Memory related : JVM Tool Interface « Development Class « Java
Memory related
/*
* Copyright (c) 1998-2002 Carnegie Mellon University. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY CARNEGIE MELLON UNIVERSITY ``AS IS'' AND
* ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY
* NOR ITS EMPLOYEES BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
public abstract class Mem {
public static long free () {
return Runtime.getRuntime ().freeMemory ();
}
public static long used () {
Runtime r = Runtime.getRuntime ();
return r.totalMemory() - r.freeMemory ();
}
public static long total () {
return Runtime.getRuntime ().totalMemory ();
}
public static String getReport () {
return "Memory: used " + (used()/1000) + "KB, free "
+ (free()/1000) + "KB, total " + (total()/1000) + "KB";
}
public static void gc () {
Runtime r = Runtime.getRuntime ();
r.runFinalization ();
r.gc ();
}
public static void dumpThreadInfo () {
ThreadGroup g = Thread.currentThread().getThreadGroup ();
Thread[] t = new Thread[g.activeCount ()];
g.enumerate (t);
System.err.println ("Active threads in " + g);
for (int i=0; i<t.length; ++i)
System.err.println (t[i]);
}
}
