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1   /*
2    * Copyright (c) 2000, 2008, 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   */
24  
25  package sun.jvm.hotspot.oops;
26  
27  import java.io.*;
28  import java.util.*;
29  
30  public class ObjectHistogram implements HeapVisitor {
31  
32    public ObjectHistogram() { map = new HashMap(); }
33  
34    private HashMap map;
35  
36    public void prologue(long size) {}
37  
38    public boolean doObj(Oop obj) {
39      Klass klass = obj.getKlass();
40      if (!map.containsKey(klass)) map.put(klass, new ObjectHistogramElement(klass));
41      ((ObjectHistogramElement) map.get(klass)).updateWith(obj);
42          return false;
43    }
44  
45    public void epilogue() {}
46  
47    /** Call this after the iteration is complete to obtain the
48        ObjectHistogramElements in descending order of total heap size
49        consumed in the form of a List<ObjectHistogramElement>. */
50    public List getElements() {
51      List list = new ArrayList();
52      list.addAll(map.values());
53      Collections.sort(list, new Comparator() {
54        public int compare(Object o1, Object o2) {
55          return ((ObjectHistogramElement) o1).compare((ObjectHistogramElement) o2);
56        }
57      });
58      return list;
59    }
60  
61    public void print() { printOn(System.out); }
62  
63    public void printOn(PrintStream tty) {
64      List list = getElements();
65      ObjectHistogramElement.titleOn(tty);
66      Iterator iterator = list.listIterator();
67      int num=0;
68      int totalCount=0;
69      int totalSize=0;
70      while (iterator.hasNext()) {
71        ObjectHistogramElement el = (ObjectHistogramElement) iterator.next();
72        num++;
73        totalCount+=el.getCount();
74        totalSize+=el.getSize();
75        tty.print(num + ":" + "\t\t");
76        el.printOn(tty);
77      }
78      tty.println("Total : " + "\t" + totalCount + "\t" + totalSize);
79    }
80  }