1 /*
   2  * Copyright (c) 2015, 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.java2d.marlin.stats;
  27 
  28 import java.util.Arrays;
  29 
  30 /**
  31  * Generic histogram based on long statistics
  32  */
  33 public final class Histogram extends StatLong {
  34 
  35     static final int BUCKET = 2;
  36     static final int MAX = 20;
  37     static final int LAST = MAX - 1;
  38     static final int[] STEPS = new int[MAX];
  39 
  40     static {
  41             STEPS[0] = 0;
  42             STEPS[1] = 1;
  43 
  44             for (int i = 2; i < MAX; i++) {
  45                 STEPS[i] = STEPS[i - 1] * BUCKET;
  46             }
  47 //            System.out.println("Histogram.STEPS = " + Arrays.toString(STEPS));
  48     }
  49 
  50     static int bucket(int val) {
  51         for (int i = 1; i < MAX; i++) {
  52             if (val < STEPS[i]) {
  53                 return i - 1;
  54             }
  55         }
  56         return LAST;
  57     }
  58 
  59     private final StatLong[] stats = new StatLong[MAX];
  60 
  61     public Histogram(final String name) {
  62         super(name);
  63         for (int i = 0; i < MAX; i++) {
  64             stats[i] = new StatLong(String.format("%5s .. %5s", STEPS[i],
  65                                     ((i + 1 < MAX) ? STEPS[i + 1] : "~")));
  66         }
  67     }
  68 
  69     @Override
  70     public void reset() {
  71         super.reset();
  72         for (int i = 0; i < MAX; i++) {
  73             stats[i].reset();
  74         }
  75     }
  76 
  77     @Override
  78     public void add(int val) {
  79         super.add(val);
  80         stats[bucket(val)].add(val);
  81     }
  82 
  83     @Override
  84     public void add(long val) {
  85         add((int) val);
  86     }
  87 
  88     @Override
  89     public String toString() {
  90         final StringBuilder sb = new StringBuilder(2048);
  91         super.toString(sb).append(" { ");
  92 
  93         for (int i = 0; i < MAX; i++) {
  94             if (stats[i].count != 0l) {
  95                 sb.append("\n        ").append(stats[i].toString());
  96             }
  97         }
  98 
  99         return sb.append(" }").toString();
 100     }
 101 }
 102