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.List;
  27 
  28 import org.graalvm.compiler.debug.DebugHistogram;
  29 import org.graalvm.compiler.debug.DebugHistogram.CountedValue;
  30 import org.graalvm.compiler.debug.DebugHistogram.Printer;
  31 
  32 /**
  33  * Renders a histogram as an R script to a given print stream. The R script emitted for a histogram
  34  * is a simple set of statements for defining a vector of named objects.
  35  */
  36 public class DebugHistogramRPrinter implements Printer {
  37 
  38     private PrintStream os;
  39     private int limit;
  40 
  41     public DebugHistogramRPrinter(PrintStream os) {
  42         this(os, Integer.MAX_VALUE);
  43     }
  44 
  45     /**
  46      * @param os where to print
  47      * @param limit limits printing to the {@code limit} most frequent values
  48      */
  49     public DebugHistogramRPrinter(PrintStream os, int limit) {
  50         this.os = os;
  51         this.limit = limit;
  52     }
  53 
  54     @Override
  55     public void print(DebugHistogram histogram) {
  56         List<CountedValue> list = histogram.getValues();
  57         if (list.isEmpty()) {
  58             return;
  59         }
  60 
  61         String var = histogram.getName().replace('-', '.').replace(' ', '_');
  62         os.print(var + " <- c(");
  63         for (int i = 0; i < list.size() && i < limit; ++i) {
  64             CountedValue cv = list.get(i);
  65             if (i != 0) {
  66                 os.print(", ");
  67             }
  68             os.print(cv.getCount());
  69         }
  70         os.println(");");
  71 
  72         os.print("names(" + var + ") <- c(");
  73         for (int i = 0; i < list.size() && i < limit; ++i) {
  74             CountedValue cv = list.get(i);
  75             if (i != 0) {
  76                 os.print(", ");
  77             }
  78             os.print("\"" + cv.getValue() + "\"");
  79         }
  80         os.println(");");
  81     }
  82 }