Fixes PR libgcj/6389:

	* Makefile.in: Rebuilt.
	* Makefile.am (nat_source_files): Added natTimeZone.cc.
	* java/util/natTimeZone.cc: New file.
	* java/util/TimeZone.java (getDefaultTimeZoneId): New method.
	* java/lang/System.java: Merged with Classpath.
	* java/lang/Runtime.java: Merged with Classpath.
	* java/lang/natSystem.cc (setErr0): Renamed from setErr; don't run
	security check.
	(setIn0): Renamed from setIn; don't run security check.
	(setOut0): Renamed from setOut; don't run security check.
	(file_encoding, getpwuid_adaptor, getSystemTimeZone,
	init_properties): Moved to natRuntime.cc.
	Moved many includes to natRuntime.cc.
	(isWordsBigEndian): New method.
	* java/lang/natRuntime.cc: Include Long.h, also other includes
	previously in natSystem.cc.
	(maxMemory): New function.
	(exitInternal): Renamed from `_exit'.
	(exit): Removed.
	(init): Don't set finalize_on_exit.
	(exitInternal): Use `finalizeOnExit'.
	(file_encoding, getpwuid_adaptor): New functions from
	natSystem.cc.
	(insertSystemProperties): New method, renamed from
	System::init_properties.  Don't set user.timezone.
	(_load): Don't call checkLink.
	(execInternal): New method.
	(availableProcessors): Likewise.
	(nativeGetLibname): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@53429 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 725 insertions, 87 deletions

diff --git a/libjava/java/lang/Runtime.java b/libjava/java/lang/Runtime.java
index 28befc26d19..65f73a337be 100644
--- a/libjava/java/lang/Runtime.java
+++ b/libjava/java/lang/Runtime.java
@@ -1,147 +1,785 @@
-// Runtime.java - Runtime class.
+/* Runtime.java -- access to the VM process
+   Copyright (C) 1998, 2002 Free Software Foundation
 
-/* Copyright (C) 1998, 1999, 2000, 2001  Free Software Foundation
+This file is part of GNU Classpath.
 
-   This file is part of libgcj.
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
 
-This software is copyrighted work licensed under the terms of the
-Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
-details.  */
+GNU Classpath 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 for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
 
 package java.lang;
 
-import java.io.IOException;
+import java.io.File;
 import java.io.InputStream;
+import java.io.IOException;
 import java.io.OutputStream;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.Properties;
+import java.util.Set;
 import java.util.StringTokenizer;
 
 /**
- * @author Tom Tromey <tromey@cygnus.com>
- * @date August 27, 1998 
+ * Runtime represents the Virtual Machine.
+ *
+ * @author John Keiser
+ * @author Eric Blake <ebb9@email.byu.edu>
+ * @status still missing 1.4 functionality
  */
-
-/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
- * "The Java Language Specification", ISBN 0-201-63451-1
- * plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
- * Status:  All 1.1 methods exist.  exec() is not fully implemented.
- */
-
+// No idea why this class isn't final, since you can't build a subclass!
 public class Runtime
 {
-  public Process exec (String prog) throws IOException
+  /**
+   * The library path, to search when loading libraries. We can also safely use
+   * this as a lock for synchronization.
+   */
+  private final String[] libpath;
+
+  /**
+   * The current security manager. This is located here instead of in
+   * Runtime, to avoid security problems, as well as bootstrap issues.
+   * Make sure to access it in a thread-safe manner; it is package visible
+   * to avoid overhead in java.lang.
+   */
+  static SecurityManager securityManager;
+
+  /**
+   * The default properties defined by the system. This is likewise located
+   * here instead of in Runtime, to avoid bootstrap issues; it is package
+   * visible to avoid overhead in java.lang. Note that System will add a
+   * few more properties to this collection, but that after that, it is
+   * treated as read-only.
+   *
+   * No matter what class you start initialization with, it defers to the
+   * superclass, therefore Object.<clinit> will be the first Java code
+   * executed. From there, the bootstrap sequence, up to the point that
+   * native libraries are loaded (as of March 24, when I traced this
+   * manually) is as follows:
+   *
+   * Object.<clinit> uses a String literal, possibly triggering initialization
+   *  String.<clinit> calls WeakHashMap.<init>, triggering initialization
+   *   AbstractMap, WeakHashMap, WeakHashMap$1 have no dependencies
+   *  String.<clinit> calls CaseInsensitiveComparator.<init>, triggering
+   *      initialization
+   *   CaseInsensitiveComparator has no dependencies
+   * Object.<clinit> calls System.loadLibrary, triggering initialization
+   *  System.<clinit> calls System.loadLibrary
+   *  System.loadLibrary calls Runtime.getRuntime, triggering initialization
+   *   Runtime.<clinit> calls Properties.<init>, triggering initialization
+   *    Dictionary, Hashtable, and Properties have no dependencies
+   *   Runtime.<clinit> calls insertSystemProperties; the VM must make sure
+   *      that there are not any harmful dependencies
+   *   Runtime.<clinit> calls Runtime.<init>
+   *    Runtime.<init> calls StringTokenizer.<init>, triggering initialization
+   *     StringTokenizer has no dependencies
+   *  System.loadLibrary calls Runtime.loadLibrary
+   *   Runtime.loadLibrary should be able to load the library, although it
+   *       will probably set off another string of initializations from
+   *       ClassLoader first
+   */
+  static Properties defaultProperties = new Properties();
+  static
   {
-    return exec (prog, null);
+    insertSystemProperties(defaultProperties);
   }
 
-  public Process exec (String prog, String[] envp) throws IOException
+  /**
+   * The thread that started the exit sequence. Access to this field must
+   * be thread-safe; lock on libpath to avoid deadlock with user code.
+   * <code>runFinalization()</code> may want to look at this to see if ALL
+   * finalizers should be run, because the virtual machine is about to halt.
+   */
+  private Thread exitSequence;
+
+  /**
+   * All shutdown hooks. This is initialized lazily, and set to null once all
+   * shutdown hooks have run. Access to this field must be thread-safe; lock
+   * on libpath to avoid deadlock with user code.
+   */
+  private Set shutdownHooks;
+
+  /** True if we should finalize on exit.  */
+  private boolean finalizeOnExit;
+
+  /**
+   * The one and only runtime instance. This must appear after the default
+   * properties have been initialized by the VM.
+   */
+  private static final Runtime current = new Runtime();
+
+  /**
+   * Not instantiable by a user, this should only create one instance.
+   */
+  private Runtime()
   {
-    StringTokenizer st = new StringTokenizer(prog);
-    String[] a = new String[st.countTokens ()];
-    for (int i = 0; i < a.length; i++)
-      a[i] = st.nextToken ();
-    return exec (a, envp);
+    if (current != null)
+      throw new InternalError("Attempt to recreate Runtime");
+
+    // We don't use libpath in the libgcj implementation.  We still
+    // set it to something to allow the various synchronizations to
+    // work.
+    libpath = new String[0];
+
+    init ();
   }
 
-  public Process exec (String[] progarray) throws IOException
+  /**
+   * Get the current Runtime object for this JVM. This is necessary to access
+   * the many instance methods of this class.
+   *
+   * @return the current Runtime object
+   */
+  public static Runtime getRuntime()
   {
-    return exec (progarray, null);
+    return current;
   }
 
-  public Process exec (String[] progarray, String[] envp) throws IOException
+  /**
+   * Exit the Java runtime. This method will either throw a SecurityException
+   * or it will never return. The status code is returned to the system; often
+   * a non-zero status code indicates an abnormal exit. Of course, there is a
+   * security check, <code>checkExit(status)</code>.
+   *
+   * <p>First, all shutdown hooks are run, in unspecified order, and
+   * concurrently. Next, if finalization on exit has been enabled, all pending
+   * finalizers are run. Finally, the system calls <code>halt</code>.
+   *
+   * <p>If this is run a second time after shutdown has already started, there
+   * are two actions. If shutdown hooks are still executing, it blocks
+   * indefinitely. Otherwise, if the status is nonzero it halts immediately;
+   * if it is zero, it blocks indefinitely. This is typically called by
+   * <code>System.exit</code>.
+   *
+   * @param status the status to exit with
+   * @throws SecurityException if permission is denied
+   * @see #addShutdownHook(Thread)
+   * @see #runFinalizersOnExit(boolean)
+   * @see #runFinalization()
+   * @see #halt(int)
+   */
+  public void exit(int status)
   {
-    SecurityManager s = System.getSecurityManager();
-    if (s != null)
-      s.checkExec(progarray[0]);
-    return new ConcreteProcess (progarray, envp);
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkExit(status);
+    boolean first = false;
+    synchronized (libpath) // Synch on libpath, not this, to avoid deadlock.
+      {
+        if (exitSequence == null)
+          {
+            first = true;
+            exitSequence = Thread.currentThread();
+            if (shutdownHooks != null)
+              {
+                Iterator i = shutdownHooks.iterator();
+                while (i.hasNext()) // Start all shutdown hooks.
+                  try
+                    {
+                      ((Thread) i.next()).start();
+                    }
+                  catch (IllegalThreadStateException e)
+                    {
+                      i.remove();
+                    }
+              }
+          }
+      }
+    if (first)
+      {
+        if (shutdownHooks != null)
+          {
+            // Check progress of all shutdown hooks. As a hook completes,
+            // remove it from the set. If a hook calls exit, it removes
+            // itself from the set, then waits indefinitely on the
+            // exitSequence thread. Once the set is empty, set it to null to
+            // signal all finalizer threads that halt may be called.
+            while (! shutdownHooks.isEmpty())
+              {
+                Thread[] hooks;
+                synchronized (libpath)
+                  {
+                    hooks = new Thread[shutdownHooks.size()];
+                    shutdownHooks.toArray(hooks);
+                  }
+                for (int i = hooks.length; --i >= 0; )
+                  if (! hooks[i].isAlive())
+                    synchronized (libpath)
+                      {
+                        shutdownHooks.remove(hooks[i]);
+                      }
+                try
+                  {
+                    exitSequence.sleep(1); // Give other threads a chance.
+                  }
+                catch (InterruptedException e)
+                  {
+                    // Ignore, the next loop just starts sooner.
+                  }
+              }
+            synchronized (libpath)
+              {
+                shutdownHooks = null;
+              }
+          }
+        // XXX Right now, it is the VM that knows whether runFinalizersOnExit
+        // is true; so the VM must look at exitSequence to decide whether
+        // this should be run on every object.
+        runFinalization();
+      }
+    else
+      synchronized (libpath)
+        {
+          if (shutdownHooks != null)
+            {
+              shutdownHooks.remove(Thread.currentThread());
+              status = 0; // Change status to enter indefinite wait.
+            }
+        }
+    
+    if (first || status > 0)
+      halt(status);
+    while (true)
+      try
+        {
+          exitSequence.join();
+        }
+      catch (InterruptedException e)
+        {
+          // Ignore, we've suspended indefinitely to let all shutdown
+          // hooks complete, and to let any non-zero exits through, because
+          // this is a duplicate call to exit(0).
+        }
   }
 
-  private final static void checkExit (int status)
+  /**
+   * Register a new shutdown hook. This is invoked when the program exits
+   * normally (because all non-daemon threads ended, or because
+   * <code>System.exit</code> was invoked), or when the user terminates
+   * the virtual machine (such as by typing ^C, or logging off). There is
+   * a security check to add hooks,
+   * <code>RuntimePermission("shutdownHooks")<code>.
+   *
+   * <p>The hook must be an initialized, but unstarted Thread. The threads
+   * are run concurrently, and started in an arbitrary order; and user
+   * threads or daemons may still be running. Once shutdown hooks have
+   * started, they must all complete, or else you must use <code>halt</code>,
+   * to actually finish the shutdown sequence. Attempts to modify hooks
+   * after shutdown has started result in IllegalStateExceptions.
+   *
+   * <p>It is imperative that you code shutdown hooks defensively, as you
+   * do not want to deadlock, and have no idea what other hooks will be
+   * running concurrently. It is also a good idea to finish quickly, as the
+   * virtual machine really wants to shut down!
+   *
+   * <p>There are no guarantees that such hooks will run, as there are ways
+   * to forcibly kill a process. But in such a drastic case, shutdown hooks
+   * would do little for you in the first place.
+   *
+   * @param hook an initialized, unstarted Thread
+   * @throws IllegalArgumentException if the hook is already registered or run
+   * @throws IllegalStateException if the virtual machine is already in
+   *         the shutdown sequence
+   * @throws SecurityException if permission is denied
+   * @since 1.3
+   * @see #removeShutdownHook(Thread)
+   * @see #exit(int)
+   * @see #halt(int)
+   */
+  public void addShutdownHook(Thread hook)
   {
-    SecurityManager s = System.getSecurityManager();
-    if (s != null)
-      s.checkExit(status);
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkPermission(new RuntimePermission("shutdownHooks"));
+    if (hook.isAlive() || hook.getThreadGroup() == null)
+      throw new IllegalArgumentException();
+    synchronized (libpath)
+      {
+        if (exitSequence != null)
+          throw new IllegalStateException();
+        if (shutdownHooks == null)
+          shutdownHooks = new HashSet(); // Lazy initialization.
+        if (! shutdownHooks.add(hook))
+          throw new IllegalArgumentException();
+      }
   }
 
-  public native void exit (int status);
-  
-  // Shutdown the runtime without a SecurityManager check. libgcj uses this 
-  // exit function internally.
-  final native void _exit (int status);
+  /**
+   * De-register a shutdown hook. As when you registered it, there is a
+   * security check to remove hooks,
+   * <code>RuntimePermission("shutdownHooks")<code>.
+   *
+   * @param hook the hook to remove
+   * @return true if the hook was successfully removed, false if it was not
+   *         registered in the first place
+   * @throws IllegalStateException if the virtual machine is already in
+   *         the shutdown sequence
+   * @throws SecurityException if permission is denied
+   * @since 1.3
+   * @see #addShutdownHook(Thread)
+   * @see #exit(int)
+   * @see #halt(int)
+   */
+  public boolean removeShutdownHook(Thread hook)
+  {
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkPermission(new RuntimePermission("shutdownHooks"));
+    synchronized (libpath)
+      {
+        if (exitSequence != null)
+          throw new IllegalStateException();
+        if (shutdownHooks != null)
+          return shutdownHooks.remove(hook);
+      }
+    return false;
+  }
 
-  public native long freeMemory ();
-  public native void gc ();
+  /**
+   * Forcibly terminate the virtual machine. This call never returns. It is
+   * much more severe than <code>exit</code>, as it bypasses all shutdown
+   * hooks and initializers. Use caution in calling this! Of course, there is
+   * a security check, <code>checkExit(status)</code>.
+   *
+   * @param status the status to exit with
+   * @throws SecurityException if permission is denied
+   * @since 1.3
+   * @see #exit(int)
+   * @see #addShutdownHook(Thread)
+   */
+  public void halt(int status)
+  {
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkExit(status);
+    exitInternal(status);
+  }
 
-  // Deprecated in 1.1.  We implement what the JCL book says.
-  public InputStream getLocalizedInputStream (InputStream in)
+  /**
+   * Tell the VM to run the finalize() method on every single Object before
+   * it exits.  Note that the JVM may still exit abnormally and not perform
+   * this, so you still don't have a guarantee. And besides that, this is
+   * inherently unsafe in multi-threaded code, as it may result in deadlock
+   * as multiple threads compete to manipulate objects. This value defaults to
+   * <code>false</code>. There is a security check, <code>checkExit(0)</code>.
+   *
+   * @param finalizeOnExit whether to finalize all Objects on exit
+   * @throws SecurityException if permission is denied
+   * @see #exit(int)
+   * @see #gc()
+   * @since 1.1
+   * @deprecated never rely on finalizers to do a clean, thread-safe,
+   *             mop-up from your code
+   */
+  public static void runFinalizersOnExit(boolean finalizeOnExit)
   {
-    return in;
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkExit(0);
+    current.finalizeOnExit = finalizeOnExit;
   }
 
-  // Deprecated in 1.1.  We implement what the JCL book says.
-  public OutputStream getLocalizedOutputStream (OutputStream out)
+  /**
+   * Create a new subprocess with the specified command line. Calls
+   * <code>exec(cmdline, null, null)<code>. A security check is performed,
+   * <code>checkExec</code>.
+   *
+   * @param cmdline the command to call
+   * @return the Process object
+   * @throws SecurityException if permission is denied
+   * @throws IOException if an I/O error occurs
+   * @throws NullPointerException if cmdline is null
+   * @throws IndexOutOfBoundsException if cmdline is ""
+   */
+  public Process exec(String cmdline) throws IOException
   {
-    return out;
+    return exec(cmdline, null, null);
   }
 
-  public static Runtime getRuntime ()
+  /**
+   * Create a new subprocess with the specified command line and environment.
+   * If the environment is null, the process inherits the environment of
+   * this process. Calls <code>exec(cmdline, env, null)</code>. A security
+   * check is performed, <code>checkExec</code>.
+   *
+   * @param cmdline 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 cmdline is null, or env has null entries
+   * @throws IndexOutOfBoundsException if cmdline is ""
+   */
+  public Process exec(String cmdline, String[] env) throws IOException
   {
-    return self;
+    return exec(cmdline, env, null);
   }
 
-  private final void checkLink (String lib)
+  /**
+   * Create a new subprocess with the specified command line, 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. This splits cmdline into an array, using
+   * the default StringTokenizer, then calls
+   * <code>exec(cmdArray, env, dir)</code>. A security check is performed,
+   * <code>checkExec</code>.
+   *
+   * @param cmdline 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 cmdline is null, or env has null entries
+   * @throws IndexOutOfBoundsException if cmdline is ""
+   * @since 1.3
+   */
+  public Process exec(String cmdline, String[] env, File dir)
+    throws IOException
   {
-    if (lib == null)
-      throw new NullPointerException ();
-    SecurityManager s = System.getSecurityManager();
-    if (s != null)
-      s.checkLink(lib);
+    StringTokenizer t = new StringTokenizer(cmdline);
+    String[] cmd = new String[t.countTokens()];
+    for (int i = 0; i < cmd.length; i++)
+      cmd[i] = t.nextToken();
+    return exec(cmd, env, dir);
   }
 
-  private native void _load (String pathname, boolean do_search);
+  /**
+   * Create a new subprocess with the specified command line, already
+   * tokenized. Calls <code>exec(cmd, null, null)</code>. A security check
+   * is performed, <code>checkExec</code>.
+   *
+   * @param cmd the command to call
+   * @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 has null entries
+   * @throws IndexOutOfBoundsException if cmd is length 0
+   */
+  public Process exec(String[] cmd) throws IOException
+  {
+    return exec(cmd, null, null);
+  }
 
-  public void load (String pathname)
+  /**
+   * 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
+   * <code>exec(cmd, env, null)</code>. 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
+   * @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
   {
-    _load (pathname, false);
+    return exec(cmd, env, null);
   }
 
-  public void loadLibrary (String libname)
+  /**
+   * 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
+   * @XXX Ignores dir, for now
+   */
+  public Process exec(String[] cmd, String[] env, File dir)
+    throws IOException
   {
-    _load (libname, true);
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkExec(cmd[0]);
+    if (env == null)
+      env = new String[0];
+    //XXX Should be:    return execInternal(cmd, env, dir);
+    return execInternal(cmd, env);
   }
 
-  // This is a helper function for the ClassLoader which can load
-  // compiled libraries.  Returns true if library (which is just the
-  // base name -- path searching is done by this function) was loaded,
-  // false otherwise.
-  native boolean loadLibraryInternal (String libname);
+  /**
+   * 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 native int 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 native long 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 native long 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 native long maxMemory();
 
-  public native void runFinalization ();
+  /**
+   * 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 native void gc();
 
-  // This method is static in JDK 1.1, but isn't listed as static in
-  // the books.  It is marked as static in the 1.2 docs.
-  public static void runFinalizersOnExit (boolean run)
+  /**
+   * 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 native void 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 native void traceInstructions(boolean 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 native void traceMethodCalls(boolean 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>.
+   *
+   * @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)
   {
-    // The status we pass to the security check is unspecified.
-    checkExit (0);
-    self.finalize_on_exit = run;
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkLink(filename);
+    _load(filename, false);
   }
 
-  public native long totalMemory ();
-  public native void traceInstructions (boolean on);
-  public native void traceMethodCalls (boolean on);
+  /**
+   * 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>.
+   *
+   * @param filename the file 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)
+  {
+    // This is different from the Classpath implementation, but I
+    // believe it is more correct.
+    SecurityManager sm = securityManager; // Be thread-safe!
+    if (sm != null)
+      sm.checkLink(libname);
+    _load(libname, false);
+  }
 
-  // A helper for the constructor.
-  private final native void init ();
+  /**
+   * 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
+   */
+  public InputStream getLocalizedInputStream(InputStream in)
+  {
+    return in;
+  }
 
-  // The sole constructor.
-  private Runtime ()
+  /**
+   * 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
+   */
+  public OutputStream getLocalizedOutputStream(OutputStream out)
   {
-    init ();
+    return out;
   }
 
-  // Private data.
-  private static Runtime self = new Runtime ();
-  // FIXME: for now this can't be static.  If it is, our compiler will
-  // mark it as local, and it will be inaccessible to natRuntime.cc.
-  private boolean finalize_on_exit;
-}
+  /**
+   * Native method that actually shuts down the virtual machine.
+   *
+   * @param status the status to end the process with
+   */
+  native void exitInternal(int status);
+
+  /**
+   * Load a file. If it has already been loaded, do nothing. The name has
+   * already been mapped to a true filename.
+   *
+   * @param filename the file to load
+   * @param do_search True if we should search the load path for the file
+   */
+  native void _load(String filename, boolean do_search);
+
+  /**
+   *This is a helper function for the ClassLoader which can load
+   * compiled libraries.  Returns true if library (which is just the
+   * base name -- path searching is done by this function) was loaded,
+   * false otherwise.
+   */
+  native boolean loadLibraryInternal(String libname);
+
+  /**
+   * A helper for the constructor which does some internal native
+   * initialization.
+   */
+  private native void init ();
+
+  /**
+   * Map a system-independent "short name" to the full file name, and append
+   * it to the path.
+   * XXX This method is being replaced by System.mapLibraryName.
+   *
+   * @param pathname the path
+   * @param libname the short version of the library name
+   * @return the full filename
+   */
+  static native String nativeGetLibname(String pathname, String libname);
+
+  /**
+   * Execute a process. The command line has already been tokenized, and
+   * the environment should contain name=value mappings. If directory is null,
+   * use the current working directory; otherwise start the process in that
+   * directory.
+   * XXX Add directory support.
+   *
+   * @param cmd the non-null command tokens
+   * @param env the non-null environment setup
+   * @param dir the directory to use, may be null
+   * @return the newly created process
+   * @throws NullPointerException if cmd or env have null elements
+   */
+  //  native Process execInternal(String[] cmd, String[] env, File dir);
+  native Process execInternal(String[] cmd, String[] env);
+
+  /**
+   * Get the system properties. This is done here, instead of in System,
+   * because of the bootstrap sequence. Note that the native code should
+   * not try to use the Java I/O classes yet, as they rely on the properties
+   * already existing. The only safe method to use to insert these default
+   * system properties is {@link Properties#setProperty(String, String)}.
+   *
+   * <p>These properties MUST include:
+   * <dl>
+   * <dt>java.version         <dd>Java version number
+   * <dt>java.vendor          <dd>Java vendor specific string
+   * <dt>java.vendor.url      <dd>Java vendor URL
+   * <dt>java.home            <dd>Java installation directory
+   * <dt>java.vm.specification.version <dd>VM Spec version
+   * <dt>java.vm.specification.vendor  <dd>VM Spec vendor
+   * <dt>java.vm.specification.name    <dd>VM Spec name
+   * <dt>java.vm.version      <dd>VM implementation version
+   * <dt>java.vm.vendor       <dd>VM implementation vendor
+   * <dt>java.vm.name         <dd>VM implementation name
+   * <dt>java.specification.version    <dd>Java Runtime Environment version
+   * <dt>java.specification.vendor     <dd>Java Runtime Environment vendor
+   * <dt>java.specification.name       <dd>Java Runtime Environment name
+   * <dt>java.class.version   <dd>Java class version number
+   * <dt>java.class.path      <dd>Java classpath
+   * <dt>java.library.path    <dd>Path for finding Java libraries
+   * <dt>java.io.tmpdir       <dd>Default temp file path
+   * <dt>java.compiler        <dd>Name of JIT to use
+   * <dt>java.ext.dirs        <dd>Java extension path
+   * <dt>os.name              <dd>Operating System Name
+   * <dt>os.arch              <dd>Operating System Architecture
+   * <dt>os.version           <dd>Operating System Version
+   * <dt>file.separator       <dd>File separator ("/" on Unix)
+   * <dt>path.separator       <dd>Path separator (":" on Unix)
+   * <dt>line.separator       <dd>Line separator ("\n" on Unix)
+   * <dt>user.name            <dd>User account name
+   * <dt>user.home            <dd>User home directory
+   * <dt>user.dir             <dd>User's current working directory
+   * </dl>
+   *
+   * @param p the Properties object to insert the system properties into
+   */
+  static native void insertSystemProperties(Properties p);
+} // class Runtime