control returns from the
	* method call, the virtual machine has made a best effort to
	* complete all outstanding finalizations.
	* <p>
	* The virtual machine performs the finalization process
	* automatically as needed, in a separate thread, if the
	* <code>runFinalization</code> method is not invoked explicitly.
	* <p>
	* The method {@link System#runFinalization()} is the conventional
	* and convenient means of invoking this method.
	*
	* @see java.lang.Object#finalize()
	*/
	public void runFinalization() {
	runFinalization0();
	}

	/**
	* Enables/Disables tracing of instructions.
	* If the <code>boolean</code> argument is <code>true</code>, this
	* method suggests that the Java virtual machine emit debugging
	* information for each instruction in the virtual machine as it
	* is executed. The format of this information, and the file or other
	* output stream to which it is emitted, depends on the host environment.
	* The virtual machine may ignore this request if it does not support
	* this feature. The destination of the trace output is system
	* dependent.
	* <p>
	* If the <code>boolean</code> argument is <code>false</code>, this
	* method causes the virtual machine to stop performing the
	* detailed instruction trace it is performing.
	*
	* @param on <code>true</code> to enable instruction tracing;
	* <code>false</code> to disable this feature.
	*/
	public native void traceInstructions(boolean on);

	/**
	* Enables/Disables tracing of method calls.
	* If the <code>boolean</code> argument is <code>true</code>, this
	* method suggests that the Java virtual machine emit debugging
	* information for each method in the virtual machine as it is
	* called. The format of this information, and the file or other output
	* stream to which it is emitted, depends on the host environment. The
	* virtual machine may ignore this request if it does not support
	* this feature.
	* <p>
	* Calling this method with argument false suggests that the
	* virtual machine cease emitting per-call debugging information.
	*
	* @param on <code>true</code> to enable instruction tracing;
	* <code>false</code> to disable this feature.
	*/
	public native void traceMethodCalls(boolean on);

	/**
	* Loads the native library specified by the filename argument. The filename
	* argument must be an absolute path name.
	* (for example
	* <code>Runtime.getRuntime().load("/home/avh/lib/libX11.so");</code>).
	*
	* If the filename argument, when stripped of any platform-specific library
	* prefix, path, and file extension, indicates a library whose name is,
	* for example, L, and a native library called L is statically linked
	* with the VM, then the JNI_OnLoad_L function exported by the library
	* is invoked rather than attempting to load a dynamic library.
	* A filename matching the argument does not have to exist in the file
	* system. See the JNI Specification for more details.
	*
	* Otherwise, the filename argument is mapped to a native library image in
	* an implementation-dependent manner.
	* <p>
	* First, if there is a security manager, its <code>checkLink</code>
	* method is called with the <code>filename</code> as its argument.
	* This may result in a security exception.
	* <p>
	* This is similar to the method {@link #loadLibrary(String)}, but it
	* accepts a general file name as an argument rather than just a library
	* name, allowing any file of native code to be loaded.
	* <p>
	* The method {@link System#load(String)} is the conventional and
	* convenient means of invoking this method.
	*
	* @param filename the file to load.
	* @exception SecurityException if a security manager exists and its
	* <code>checkLink</code> method doesn't allow
	* loading of the specified dynamic library
	* @exception UnsatisfiedLinkError if either the filename is not an
	* absolute path name, the native library is not statically
	* linked with the VM, or the library cannot be mapped to
	* a native library image by the host system.
	* @exception NullPointerException if <code>filename</code> is
	* <code>null</code>
	* @see java.lang.Runtime#getRuntime()
	* @see java.lang.SecurityException
	* @see java.lang.SecurityManager#checkLink(java.lang.String)
	*/
	@CallerSensitive
	public void load(String filename) {
	load0(Reflection.getCallerClass(), filename);
	}

	synchronized void load0(Class<?> fromClass, String filename) {
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	security.checkLink(filename);
	}
	if (!(new File(filename).isAbsolute())) {
	throw new UnsatisfiedLinkError(
	"Expecting an absolute path of the library: " + filename);
	}
	ClassLoader.loadLibrary(fromClass, filename, true);
	}

	/**
	* Loads the native library specified by the <code>libname</code>
	* argument. The <code>libname</code> argument must not contain any platform
	* specific prefix, file extension or path. If a native library
	* called <code>libname</code> is statically linked with the VM, then the
	* JNI_OnLoad_<code>libname</code> function exported by the library is invoked.
	* See the JNI Specification for more details.
	*
	* Otherwise, the libname argument is loaded from a system library
	* location and mapped to a native library image in an implementation-
	* dependent manner.
	* <p>
	* First, if there is a security manager, its <code>checkLink</code>
	* method is called with the <code>libname</code> as its argument.
	* This may result in a security exception.
	* <p>
	* The method {@link System#loadLibrary(String)} is the conventional
	* and convenient means of invoking this method. If native
	* methods are to be used in the implementation of a class, a standard
	* strategy is to put the native code in a library file (call it
	* <code>LibFile</code>) and then to put a static initializer:
	* <blockquote><pre>
	* static { System.loadLibrary("LibFile"); }
	* </pre></blockquote>
	* within the class declaration. When the class is loaded and
	* initialized, the necessary native code implementation for the native
	* methods will then be loaded as well.
	* <p>
	* If this method is called more than once with the same library
	* name, the second and subsequent calls are ignored.
	*
	* @param libname the name of the library.
	* @exception SecurityException if a security manager exists and its
	* <code>checkLink</code> method doesn't allow
	* loading of the specified dynamic library
	* @exception UnsatisfiedLinkError if either the libname argument
	* contains a file path, the native library is not statically
	* linked with the VM, or the library cannot be mapped to a
	* native library image by the host system.
	* @exception NullPointerException if <code>libname</code> is
	* <code>null</code>
	* @see java.lang.SecurityException
	* @see java.lang.SecurityManager#checkLink(java.lang.String)
	*/
	@CallerSensitive
	public void loadLibrary(String libname) {
	loadLibrary0(Reflection.getCallerClass(), libname);
	}

	synchronized void loadLibrary0(Class<?> fromClass, String libname) {
	SecurityManager security = System.getSecurityManager();
	if (security != null) {
	security.checkLink(libname);
	}
	if (libname.indexOf((int)File.separatorChar) != -1) {
	throw new UnsatisfiedLinkError(
	"Directory separator should not appear in library name: " + libname);
	}
	ClassLoader.loadLibrary(fromClass, libname, false);
	}

	/**
	* Creates a localized version of an input stream. This method takes
	* an <code>InputStream</code> and returns an <code>InputStream</code>
	* equivalent to the argument in all respects except that it is
	* localized: as characters in the local character set are read from
	* the stream, they are automatically converted from the local
	* character set to Unicode.
	* <p>
	* If the argument is already a localized stream, it may be returned
	* as the result.
	*
	* @param in InputStream to localize
	* @return a localized input stream
	* @see java.io.InputStream
	* @see java.io.BufferedReader#BufferedReader(java.io.Reader)
	* @see java.io.InputStreamReader#InputStreamReader(java.io.InputStream)
	* @deprecated As of JDK 1.1, the preferred way to translate a byte
	* stream in the local encoding into a character stream in Unicode is via
	* the <code>InputStreamReader</code> and <code>BufferedReader</code>
	* classes.
	*/
	@Deprecated
	public InputStream getLocalizedInputStream(InputStream in) {
	return in;
	}

	/**
	* Creates a localized version of an output stream. This method
	* takes an <code>OutputStream</code> and returns an
	* <code>OutputStream</code> equivalent to the argument in all respects
	* except that it is localized: as Unicode characters are written to
	* the stream, they are automatically converted to the local
	* character set.
	* <p>
	* If the argument is already a localized stream, it may be returned
	* as the result.
	*
	* @deprecated As of JDK 1.1, the preferred way to translate a
	* Unicode character stream into a byte stream in the local encoding is via
	* the <code>OutputStreamWriter</code>, <code>BufferedWriter</code>, and
	* <code>PrintWriter</code> classes.
	*
	* @param out OutputStream to localize
	* @return a localized output stream
	* @see java.io.OutputStream
	* @see java.io.BufferedWriter#BufferedWriter(java.io.Writer)
	* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
	* @see java.io.PrintWriter#PrintWriter(java.io.OutputStream)
	*/
	@Deprecated
	public OutputStream getLocalizedOutputStream(OutputStream out) {
	return out;
	}

	}

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