--- /dev/null 2016-05-31 09:42:47.975716356 -0700 +++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.debug/src/org/graalvm/compiler/debug/internal/DebugHistogramAsciiPrinter.java 2016-12-09 00:48:16.842118397 -0800 @@ -0,0 +1,105 @@ +/* + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +package org.graalvm.compiler.debug.internal; + +import java.io.PrintStream; +import java.util.Arrays; +import java.util.List; + +import org.graalvm.compiler.debug.DebugHistogram; +import org.graalvm.compiler.debug.DebugHistogram.CountedValue; +import org.graalvm.compiler.debug.DebugHistogram.Printer; + +/** + * Renders a textual representation of a histogram to a given print stream. + */ +public class DebugHistogramAsciiPrinter implements Printer { + + public static final int NumberSize = 10; + public static final int DefaultNameSize = 50; + public static final int DefaultBarSize = 100; + public static final int DefaultScale = 1; + + private final PrintStream os; + private final int limit; + private final int nameSize; + private final int barSize; + private final int scale; + + public DebugHistogramAsciiPrinter(PrintStream os) { + this(os, Integer.MAX_VALUE, DefaultNameSize, DefaultBarSize, DefaultScale); + } + + /** + * @param os where to print + * @param limit limits printing to the {@code limit} most frequent values + * @param nameSize the width of the value names column + * @param barSize the width of the value frequency column + * @param scale a factor by which every result is divided + */ + public DebugHistogramAsciiPrinter(PrintStream os, int limit, int nameSize, int barSize, int scale) { + this.os = os; + this.limit = limit; + this.nameSize = nameSize; + this.barSize = barSize; + this.scale = scale; + } + + @Override + public void print(DebugHistogram histogram) { + List list = histogram.getValues(); + if (list.isEmpty()) { + os.printf("%s is empty.%n", histogram.getName()); + return; + } + + // Sum up the total number of elements. + long total = list.stream().mapToLong(CountedValue::getCount).sum(); + + // Print header. + os.printf("%s has %d unique elements and %d total elements:%n", histogram.getName(), list.size(), total / scale); + + long max = list.get(0).getCount() / scale; + final int lineSize = nameSize + NumberSize + barSize + 10; + printLine(os, '-', lineSize); + String formatString = "| %-" + nameSize + "s | %-" + NumberSize + "d | %-" + barSize + "s |\n"; + for (int i = 0; i < list.size() && i < limit; ++i) { + CountedValue cv = list.get(i); + long value = cv.getCount() / scale; + char[] bar = new char[(int) (((double) value / (double) max) * barSize)]; + Arrays.fill(bar, '='); + String objectString = String.valueOf(cv.getValue()); + if (objectString.length() > nameSize) { + objectString = objectString.substring(0, nameSize - 3) + "..."; + } + os.printf(formatString, objectString, value, new String(bar)); + } + printLine(os, '-', lineSize); + } + + private static void printLine(PrintStream printStream, char c, int lineSize) { + char[] charArr = new char[lineSize]; + Arrays.fill(charArr, c); + printStream.printf("%s%n", new String(charArr)); + } +}