1 /* 2 * Copyright (c) 2013, 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.internal; 24 25 import java.io.PrintStream; 26 import java.util.Arrays; 27 import java.util.List; 28 29 import org.graalvm.compiler.debug.DebugHistogram; 30 import org.graalvm.compiler.debug.DebugHistogram.CountedValue; 31 import org.graalvm.compiler.debug.DebugHistogram.Printer; 32 33 /** 34 * Renders a textual representation of a histogram to a given print stream. 35 */ 36 public class DebugHistogramAsciiPrinter implements Printer { 37 38 public static final int NumberSize = 10; 39 public static final int DefaultNameSize = 50; 40 public static final int DefaultBarSize = 100; 41 public static final int DefaultScale = 1; 42 43 private final PrintStream os; 44 private final int limit; 45 private final int nameSize; 46 private final int barSize; 47 private final int scale; 48 49 public DebugHistogramAsciiPrinter(PrintStream os) { 50 this(os, Integer.MAX_VALUE, DefaultNameSize, DefaultBarSize, DefaultScale); 51 } 52 53 /** 54 * @param os where to print 55 * @param limit limits printing to the {@code limit} most frequent values 56 * @param nameSize the width of the value names column 57 * @param barSize the width of the value frequency column 58 * @param scale a factor by which every result is divided 59 */ 60 public DebugHistogramAsciiPrinter(PrintStream os, int limit, int nameSize, int barSize, int scale) { 61 this.os = os; 62 this.limit = limit; 63 this.nameSize = nameSize; 64 this.barSize = barSize; 65 this.scale = scale; 66 } 67 68 @Override 69 public void print(DebugHistogram histogram) { 70 List<CountedValue> list = histogram.getValues(); 71 if (list.isEmpty()) { 72 os.printf("%s is empty.%n", histogram.getName()); 73 return; 74 } 75 76 // Sum up the total number of elements. 77 long total = list.stream().mapToLong(CountedValue::getCount).sum(); 78 79 // Print header. 80 os.printf("%s has %d unique elements and %d total elements:%n", histogram.getName(), list.size(), total / scale); 81 82 long max = list.get(0).getCount() / scale; 83 final int lineSize = nameSize + NumberSize + barSize + 10; 84 printLine(os, '-', lineSize); 85 String formatString = "| %-" + nameSize + "s | %-" + NumberSize + "d | %-" + barSize + "s |\n"; 86 for (int i = 0; i < list.size() && i < limit; ++i) { 87 CountedValue cv = list.get(i); 88 long value = cv.getCount() / scale; 89 char[] bar = new char[(int) (((double) value / (double) max) * barSize)]; 90 Arrays.fill(bar, '='); 91 String objectString = String.valueOf(cv.getValue()); 92 if (objectString.length() > nameSize) { 93 objectString = objectString.substring(0, nameSize - 3) + "..."; 94 } 95 os.printf(formatString, objectString, value, new String(bar)); 96 } 97 printLine(os, '-', lineSize); 98 } 99 100 private static void printLine(PrintStream printStream, char c, int lineSize) { 101 char[] charArr = new char[lineSize]; 102 Arrays.fill(charArr, c); 103 printStream.printf("%s%n", new String(charArr)); 104 } 105 }