HADOOP-9349. Confusing output when running hadoop version from one hadoop installation when HADOOP_HOME points to another. (sandyr via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1451450 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -507,6 +507,9 @@ Release 1.2.0 - unreleased
 
     MAPREDUCE-5035. Update MR1 memory configuration docs. (tomwhite)
 
+    HADOOP-9349. Confusing output when running hadoop version from one hadoop 
+    installation when HADOOP_HOME points to another. (sandyr via tucu)
+
 Release 1.1.2 - Unreleased
 
   INCOMPATIBLE CHANGES

src/core/org/apache/hadoop/util/ClassUtil.java

@@ -0,0 +1,60 @@
+/*
+ * 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.util;
+
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLDecoder;
+import java.util.Enumeration;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+@InterfaceAudience.Private
+public class ClassUtil {
+  /** 
+   * Find a jar that contains a class of the same name, if any.
+   * It will return a jar file, even if that is not the first thing
+   * on the class path that has a class with the same name.
+   * 
+   * @param clazz the class to find.
+   * @return a jar file that contains the class, or null.
+   * @throws IOException
+   */
+  public static String findContainingJar(Class clazz) {
+    ClassLoader loader = clazz.getClassLoader();
+    String classFile = clazz.getName().replaceAll("\\.", "/") + ".class";
+    try {
+      for (Enumeration itr = loader.getResources(classFile);
+          itr.hasMoreElements();) {
+        URL url = (URL) itr.nextElement();
+        if ("jar".equals(url.getProtocol())) {
+          String toReturn = url.getPath();
+          if (toReturn.startsWith("file:")) {
+            toReturn = toReturn.substring("file:".length());
+          }
+          toReturn = URLDecoder.decode(toReturn, "UTF-8");
+          return toReturn.replaceAll("!.*$", "");
+        }
+      }
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+    return null;
+  }
+}

src/core/org/apache/hadoop/util/VersionInfo.java

@@ -18,6 +18,11 @@
 
 package org.apache.hadoop.util;
 
+import java.io.IOException;
+import java.net.URL;
+import java.net.URLDecoder;
+import java.util.Enumeration;
+
 import org.apache.hadoop.HadoopVersionAnnotation;
 
 /**
@@ -104,6 +109,7 @@ public class VersionInfo {
     System.out.println("Subversion " + getUrl() + " -r " + getRevision());
     System.out.println("Compiled by " + getUser() + " on " + getDate());
     System.out.println("From source with checksum " + getSrcChecksum());
-
+    System.out.println("This command was run using " + 
+        ClassUtil.findContainingJar(VersionInfo.class));
   }
 }

src/mapred/org/apache/hadoop/mapred/JobConf.java

@@ -42,6 +42,7 @@ import org.apache.hadoop.mapred.lib.HashPartitioner;
 import org.apache.hadoop.mapred.lib.KeyFieldBasedComparator;
 import org.apache.hadoop.mapred.lib.KeyFieldBasedPartitioner;
 import org.apache.hadoop.security.Credentials;
+import org.apache.hadoop.util.ClassUtil;
 import org.apache.hadoop.util.ReflectionUtils;
 import org.apache.hadoop.util.Tool;
 
@@ -436,7 +437,7 @@ public class JobConf extends Configuration {
    * @param cls the example class.
    */
   public void setJarByClass(Class cls) {
-    String jar = findContainingJar(cls);
+    String jar = ClassUtil.findContainingJar(cls);
     if (jar != null) {
       setJar(jar);
     }   
@@ -1788,38 +1789,6 @@ public class JobConf extends Configuration {
     return 
     (int)(Math.ceil((float)getMemoryForReduceTask() / (float)slotSizePerReduce));
   }
-  
-  /** 
-   * Find a jar that contains a class of the same name, if any.
-   * It will return a jar file, even if that is not the first thing
-   * on the class path that has a class with the same name.
-   * 
-   * @param my_class the class to find.
-   * @return a jar file that contains the class, or null.
-   * @throws IOException
-   */
-  private static String findContainingJar(Class my_class) {
-    ClassLoader loader = my_class.getClassLoader();
-    String class_file = my_class.getName().replaceAll("\\.", "/") + ".class";
-    try {
-      for(Enumeration itr = loader.getResources(class_file);
-          itr.hasMoreElements();) {
-        URL url = (URL) itr.nextElement();
-        if ("jar".equals(url.getProtocol())) {
-          String toReturn = url.getPath();
-          if (toReturn.startsWith("file:")) {
-            toReturn = toReturn.substring("file:".length());
-          }
-          toReturn = URLDecoder.decode(toReturn, "UTF-8");
-          return toReturn.replaceAll("!.*$", "");
-        }
-      }
-    } catch (IOException e) {
-      throw new RuntimeException(e);
-    }
-    return null;
-  }
-
 
   /**
    * Get the memory required to run a task of this job, in bytes. See

src/test/org/apache/hadoop/util/TestClassUtil.java

@@ -0,0 +1,40 @@
+/*
+ * 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.util;
+
+import java.io.File;
+
+import junit.framework.Assert;
+
+import org.apache.log4j.Logger;
+import org.junit.Test;
+
+public class TestClassUtil {
+  @Test
+  public void testFindContainingJar() {
+    String containingJar = ClassUtil.findContainingJar(Logger.class);
+    Assert.assertNotNull("Containing jar not found for Logger", 
+        containingJar);
+    File jarFile = new File(containingJar);
+    Assert.assertTrue("Containing jar does not exist on file system", 
+        jarFile.exists());
+    Assert.assertTrue("Incorrect jar file" + containingJar,  
+        jarFile.getName().matches("log4j.+[.]jar"));
+  }
+}