HADOOP-7993. Hadoop ignores old-style config options for enabling compressed output. (Anupam Seth via mahadev) - Merging r1236506 from trunk.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1236507 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -167,6 +167,9 @@ Release 0.23.1 - Unreleased
    HADOOP-7997. SequenceFile.createWriter(...createParent...) no
    longer works on existing file. (Gregory Chanan via eli)
 
+   HADOOP-7993. Hadoop ignores old-style config options for enabling compressed 
+   output. (Anupam Seth via mahadev)
+
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/conf/Configuration.java

@@ -345,7 +345,17 @@ public class Configuration implements Iterable<Map.Entry<String,String>>,
     }
     return name;
   }
-  
+ 
+  private void handleDeprecation() {
+    LOG.debug("Handling deprecation for all properties in config...");
+    Set<Object> keys = new HashSet<Object>();
+    keys.addAll(getProps().keySet());
+    for (Object item: keys) {
+      LOG.debug("Handling deprecation for " + (String)item);
+      handleDeprecation((String)item);
+    }
+  }
+ 
   static{
     //print deprecation warning if hadoop-site.xml is found in classpath
     ClassLoader cL = Thread.currentThread().getContextClassLoader();
@@ -1665,7 +1675,7 @@ public class Configuration implements Iterable<Map.Entry<String,String>>,
     Element conf = doc.createElement("configuration");
     doc.appendChild(conf);
     conf.appendChild(doc.createTextNode("\n"));
-    getProps(); // ensure properties is set
+    handleDeprecation(); //ensure properties is set and deprecation is handled
     for (Enumeration e = properties.keys(); e.hasMoreElements();) {
       String name = (String)e.nextElement();
       Object object = properties.get(name);

hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/conf/TestDeprecatedKeys.java

@@ -18,6 +18,8 @@
 
 package org.apache.hadoop.conf;
 
+import java.io.ByteArrayOutputStream;
+
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
 
@@ -32,4 +34,22 @@ public class TestDeprecatedKeys extends TestCase {
     String scriptFile = conf.get(CommonConfigurationKeys.NET_TOPOLOGY_SCRIPT_FILE_NAME_KEY);
     assertTrue(scriptFile.equals("xyz")) ;
   }
+  
+  //Tests reading / writing a conf file with deprecation after setting
+  public void testReadWriteWithDeprecatedKeys() throws Exception {
+    Configuration conf = new Configuration();
+    conf.setBoolean("old.config.yet.to.be.deprecated", true);
+    Configuration.addDeprecation("old.config.yet.to.be.deprecated", 
+	new String[]{"new.conf.to.replace.deprecated.conf"});
+    ByteArrayOutputStream out=new ByteArrayOutputStream();
+    String fileContents;
+    try {
+      conf.writeXml(out);
+      fileContents = out.toString();
+    } finally {
+      out.close();
+    }
+    assertTrue(fileContents.contains("old.config.yet.to.be.deprecated"));
+    assertTrue(fileContents.contains("new.conf.to.replace.deprecated.conf"));
+  }
 }