# HG changeset patch
# User Doug Simon <doug.simon@oracle.com>
# Date 1378740863 -7200
# Node ID a771cc1f10f5f3ce979f235129bd3b99a5325a7c
# Parent  63b4694d3627cfb310e8eee66908553a5fac6f0c
added DebugHistogram printer that emits R statements to instantiate a vector of named values corresponding to the histogram

diff -r 63b4694d3627 -r a771cc1f10f5 graal/com.oracle.graal.debug.test/src/com/oracle/graal/debug/test/DebugHistogramTest.java
--- a/graal/com.oracle.graal.debug.test/src/com/oracle/graal/debug/test/DebugHistogramTest.java	Mon Sep 09 13:57:53 2013 +0200
+++ b/graal/com.oracle.graal.debug.test/src/com/oracle/graal/debug/test/DebugHistogramTest.java	Mon Sep 09 17:34:23 2013 +0200
@@ -35,8 +35,13 @@
     public void testEmptyHistogram() {
         DebugHistogram histogram = Debug.createHistogram("TestHistogram");
         ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+
         new DebugHistogramAsciiPrinter(new PrintStream(outputStream)).print(histogram);
         Assert.assertEquals("TestHistogram is empty.\n", outputStream.toString());
+
+        outputStream.reset();
+        new DebugHistogramRPrinter(new PrintStream(outputStream)).print(histogram);
+        Assert.assertEquals("", outputStream.toString());
     }
 
     @Test
@@ -47,17 +52,26 @@
         histogram.add(new Integer(1));
         new DebugHistogramAsciiPrinter(new PrintStream(outputStream)).print(histogram);
         String[] lines = outputStream.toString().split("\n");
-        Assert.assertEquals(4, lines.length);
-        Assert.assertEquals("TestHistogram has 1 unique elements and 2 total elements:", lines[0]);
-        Assert.assertEquals(
-                        "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
-                        lines[1]);
-        Assert.assertEquals(
-                        "| 1                                                  | 2          | ==================================================================================================== |",
-                        lines[2]);
-        Assert.assertEquals(
-                        "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
-                        lines[3]);
+        // @formatter:off
+        String[] expected = {
+            "TestHistogram has 1 unique elements and 2 total elements:",
+            "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
+            "| 1                                                  | 2          | ==================================================================================================== |",
+            "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------"
+        };
+        // @formatter:on
+        Assert.assertArrayEquals(expected, lines);
+
+        outputStream.reset();
+        new DebugHistogramRPrinter(new PrintStream(outputStream)).print(histogram);
+        lines = outputStream.toString().split("\n");
+        // @formatter:off
+        expected = new String[] {
+            "TestHistogram <- c(2);",
+            "names(TestHistogram) <- c(\"1\");"
+        };
+        // @formatter:on
+        Assert.assertArrayEquals(expected, lines);
     }
 
     @Test
@@ -69,20 +83,27 @@
         histogram.add(new Integer(2));
         new DebugHistogramAsciiPrinter(new PrintStream(outputStream)).print(histogram);
         String[] lines = outputStream.toString().split("\n");
-        Assert.assertEquals(5, lines.length);
-        Assert.assertEquals("TestHistogram has 2 unique elements and 3 total elements:", lines[0]);
-        Assert.assertEquals(
-                        "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
-                        lines[1]);
-        Assert.assertEquals(
-                        "| 2                                                  | 2          | ==================================================================================================== |",
-                        lines[2]);
-        Assert.assertEquals(
-                        "| 1                                                  | 1          | ==================================================                                                   |",
-                        lines[3]);
-        Assert.assertEquals(
-                        "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
-                        lines[4]);
+        // @formatter:off
+        String[] expected = new String[] {
+            "TestHistogram has 2 unique elements and 3 total elements:",
+            "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------",
+            "| 2                                                  | 2          | ==================================================================================================== |",
+            "| 1                                                  | 1          | ==================================================                                                   |",
+            "--------------------------------------------------------------------------------------------------------------------------------------------------------------------------"
+        };
+        // @formatter:on
+        Assert.assertArrayEquals(expected, lines);
+
+        outputStream.reset();
+        new DebugHistogramRPrinter(new PrintStream(outputStream)).print(histogram);
+        lines = outputStream.toString().split("\n");
+        // @formatter:off
+        expected = new String[] {
+            "TestHistogram <- c(2, 1);",
+            "names(TestHistogram) <- c(\"2\", \"1\");"
+        };
+        // @formatter:on
+        Assert.assertArrayEquals(expected, lines);
     }
 
     @Test
diff -r 63b4694d3627 -r a771cc1f10f5 graal/com.oracle.graal.debug/src/com/oracle/graal/debug/internal/DebugHistogramRPrinter.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.graal.debug/src/com/oracle/graal/debug/internal/DebugHistogramRPrinter.java	Mon Sep 09 17:34:23 2013 +0200
@@ -0,0 +1,81 @@
+/*
+ * 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 com.oracle.graal.debug.internal;
+
+import java.io.*;
+import java.util.*;
+
+import com.oracle.graal.debug.*;
+import com.oracle.graal.debug.DebugHistogram.CountedValue;
+import com.oracle.graal.debug.DebugHistogram.Printer;
+
+/**
+ * Renders a histogram as an R script to a given print stream. The R script emitted for a histogram
+ * is a simple set of statements for defining a vector of named objects.
+ */
+public class DebugHistogramRPrinter implements Printer {
+
+    private PrintStream os;
+    private int limit;
+
+    public DebugHistogramRPrinter(PrintStream os) {
+        this(os, Integer.MAX_VALUE);
+    }
+
+    /**
+     * @param os where to print
+     * @param limit limits printing to the {@code limit} most frequent values
+     */
+    public DebugHistogramRPrinter(PrintStream os, int limit) {
+        this.os = os;
+        this.limit = limit;
+    }
+
+    public void print(DebugHistogram histogram) {
+        List<CountedValue> list = histogram.getValues();
+        if (list.isEmpty()) {
+            return;
+        }
+
+        String var = histogram.getName().replace('-', '.').replace(' ', '_');
+        os.print(var + " <- c(");
+        for (int i = 0; i < list.size() && i < limit; ++i) {
+            CountedValue cv = list.get(i);
+            if (i != 0) {
+                os.print(", ");
+            }
+            os.print(cv.getCount());
+        }
+        os.println(");");
+
+        os.print("names(" + var + ") <- c(");
+        for (int i = 0; i < list.size() && i < limit; ++i) {
+            CountedValue cv = list.get(i);
+            if (i != 0) {
+                os.print(", ");
+            }
+            os.print("\"" + cv.getValue() + "\"");
+        }
+        os.println(");");
+    }
+}