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			797 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			Java
		
	
	
	
			
		
		
	
	
			797 lines
		
	
	
		
			28 KiB
		
	
	
	
		
			Java
		
	
	
	
| /* Runtime.java -- access to the VM process
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|    Copyright (C) 1998, 2002, 2003, 2004, 2005 Free Software Foundation
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| 
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| This file is part of GNU Classpath.
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| 
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| GNU Classpath is free software; you can redistribute it and/or modify
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| it under the terms of the GNU General Public License as published by
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| the Free Software Foundation; either version 2, or (at your option)
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| any later version.
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| 
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| GNU Classpath is distributed in the hope that it will be useful, but
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| WITHOUT ANY WARRANTY; without even the implied warranty of
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| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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| General Public License for more details.
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| 
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| You should have received a copy of the GNU General Public License
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| along with GNU Classpath; see the file COPYING.  If not, write to the
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| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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| 02110-1301 USA.
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| 
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| Linking this library statically or dynamically with other modules is
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| making a combined work based on this library.  Thus, the terms and
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| conditions of the GNU General Public License cover the whole
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| combination.
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| 
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| As a special exception, the copyright holders of this library give you
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| permission to link this library with independent modules to produce an
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| executable, regardless of the license terms of these independent
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| modules, and to copy and distribute the resulting executable under
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| terms of your choice, provided that you also meet, for each linked
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| independent module, the terms and conditions of the license of that
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| module.  An independent module is a module which is not derived from
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| or based on this library.  If you modify this library, you may extend
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| this exception to your version of the library, but you are not
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| obligated to do so.  If you do not wish to do so, delete this
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| exception statement from your version. */
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| 
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| 
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| package java.lang;
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| 
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| import gnu.classpath.SystemProperties;
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| import gnu.classpath.VMStackWalker;
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| 
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| import java.io.File;
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| import java.io.IOException;
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| import java.io.InputStream;
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| import java.io.OutputStream;
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| import java.util.HashSet;
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| import java.util.Iterator;
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| import java.util.Set;
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| import java.util.StringTokenizer;
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| 
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| /**
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|  * Runtime represents the Virtual Machine.
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|  *
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|  * @author John Keiser
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|  * @author Eric Blake (ebb9@email.byu.edu)
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|  * @author Jeroen Frijters
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|  */
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| // No idea why this class isn't final, since you can't build a subclass!
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| public class Runtime
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| {
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|   /**
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|    * The library path, to search when loading libraries. We can also safely use
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|    * this as a lock for synchronization.
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|    */
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|   private final String[] libpath;
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| 
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|   /**
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|    * The thread that started the exit sequence. Access to this field must
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|    * be thread-safe; lock on libpath to avoid deadlock with user code.
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|    * <code>runFinalization()</code> may want to look at this to see if ALL
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|    * finalizers should be run, because the virtual machine is about to halt.
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|    */
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|   private Thread exitSequence;
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| 
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|   /**
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|    * All shutdown hooks. This is initialized lazily, and set to null once all
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|    * shutdown hooks have run. Access to this field must be thread-safe; lock
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|    * on libpath to avoid deadlock with user code.
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|    */
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|   private Set shutdownHooks;
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| 
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|   /**
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|    * The one and only runtime instance.
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|    */
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|   private static final Runtime current = new Runtime();
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| 
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|   /**
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|    * Not instantiable by a user, this should only create one instance.
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|    */
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|   private Runtime()
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|   {
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|     if (current != null)
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|       throw new InternalError("Attempt to recreate Runtime");
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| 
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|     // If used by underlying VM this contains the directories where Classpath's own
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|     // native libraries are located.
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|     String bootPath = SystemProperties.getProperty("gnu.classpath.boot.library.path", "");
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| 
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|     // If properly set by the user this contains the directories where the application's
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|     // native libraries are located. On operating systems where a LD_LIBRARY_PATH environment
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|     // variable is available a VM should preset java.library.path with value of this
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|     // variable.
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|     String path = SystemProperties.getProperty("java.library.path", ".");
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|     String pathSep = SystemProperties.getProperty("path.separator", ":");
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|     String fileSep = SystemProperties.getProperty("file.separator", "/");
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| 
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|     StringTokenizer t1 = new StringTokenizer(bootPath, pathSep);
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|     StringTokenizer t2 = new StringTokenizer(path, pathSep);
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|     libpath = new String[t1.countTokens() + t2.countTokens()];
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| 
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|     int i = 0;
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|     while(t1.hasMoreTokens()) {
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|       String prefix = t1.nextToken();
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|       if (! prefix.endsWith(fileSep))
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|         prefix += fileSep;
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| 
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|       libpath[i] = prefix;
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|       i++;
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|     }
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| 
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|     while(t2.hasMoreTokens()) {
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|       String prefix = t2.nextToken();
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|       if (! prefix.endsWith(fileSep))
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|         prefix += fileSep;
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| 
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|       libpath[i] = prefix;
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|       i++;
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|     }
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|   }
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| 
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|   /**
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|    * Get the current Runtime object for this JVM. This is necessary to access
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|    * the many instance methods of this class.
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|    *
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|    * @return the current Runtime object
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|    */
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|   public static Runtime getRuntime()
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|   {
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|     return current;
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|   }
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| 
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|   /**
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|    * Exit the Java runtime. This method will either throw a SecurityException
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|    * or it will never return. The status code is returned to the system; often
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|    * a non-zero status code indicates an abnormal exit. Of course, there is a
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|    * security check, <code>checkExit(status)</code>.
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|    *
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|    * <p>First, all shutdown hooks are run, in unspecified order, and
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|    * concurrently. Next, if finalization on exit has been enabled, all pending
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|    * finalizers are run. Finally, the system calls <code>halt</code>.</p>
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|    *
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|    * <p>If this is run a second time after shutdown has already started, there
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|    * are two actions. If shutdown hooks are still executing, it blocks
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|    * indefinitely. Otherwise, if the status is nonzero it halts immediately;
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|    * if it is zero, it blocks indefinitely. This is typically called by
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|    * <code>System.exit</code>.</p>
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|    *
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|    * @param status the status to exit with
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|    * @throws SecurityException if permission is denied
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|    * @see #addShutdownHook(Thread)
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|    * @see #runFinalizersOnExit(boolean)
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|    * @see #runFinalization()
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|    * @see #halt(int)
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|    */
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|   public void exit(int status)
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|   {
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|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
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|     if (sm != null)
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|       sm.checkExit(status);
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| 
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|     if (runShutdownHooks())
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|       halt(status);
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| 
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|     // Someone else already called runShutdownHooks().
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|     // Make sure we are not/no longer in the shutdownHooks set.
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|     // And wait till the thread that is calling runShutdownHooks() finishes.
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|     synchronized (libpath)
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|       {
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|         if (shutdownHooks != null)
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|           {
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|             shutdownHooks.remove(Thread.currentThread());
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|             // Interrupt the exit sequence thread, in case it was waiting
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|             // inside a join on our thread.
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|             exitSequence.interrupt();
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|             // Shutdown hooks are still running, so we clear status to
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|             // make sure we don't halt.
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|             status = 0;
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|           }
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|       }
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| 
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|     // If exit() is called again after the shutdown hooks have run, but
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|     // while finalization for exit is going on and the status is non-zero
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|     // we halt immediately.
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|     if (status != 0)
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|       halt(status);
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| 
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|     while (true)
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|       try
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|         {
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|           exitSequence.join();
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|         }
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|       catch (InterruptedException e)
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|         {
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|           // Ignore, we've suspended indefinitely to let all shutdown
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|           // hooks complete, and to let any non-zero exits through, because
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|           // this is a duplicate call to exit(0).
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|         }
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|   }
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| 
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|   /**
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|    * On first invocation, run all the shutdown hooks and return true.
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|    * Any subsequent invocations will simply return false.
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|    * Note that it is package accessible so that VMRuntime can call it
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|    * when VM exit is not triggered by a call to Runtime.exit().
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|    *
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|    * @return was the current thread the first one to call this method?
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|    */
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|   boolean runShutdownHooks()
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|   {
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|     boolean first = false;
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|     synchronized (libpath) // Synch on libpath, not this, to avoid deadlock.
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|       {
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|         if (exitSequence == null)
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|           {
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|             first = true;
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|             exitSequence = Thread.currentThread();
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|             if (shutdownHooks != null)
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|               {
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|                 Iterator i = shutdownHooks.iterator();
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|                 while (i.hasNext()) // Start all shutdown hooks.
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|                   try
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|                     {
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|                       ((Thread) i.next()).start();
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|                     }
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|                   catch (IllegalThreadStateException e)
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|                     {
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|                       i.remove();
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|                     }
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|               }
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|           }
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|       }
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|     if (first)
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|       {
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|         if (shutdownHooks != null)
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|           {
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|             // Check progress of all shutdown hooks. As a hook completes,
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|             // remove it from the set. If a hook calls exit, it removes
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|             // itself from the set, then waits indefinitely on the
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|             // exitSequence thread. Once the set is empty, set it to null to
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|             // signal all finalizer threads that halt may be called.
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|             while (true)
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|               {
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|                 Thread[] hooks;
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|                 synchronized (libpath)
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|                   {
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|                     hooks = new Thread[shutdownHooks.size()];
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|                     shutdownHooks.toArray(hooks);
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|                   }
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|                 if (hooks.length == 0)
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|                   break;
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|                 for (int i = 0; i < hooks.length; i++)
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|                   {
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|                     try
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|                       {
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|                         synchronized (libpath)
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|                           {
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|                             if (!shutdownHooks.contains(hooks[i]))
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|                               continue;
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|                           }
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|                         hooks[i].join();
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|                         synchronized (libpath)
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|                           {
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|                             shutdownHooks.remove(hooks[i]);
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|                           }
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|                       }
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|                     catch (InterruptedException x)
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|                       {
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|                         // continue waiting on the next thread
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|                       }
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|                   }
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|               }
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|             synchronized (libpath)
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|               {
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|                 shutdownHooks = null;
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|               }
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|           }
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|         // Run finalization on all finalizable objects (even if they are
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|         // still reachable).
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|         VMRuntime.runFinalizationForExit();
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|       }
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|     return first;
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|   }
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| 
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|   /**
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|    * Register a new shutdown hook. This is invoked when the program exits
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|    * normally (because all non-daemon threads ended, or because
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|    * <code>System.exit</code> was invoked), or when the user terminates
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|    * the virtual machine (such as by typing ^C, or logging off). There is
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|    * a security check to add hooks,
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|    * <code>RuntimePermission("shutdownHooks")</code>.
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|    *
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|    * <p>The hook must be an initialized, but unstarted Thread. The threads
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|    * are run concurrently, and started in an arbitrary order; and user
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|    * threads or daemons may still be running. Once shutdown hooks have
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|    * started, they must all complete, or else you must use <code>halt</code>,
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|    * to actually finish the shutdown sequence. Attempts to modify hooks
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|    * after shutdown has started result in IllegalStateExceptions.</p>
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|    *
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|    * <p>It is imperative that you code shutdown hooks defensively, as you
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|    * do not want to deadlock, and have no idea what other hooks will be
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|    * running concurrently. It is also a good idea to finish quickly, as the
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|    * virtual machine really wants to shut down!</p>
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|    *
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|    * <p>There are no guarantees that such hooks will run, as there are ways
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|    * to forcibly kill a process. But in such a drastic case, shutdown hooks
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|    * would do little for you in the first place.</p>
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|    *
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|    * @param hook an initialized, unstarted Thread
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|    * @throws IllegalArgumentException if the hook is already registered or run
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|    * @throws IllegalStateException if the virtual machine is already in
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|    *         the shutdown sequence
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|    * @throws SecurityException if permission is denied
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|    * @since 1.3
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|    * @see #removeShutdownHook(Thread)
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|    * @see #exit(int)
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|    * @see #halt(int)
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|    */
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|   public void addShutdownHook(Thread hook)
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|   {
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|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
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|     if (sm != null)
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|       sm.checkPermission(new RuntimePermission("shutdownHooks"));
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|     if (hook.isAlive() || hook.getThreadGroup() == null)
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|       throw new IllegalArgumentException("The hook thread " + hook + " must not have been already run or started");
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|     synchronized (libpath)
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|       {
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|         if (exitSequence != null)
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|           throw new IllegalStateException("The Virtual Machine is exiting. It is not possible anymore to add any hooks");
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|         if (shutdownHooks == null)
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|           {
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|             VMRuntime.enableShutdownHooks();
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|             shutdownHooks = new HashSet(); // Lazy initialization.
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|           }
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|         if (! shutdownHooks.add(hook))
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|           throw new IllegalArgumentException(hook.toString() + " had already been inserted");
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|       }
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|   }
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| 
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|   /**
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|    * De-register a shutdown hook. As when you registered it, there is a
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|    * security check to remove hooks,
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|    * <code>RuntimePermission("shutdownHooks")</code>.
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|    *
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|    * @param hook the hook to remove
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|    * @return true if the hook was successfully removed, false if it was not
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|    *         registered in the first place
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|    * @throws IllegalStateException if the virtual machine is already in
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|    *         the shutdown sequence
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|    * @throws SecurityException if permission is denied
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|    * @since 1.3
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|    * @see #addShutdownHook(Thread)
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|    * @see #exit(int)
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|    * @see #halt(int)
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|    */
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|   public boolean removeShutdownHook(Thread hook)
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|   {
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|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
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|     if (sm != null)
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|       sm.checkPermission(new RuntimePermission("shutdownHooks"));
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|     synchronized (libpath)
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|       {
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|         if (exitSequence != null)
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|           throw new IllegalStateException();
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|         if (shutdownHooks != null)
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|           return shutdownHooks.remove(hook);
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|       }
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|     return false;
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|   }
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| 
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|   /**
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|    * Forcibly terminate the virtual machine. This call never returns. It is
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|    * much more severe than <code>exit</code>, as it bypasses all shutdown
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|    * hooks and initializers. Use caution in calling this! Of course, there is
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|    * a security check, <code>checkExit(status)</code>.
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|    *
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|    * @param status the status to exit with
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|    * @throws SecurityException if permission is denied
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|    * @since 1.3
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|    * @see #exit(int)
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|    * @see #addShutdownHook(Thread)
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|    */
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|   public void halt(int status)
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|   {
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|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
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|     if (sm != null)
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|       sm.checkExit(status);
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|     VMRuntime.exit(status);
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|   }
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| 
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|   /**
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|    * Tell the VM to run the finalize() method on every single Object before
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|    * it exits.  Note that the JVM may still exit abnormally and not perform
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|    * this, so you still don't have a guarantee. And besides that, this is
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|    * inherently unsafe in multi-threaded code, as it may result in deadlock
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|    * as multiple threads compete to manipulate objects. This value defaults to
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|    * <code>false</code>. There is a security check, <code>checkExit(0)</code>.
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|    *
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|    * @param finalizeOnExit whether to finalize all Objects on exit
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|    * @throws SecurityException if permission is denied
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|    * @see #exit(int)
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|    * @see #gc()
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|    * @since 1.1
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|    * @deprecated never rely on finalizers to do a clean, thread-safe,
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|    *             mop-up from your code
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|    */
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|   public static void runFinalizersOnExit(boolean finalizeOnExit)
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|   {
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|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
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|     if (sm != null)
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|       sm.checkExit(0);
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|     VMRuntime.runFinalizersOnExit(finalizeOnExit);
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|   }
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| 
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|   /**
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|    * Create a new subprocess with the specified command line. Calls
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|    * <code>exec(cmdline, null, null)</code>. A security check is performed,
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|    * <code>checkExec</code>.
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|    *
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|    * @param cmdline the command to call
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|    * @return the Process object
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|    * @throws SecurityException if permission is denied
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|    * @throws IOException if an I/O error occurs
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|    * @throws NullPointerException if cmdline is null
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|    * @throws IndexOutOfBoundsException if cmdline is ""
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|    */
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|   public Process exec(String cmdline) throws IOException
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|   {
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|     return exec(cmdline, null, null);
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|   }
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| 
 | |
|   /**
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|    * Create a new subprocess with the specified command line and environment.
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|    * If the environment is null, the process inherits the environment of
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|    * this process. Calls <code>exec(cmdline, env, null)</code>. A security
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|    * check is performed, <code>checkExec</code>.
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|    *
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|    * @param cmdline the command to call
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|    * @param env the environment to use, in the format name=value
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|    * @return the Process object
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|    * @throws SecurityException if permission is denied
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|    * @throws IOException if an I/O error occurs
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|    * @throws NullPointerException if cmdline is null, or env has null entries
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|    * @throws IndexOutOfBoundsException if cmdline is ""
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|    */
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|   public Process exec(String cmdline, String[] env) throws IOException
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|   {
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|     return exec(cmdline, env, null);
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|   }
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| 
 | |
|   /**
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|    * Create a new subprocess with the specified command line, environment, and
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|    * working directory. If the environment is null, the process inherits the
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|    * environment of this process. If the directory is null, the process uses
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|    * the current working directory. This splits cmdline into an array, using
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|    * the default StringTokenizer, then calls
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|    * <code>exec(cmdArray, env, dir)</code>. A security check is performed,
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|    * <code>checkExec</code>.
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|    *
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|    * @param cmdline the command to call
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|    * @param env the environment to use, in the format name=value
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|    * @param dir the working directory to use
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|    * @return the Process object
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|    * @throws SecurityException if permission is denied
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|    * @throws IOException if an I/O error occurs
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|    * @throws NullPointerException if cmdline is null, or env has null entries
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|    * @throws IndexOutOfBoundsException if cmdline is ""
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|    * @since 1.3
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|    */
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|   public Process exec(String cmdline, String[] env, File dir)
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|     throws IOException
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|   {
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|     StringTokenizer t = new StringTokenizer(cmdline);
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|     String[] cmd = new String[t.countTokens()];
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|     for (int i = 0; i < cmd.length; i++)
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|       cmd[i] = t.nextToken();
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|     return exec(cmd, env, dir);
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|   }
 | |
| 
 | |
|   /**
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|    * Create a new subprocess with the specified command line, already
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|    * tokenized. Calls <code>exec(cmd, null, null)</code>. A security check
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|    * is performed, <code>checkExec</code>.
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|    *
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|    * @param cmd the command to call
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|    * @return the Process object
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|    * @throws SecurityException if permission is denied
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|    * @throws IOException if an I/O error occurs
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|    * @throws NullPointerException if cmd is null, or has null entries
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|    * @throws IndexOutOfBoundsException if cmd is length 0
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|    */
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|   public Process exec(String[] cmd) throws IOException
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|   {
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|     return exec(cmd, null, null);
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|   }
 | |
| 
 | |
|   /**
 | |
|    * Create a new subprocess with the specified command line, already
 | |
|    * tokenized, and specified environment. If the environment is null, the
 | |
|    * process inherits the environment of this process. Calls
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|    * <code>exec(cmd, env, null)</code>. A security check is performed,
 | |
|    * <code>checkExec</code>.
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|    *
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|    * @param cmd the command to call
 | |
|    * @param env the environment to use, in the format name=value
 | |
|    * @return the Process object
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws IOException if an I/O error occurs
 | |
|    * @throws NullPointerException if cmd is null, or cmd or env has null
 | |
|    *         entries
 | |
|    * @throws IndexOutOfBoundsException if cmd is length 0
 | |
|    */
 | |
|   public Process exec(String[] cmd, String[] env) throws IOException
 | |
|   {
 | |
|     return exec(cmd, env, null);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Create a new subprocess with the specified command line, already
 | |
|    * tokenized, and the specified environment and working directory. If the
 | |
|    * environment is null, the process inherits the environment of this
 | |
|    * process. If the directory is null, the process uses the current working
 | |
|    * directory. A security check is performed, <code>checkExec</code>.
 | |
|    *
 | |
|    * @param cmd the command to call
 | |
|    * @param env the environment to use, in the format name=value
 | |
|    * @param dir the working directory to use
 | |
|    * @return the Process object
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws IOException if an I/O error occurs
 | |
|    * @throws NullPointerException if cmd is null, or cmd or env has null
 | |
|    *         entries
 | |
|    * @throws IndexOutOfBoundsException if cmd is length 0
 | |
|    * @since 1.3
 | |
|    */
 | |
|   public Process exec(String[] cmd, String[] env, File dir)
 | |
|     throws IOException
 | |
|   {
 | |
|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
 | |
|     if (sm != null)
 | |
|       sm.checkExec(cmd[0]);
 | |
|     return VMRuntime.exec(cmd, env, dir);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Returns the number of available processors currently available to the
 | |
|    * virtual machine. This number may change over time; so a multi-processor
 | |
|    * program want to poll this to determine maximal resource usage.
 | |
|    *
 | |
|    * @return the number of processors available, at least 1
 | |
|    */
 | |
|   public int availableProcessors()
 | |
|   {
 | |
|     return VMRuntime.availableProcessors();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Find out how much memory is still free for allocating Objects on the heap.
 | |
|    *
 | |
|    * @return the number of bytes of free memory for more Objects
 | |
|    */
 | |
|   public long freeMemory()
 | |
|   {
 | |
|     return VMRuntime.freeMemory();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Find out how much memory total is available on the heap for allocating
 | |
|    * Objects.
 | |
|    *
 | |
|    * @return the total number of bytes of memory for Objects
 | |
|    */
 | |
|   public long totalMemory()
 | |
|   {
 | |
|     return VMRuntime.totalMemory();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Returns the maximum amount of memory the virtual machine can attempt to
 | |
|    * use. This may be <code>Long.MAX_VALUE</code> if there is no inherent
 | |
|    * limit (or if you really do have a 8 exabyte memory!).
 | |
|    *
 | |
|    * @return the maximum number of bytes the virtual machine will attempt
 | |
|    *         to allocate
 | |
|    */
 | |
|   public long maxMemory()
 | |
|   {
 | |
|     return VMRuntime.maxMemory();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Run the garbage collector. This method is more of a suggestion than
 | |
|    * anything. All this method guarantees is that the garbage collector will
 | |
|    * have "done its best" by the time it returns. Notice that garbage
 | |
|    * collection takes place even without calling this method.
 | |
|    */
 | |
|   public void gc()
 | |
|   {
 | |
|     VMRuntime.gc();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Run finalization on all Objects that are waiting to be finalized. Again,
 | |
|    * a suggestion, though a stronger one than {@link #gc()}. This calls the
 | |
|    * <code>finalize</code> method of all objects waiting to be collected.
 | |
|    *
 | |
|    * @see #finalize()
 | |
|    */
 | |
|   public void runFinalization()
 | |
|   {
 | |
|     VMRuntime.runFinalization();
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Tell the VM to trace every bytecode instruction that executes (print out
 | |
|    * a trace of it).  No guarantees are made as to where it will be printed,
 | |
|    * and the VM is allowed to ignore this request.
 | |
|    *
 | |
|    * @param on whether to turn instruction tracing on
 | |
|    */
 | |
|   public void traceInstructions(boolean on)
 | |
|   {
 | |
|     VMRuntime.traceInstructions(on);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Tell the VM to trace every method call that executes (print out a trace
 | |
|    * of it).  No guarantees are made as to where it will be printed, and the
 | |
|    * VM is allowed to ignore this request.
 | |
|    *
 | |
|    * @param on whether to turn method tracing on
 | |
|    */
 | |
|   public void traceMethodCalls(boolean on)
 | |
|   {
 | |
|     VMRuntime.traceMethodCalls(on);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Load a native library using the system-dependent filename. This is similar
 | |
|    * to loadLibrary, except the only name mangling done is inserting "_g"
 | |
|    * before the final ".so" if the VM was invoked by the name "java_g". There
 | |
|    * may be a security check, of <code>checkLink</code>.
 | |
|    *
 | |
|    * <p>
 | |
|    * The library is loaded using the class loader associated with the
 | |
|    * class associated with the invoking method.
 | |
|    *
 | |
|    * @param filename the file to load
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws UnsatisfiedLinkError if the library is not found
 | |
|    */
 | |
|   public void load(String filename)
 | |
|   {
 | |
|     load(filename, VMStackWalker.getCallingClassLoader());
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Same as <code>load(String)</code> but using the given loader.
 | |
|    *
 | |
|    * @param filename the file to load
 | |
|    * @param loader class loader, or <code>null</code> for the boot loader
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws UnsatisfiedLinkError if the library is not found
 | |
|    */
 | |
|   void load(String filename, ClassLoader loader)
 | |
|   {
 | |
|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
 | |
|     if (sm != null)
 | |
|       sm.checkLink(filename);
 | |
|     if (loadLib(filename, loader) == 0)
 | |
|       throw new UnsatisfiedLinkError("Could not load library " + filename);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Do a security check on the filename and then load the native library.
 | |
|    *
 | |
|    * @param filename the file to load
 | |
|    * @param loader class loader, or <code>null</code> for the boot loader
 | |
|    * @return 0 on failure, nonzero on success
 | |
|    * @throws SecurityException if file read permission is denied
 | |
|    */
 | |
|   private static int loadLib(String filename, ClassLoader loader)
 | |
|   {
 | |
|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
 | |
|     if (sm != null)
 | |
|       sm.checkRead(filename);
 | |
|     return VMRuntime.nativeLoad(filename, loader);
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Load a native library using a system-independent "short name" for the
 | |
|    * library.  It will be transformed to a correct filename in a
 | |
|    * system-dependent manner (for example, in Windows, "mylib" will be turned
 | |
|    * into "mylib.dll").  This is done as follows: if the context that called
 | |
|    * load has a ClassLoader cl, then <code>cl.findLibrary(libpath)</code> is
 | |
|    * used to convert the name. If that result was null, or there was no class
 | |
|    * loader, this searches each directory of the system property
 | |
|    * <code>java.library.path</code> for a file named
 | |
|    * <code>System.mapLibraryName(libname)</code>. There may be a security
 | |
|    * check, of <code>checkLink</code>.
 | |
|    *
 | |
|    * <p>Note: Besides <code>java.library.path</code> a VM may chose to search
 | |
|    * for native libraries in a path that is specified by the
 | |
|    * <code>gnu.classpath.boot.library.path</code> system property. However
 | |
|    * this is for internal usage or development of GNU Classpath only.
 | |
|    * <b>A Java application must not load a non-system library by changing
 | |
|    * this property otherwise it will break compatibility.</b></p>
 | |
|    *
 | |
|    * <p>
 | |
|    * The library is loaded using the class loader associated with the
 | |
|    * class associated with the invoking method.
 | |
|    *
 | |
|    * @param libname the library to load
 | |
|    *
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws UnsatisfiedLinkError if the library is not found
 | |
|    *
 | |
|    * @see System#mapLibraryName(String)
 | |
|    * @see ClassLoader#findLibrary(String)
 | |
|    */
 | |
|   public void loadLibrary(String libname)
 | |
|   {
 | |
|     loadLibrary(libname, VMStackWalker.getCallingClassLoader());
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Same as <code>loadLibrary(String)</code> but using the given loader.
 | |
|    *
 | |
|    * @param libname the library to load
 | |
|    * @param loader class loader, or <code>null</code> for the boot loader
 | |
|    * @throws SecurityException if permission is denied
 | |
|    * @throws UnsatisfiedLinkError if the library is not found
 | |
|    */
 | |
|   void loadLibrary(String libname, ClassLoader loader)
 | |
|   {
 | |
|     SecurityManager sm = SecurityManager.current; // Be thread-safe!
 | |
|     if (sm != null)
 | |
|       sm.checkLink(libname);
 | |
|     String filename;
 | |
|     if (loader != null && (filename = loader.findLibrary(libname)) != null)
 | |
|       {
 | |
|         if (loadLib(filename, loader) != 0)
 | |
|           return;
 | |
|       }
 | |
|     else
 | |
|       {
 | |
|         filename = VMRuntime.mapLibraryName(libname);
 | |
|         for (int i = 0; i < libpath.length; i++)
 | |
|           if (loadLib(libpath[i] + filename, loader) != 0)
 | |
|             return;
 | |
|       }
 | |
|     throw new UnsatisfiedLinkError("Native library `" + libname
 | |
|       + "' not found (as file `" + filename + "') in gnu.classpath.boot.library.path and java.library.path");
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Return a localized version of this InputStream, meaning all characters
 | |
|    * are localized before they come out the other end.
 | |
|    *
 | |
|    * @param in the stream to localize
 | |
|    * @return the localized stream
 | |
|    * @deprecated <code>InputStreamReader</code> is the preferred way to read
 | |
|    *             local encodings
 | |
|    * @XXX This implementation does not localize, yet.
 | |
|    */
 | |
|   public InputStream getLocalizedInputStream(InputStream in)
 | |
|   {
 | |
|     return in;
 | |
|   }
 | |
| 
 | |
|   /**
 | |
|    * Return a localized version of this OutputStream, meaning all characters
 | |
|    * are localized before they are sent to the other end.
 | |
|    *
 | |
|    * @param out the stream to localize
 | |
|    * @return the localized stream
 | |
|    * @deprecated <code>OutputStreamWriter</code> is the preferred way to write
 | |
|    *             local encodings
 | |
|    * @XXX This implementation does not localize, yet.
 | |
|    */
 | |
|   public OutputStream getLocalizedOutputStream(OutputStream out)
 | |
|   {
 | |
|     return out;
 | |
|   }
 | |
| } // class Runtime
 |