HADOOP-3970. Adding the testcase I forgot to add earlier.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/core/trunk@693386 13f79535-47bb-0310-9956-ffa450edef68

src/test/org/apache/hadoop/mapred/TestCounters.java

@@ -0,0 +1,143 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.hadoop.mapred;
+
+import junit.framework.TestCase;
+import java.io.IOException;
+import java.text.ParseException;
+
+import org.apache.hadoop.mapred.Counters.Counter;
+import org.apache.hadoop.mapred.Counters.Group;
+
+/**
+ * TestCounters checks the sanity and recoverability of {@code Counters}
+ */
+public class TestCounters extends TestCase {
+  enum myCounters {TEST1, TEST2};
+  private static final long MAX_VALUE = 10;
+  
+  // Generates enum based counters
+  private Counters getEnumCounters(Enum[] keys) {
+    Counters counters = new Counters();
+    for (Enum key : keys) {
+      for (long i = 0; i < MAX_VALUE; ++i) {
+        counters.incrCounter(key, i);
+      }
+    }
+    return counters;
+  }
+  
+  // Generate string based counters
+  private Counters getEnumCounters(String[] gNames, String[] cNames) {
+    Counters counters = new Counters();
+    for (String gName : gNames) {
+      for (String cName : cNames) {
+        for (long i = 0; i < MAX_VALUE; ++i) {
+          counters.incrCounter(gName, cName, i);
+        }
+      }
+    }
+    return counters;
+  }
+  
+  /**
+   * Test counter recovery
+   */
+  private void testCounter(Counters counter) throws ParseException {
+    String compactEscapedString = counter.makeEscapedCompactString();
+    
+    Counters recoveredCounter = 
+      Counters.fromEscapedCompactString(compactEscapedString);
+    // Check for recovery from string
+    assertTrue("Recovered counter does not match on content", 
+               compareCounters(counter, recoveredCounter));
+    
+  }
+  
+  // Checks for (content) equality of two Counter
+  private boolean compareCounter(Counter c1, Counter c2) {
+    return c1.getName().equals(c2.getName())
+           && c1.getDisplayName().equals(c2.getDisplayName())
+           && c1.getCounter() == c2.getCounter();
+  }
+  
+  // Checks for (content) equality of Groups
+  private boolean compareGroup(Group g1, Group g2) {
+    boolean isEqual = false;
+    if (g1 != null && g2 != null) {
+      if (g1.size() == g2.size()) {
+        isEqual = true;
+        for (String cname : g1.getCounterNames()) {
+          Counter c1 = g1.getCounterForName(cname);
+          Counter c2 = g2.getCounterForName(cname);
+          if (!compareCounter(c1, c2)) {
+            isEqual = false;
+            break;
+          }
+        }
+      }
+    }
+    return isEqual;
+  }
+  
+  // Checks for (content) equality of Counters
+  private boolean compareCounters(Counters c1, Counters c2) {
+    boolean isEqual = false;
+    if (c1 != null && c2 != null) {
+      if (c1.size() == c2.size()) {
+        isEqual = true;
+        for (Group g1 : c1) {
+          Group g2 = c2.getGroup(g1.getName());
+          if (!compareGroup(g1, g2)) {
+            isEqual = false;
+            break;
+          }
+        }
+      }
+    }
+    return isEqual;
+  }
+  
+  public void testCounters() throws IOException {
+    Enum[] keysWithResource = {Task.FileSystemCounter.HDFS_READ, 
+                               Task.Counter.MAP_INPUT_BYTES, 
+                               Task.Counter.MAP_OUTPUT_BYTES};
+    
+    Enum[] keysWithoutResource = {myCounters.TEST1, myCounters.TEST2};
+    
+    String[] groups = {"group1", "group2", "group{}()[]"};
+    String[] counters = {"counter1", "counter2", "counter{}()[]"};
+    
+    try {
+      // I. Check enum counters that have resource bundler
+      testCounter(getEnumCounters(keysWithResource));
+
+      // II. Check enum counters that dont have resource bundler
+      testCounter(getEnumCounters(keysWithoutResource));
+
+      // III. Check string counters
+      testCounter(getEnumCounters(groups, counters));
+    } catch (ParseException pe) {
+      throw new IOException(pe);
+    }
+  }
+  
+  public static void main(String[] args) throws IOException {
+    new TestCounters().testCounters();
+  }
+}