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<TD><CODE><B><A HREF="../../java/lang/Runtime.html#runFinalization()">runFinalization</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Runs the finalization methods of any objects pending finalization.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>static&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/lang/Runtime.html#runFinalizersOnExit(boolean)">runFinalizersOnExit</A></B>(boolean&nbsp;value)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Deprecated.</B>&nbsp;<I>This method is inherently unsafe.  It may result in
 	    finalizers being called on live objects while other threads are
      concurrently manipulating those objects, resulting in erratic
	    behavior or deadlock.</I></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;long</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/lang/Runtime.html#totalMemory()">totalMemory</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Returns the total amount of memory in the Java Virtual Machine.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/lang/Runtime.html#traceInstructions(boolean)">traceInstructions</A></B>(boolean&nbsp;on)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Enables/Disables tracing of instructions.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../java/lang/Runtime.html#traceMethodCalls(boolean)">traceMethodCalls</A></B>(boolean&nbsp;on)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Enables/Disables tracing of method calls.</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
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<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from class java.lang.<A HREF="../../java/lang/Object.html">Object</A></B></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE><A HREF="../../java/lang/Object.html#clone()">clone</A>, <A HREF="../../java/lang/Object.html#equals(java.lang.Object)">equals</A>, <A HREF="../../java/lang/Object.html#finalize()">finalize</A>, <A HREF="../../java/lang/Object.html#getClass()">getClass</A>, <A HREF="../../java/lang/Object.html#hashCode()">hashCode</A>, <A HREF="../../java/lang/Object.html#notify()">notify</A>, <A HREF="../../java/lang/Object.html#notifyAll()">notifyAll</A>, <A HREF="../../java/lang/Object.html#toString()">toString</A>, <A HREF="../../java/lang/Object.html#wait()">wait</A>, <A HREF="../../java/lang/Object.html#wait(long)">wait</A>, <A HREF="../../java/lang/Object.html#wait(long, int)">wait</A></CODE></TD>
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<B>Method Detail</B></FONT></TD>
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<A NAME="getRuntime()"><!-- --></A><H3>
getRuntime</H3>
<PRE>
public static <A HREF="../../java/lang/Runtime.html">Runtime</A> <B>getRuntime</B>()</PRE>
<DL>
<DD>Returns the runtime object associated with the current Java application.
 Most of the methods of class <code>Runtime</code> are instance 
 methods and must be invoked with respect to the current runtime object.<DD><DL>
<DT><B>Returns:</B><DD>the <code>Runtime</code> object associated with the current
          Java application.</DL>
</DD>
</DL>
<HR>

<A NAME="exit(int)"><!-- --></A><H3>
exit</H3>
<PRE>
public void <B>exit</B>(int&nbsp;status)</PRE>
<DL>
<DD>Terminates the currently running Java virtual machine by initiating its
 shutdown sequence.  This method never returns normally.  The argument
 serves as a status code; by convention, a nonzero status code indicates
 abnormal termination.

 <p> The virtual machine's shutdown sequence constists of two phases.  In
 the first phase all registered <A HREF="../../java/lang/Runtime.html#addShutdownHook(java.lang.Thread)"><CODE>shutdown hooks</CODE></A>,
 if any, are started in some unspecified order and allowed to run
 concurrently until they finish.  In the second phase all uninvoked
 finalizers are run if <A HREF="../../java/lang/Runtime.html#runFinalizersOnExit(boolean)"><CODE>finalization-on-exit</CODE></A>
 has been enabled.  Once this is done the virtual machine <A HREF="../../java/lang/Runtime.html#halt(int)"><CODE>halts</CODE></A>.

 <p> If this method is invoked after the virtual machine has begun its
 shutdown sequence then if shutdown hooks are being run this method will
 block indefinitely.  If shutdown hooks have already been run and on-exit
 finalization has been enabled then this method halts the virtual machine
 with the given status code if the status is nonzero; otherwise, it
 blocks indefinitely.

 <p> The <tt><A HREF="../../java/lang/System.html#exit(int)"><CODE>System.exit</CODE></A></tt> method is the
 conventional and convenient means of invoking this method. <p><DD><DL>
<DT><B>Parameters:</B><DD><CODE>status</CODE> - Termination status.  By convention, a nonzero status code
         indicates abnormal termination.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - If a security manager is present and its <tt><A HREF="../../java/lang/SecurityManager.html#checkExit(int)"><CODE>checkExit</CODE></A></tt> method does not permit
         exiting with the specified status<DT><B>See Also: </B><DD><A HREF="../../java/lang/SecurityException.html"><CODE>SecurityException</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExit(int)"><CODE>SecurityManager.checkExit(int)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#addShutdownHook(java.lang.Thread)"><CODE>addShutdownHook(java.lang.Thread)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#removeShutdownHook(java.lang.Thread)"><CODE>removeShutdownHook(java.lang.Thread)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#runFinalizersOnExit(boolean)"><CODE>runFinalizersOnExit(boolean)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#halt(int)"><CODE>halt(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="addShutdownHook(java.lang.Thread)"><!-- --></A><H3>
addShutdownHook</H3>
<PRE>
public void <B>addShutdownHook</B>(<A HREF="../../java/lang/Thread.html">Thread</A>&nbsp;hook)</PRE>
<DL>
<DD>Registers a new virtual-machine shutdown hook.

 <p> The Java virtual machine <i>shuts down</i> in response to two kinds
 of events:

   <ul>

   <p> <li> The program <i>exits</i> normally, when the last non-daemon
   thread exits or when the <tt><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit</CODE></A></tt> (equivalently,
   <tt><A HREF="../../java/lang/System.html#exit(int)"><CODE>System.exit</CODE></A></tt>) method is invoked, or

   <p> <li> The virtual machine is <i>terminated</i> in response to a
   user interrupt, such as typing <tt>^C</tt>, or a system-wide event,
   such as user logoff or system shutdown.

   </ul>

 <p> A <i>shutdown hook</i> is simply an initialized but unstarted
 thread.  When the virtual machine begins its shutdown sequence it will
 start all registered shutdown hooks in some unspecified order and let
 them run concurrently.  When all the hooks have finished it will then
 run all uninvoked finalizers if finalization-on-exit has been enabled.
 Finally, the virtual machine will halt.  Note that daemon threads will
 continue to run during the shutdown sequence, as will non-daemon threads
 if shutdown was initiated by invoking the <tt><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit</CODE></A></tt>
 method.

 <p> Once the shutdown sequence has begun it can be stopped only by
 invoking the <tt><A HREF="../../java/lang/Runtime.html#halt(int)"><CODE>halt</CODE></A></tt> method, which forcibly
 terminates the virtual machine.

 <p> Once the shutdown sequence has begun it is impossible to register a
 new shutdown hook or de-register a previously-registered hook.
 Attempting either of these operations will cause an
 <tt><A HREF="../../java/lang/IllegalStateException.html"><CODE>IllegalStateException</CODE></A></tt> to be thrown.

 <p> Shutdown hooks run at a delicate time in the life cycle of a virtual
 machine and should therefore be coded defensively.  They should, in
 particular, be written to be thread-safe and to avoid deadlocks insofar
 as possible.  They should also not rely blindly upon services that may
 have registered their own shutdown hooks and therefore may themselves in
 the process of shutting down.

 <p> Shutdown hooks should also finish their work quickly.  When a
 program invokes <tt><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit</CODE></A></tt> the expectation is
 that the virtual machine will promptly shut down and exit.  When the
 virtual machine is terminated due to user logoff or system shutdown the
 underlying operating system may only allow a fixed amount of time in
 which to shut down and exit.  It is therefore inadvisable to attempt any
 user interaction or to perform a long-running computation in a shutdown
 hook.

 <p> Uncaught exceptions are handled in shutdown hooks just as in any
 other thread, by invoking the <tt><A HREF="../../java/lang/ThreadGroup.html#uncaughtException(java.lang.Thread, java.lang.Throwable)"><CODE>uncaughtException</CODE></A></tt> method of the thread's <tt><A HREF="../../java/lang/ThreadGroup.html"><CODE>ThreadGroup</CODE></A></tt> object.  The default implementation of this method
 prints the exception's stack trace to <tt><A HREF="../../java/lang/System.html#err"><CODE>System.err</CODE></A></tt> and
 terminates the thread; it does not cause the virtual machine to exit or
 halt.

 <p> In rare circumstances the virtual machine may <i>abort</i>, that is,
 stop running without shutting down cleanly.  This occurs when the
 virtual machine is terminated externally, for example with the
 <tt>SIGKILL</tt> signal on Unix or the <tt>TerminateProcess</tt> call on
 Win32.  The virtual machine may also abort if a native method goes awry
 by, for example, corrupting internal data structures or attempting to
 access nonexistent memory.  If the virtual machine aborts then no
 guarantee can be made about whether or not any shutdown hooks will be
 run. <p><DD><DL>
<DT><B>Parameters:</B><DD><CODE>hook</CODE> - An initialized but unstarted <tt><A HREF="../../java/lang/Thread.html"><CODE>Thread</CODE></A></tt> object<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/IllegalArgumentException.html">IllegalArgumentException</A></CODE> - If the specified hook has already been registered,
          or if it can be determined that the hook is already running or
          has already been run<DD><CODE><A HREF="../../java/lang/IllegalStateException.html">IllegalStateException</A></CODE> - If the virtual machine is already in the process
          of shutting down<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - If a security manager is present and it denies
          <tt><A HREF="../../java/lang/RuntimePermission.html"><CODE>RuntimePermission</CODE></A>("shutdownHooks")</tt><DT><B>Since: </B><DD>1.3</DD>
<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#removeShutdownHook(java.lang.Thread)"><CODE>removeShutdownHook(java.lang.Thread)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#halt(int)"><CODE>halt(int)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="removeShutdownHook(java.lang.Thread)"><!-- --></A><H3>
removeShutdownHook</H3>
<PRE>
public boolean <B>removeShutdownHook</B>(<A HREF="../../java/lang/Thread.html">Thread</A>&nbsp;hook)</PRE>
<DL>
<DD>De-registers a previously-registered virtual-machine shutdown hook. <p><DD><DL>
<DT><B>Parameters:</B><DD><CODE>hook</CODE> - the hook to remove<DT><B>Returns:</B><DD><tt>true</tt> if the specified hook had previously been
 registered and was successfully de-registered, <tt>false</tt>
 otherwise.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/IllegalStateException.html">IllegalStateException</A></CODE> - If the virtual machine is already in the process of shutting
          down<DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - If a security manager is present and it denies
          <tt><A HREF="../../java/lang/RuntimePermission.html"><CODE>RuntimePermission</CODE></A>("shutdownHooks")</tt><DT><B>Since: </B><DD>1.3</DD>
<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#addShutdownHook(java.lang.Thread)"><CODE>addShutdownHook(java.lang.Thread)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="halt(int)"><!-- --></A><H3>
halt</H3>
<PRE>
public void <B>halt</B>(int&nbsp;status)</PRE>
<DL>
<DD>Forcibly terminates the currently running Java virtual machine.  This
 method never returns normally.

 <p> This method should be used with extreme caution.  Unlike the
 <tt><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit</CODE></A></tt> method, this method does not cause shutdown
 hooks to be started and does not run uninvoked finalizers if
 finalization-on-exit has been enabled.  If the shutdown sequence has
 already been initiated then this method does not wait for any running
 shutdown hooks or finalizers to finish their work. <p><DD><DL>
<DT><B>Parameters:</B><DD><CODE>status</CODE> - Termination status.  By convention, a nonzero status code
         indicates abnormal termination.  If the <tt><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit</CODE></A></tt> (equivalently, <tt><A HREF="../../java/lang/System.html#exit(int)"><CODE>System.exit</CODE></A></tt>) method has already been invoked then this
         status code will override the status code passed to that method.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - If a security manager is present and its <tt><A HREF="../../java/lang/SecurityManager.html#checkExit(int)"><CODE>checkExit</CODE></A></tt> method does not permit
         an exit with the specified status<DT><B>Since: </B><DD>1.3</DD>
<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit(int)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#addShutdownHook(java.lang.Thread)"><CODE>addShutdownHook(java.lang.Thread)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#removeShutdownHook(java.lang.Thread)"><CODE>removeShutdownHook(java.lang.Thread)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="runFinalizersOnExit(boolean)"><!-- --></A><H3>
runFinalizersOnExit</H3>
<PRE>
public static void <B>runFinalizersOnExit</B>(boolean&nbsp;value)</PRE>
<DL>
<DD><B>Deprecated.</B>&nbsp;<I>This method is inherently unsafe.  It may result in
 	    finalizers being called on live objects while other threads are
      concurrently manipulating those objects, resulting in erratic
	    behavior or deadlock.</I>