1 /*
   2  * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.graalvm.compiler.debug;
  24 
  25 import com.sun.management.ThreadMXBean;
  26 
  27 /**
  28  * Tracks memory usage within a scope using {@link ThreadMXBean}. This facility should be employed
  29  * using the try-with-resources pattern:
  30  *
  31  * <pre>
  32  * try (DebugMemUseTracker.Closeable a = memUseTracker.start()) {
  33  *     // the code to measure
  34  * }
  35  * </pre>
  36  */
  37 public interface DebugMemUseTracker {
  38 
  39     /**
  40      * Creates a point from which memory usage will be recorded if memory use tracking is
  41      * {@linkplain Debug#isMemUseTrackingEnabled() enabled}.
  42      *
  43      * @return an object that must be closed once the activity has completed to add the memory used
  44      *         since this call to the total for this tracker
  45      */
  46     DebugCloseable start();
  47 
  48     /**
  49      * Gets the current value of this tracker.
  50      */
  51     long getCurrentValue();
  52 }