Java tutorial
/* * 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]); } }