HADOOP-8172. Configuration no longer sets all keys in a deprecated key list. (Anupam Seth via bobby)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1332821 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -447,6 +447,9 @@ Release 2.0.0 - UNRELEASED
     HADOOP-8317. Update maven-assembly-plugin to 2.3 - fix build on FreeBSD
     (Radim Kolar via bobby)
 
+    HADOOP-8172. Configuration no longer sets all keys in a deprecated key 
+    list. (Anupam Seth via bobby)
+
 Release 0.23.3 - UNRELEASED
 
   INCOMPATIBLE CHANGES

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

@@ -33,6 +33,7 @@
 import java.net.InetSocketAddress;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Enumeration;
@@ -269,10 +270,18 @@ private final String getWarningMessage(String key) {
    * This is to be used only by the developers in order to add deprecation of
    * keys, and attempts to call this method after loading resources once,
    * would lead to <tt>UnsupportedOperationException</tt>
+   * 
+   * If a key is deprecated in favor of multiple keys, they are all treated as 
+   * aliases of each other, and setting any one of them resets all the others 
+   * to the new value.
+   * 
    * @param key
    * @param newKeys
    * @param customMessage
+   * @deprecated use {@link addDeprecation(String key, String newKey,
+      String customMessage)} instead
    */
+  @Deprecated
   public synchronized static void addDeprecation(String key, String[] newKeys,
       String customMessage) {
     if (key == null || key.length() == 0 ||
@@ -289,6 +298,43 @@ public synchronized static void addDeprecation(String key, String[] newKeys,
     }
   }
   
+  /**
+   * Adds the deprecated key to the deprecation map.
+   * It does not override any existing entries in the deprecation map.
+   * This is to be used only by the developers in order to add deprecation of
+   * keys, and attempts to call this method after loading resources once,
+   * would lead to <tt>UnsupportedOperationException</tt>
+   * 
+   * @param key
+   * @param newKey
+   * @param customMessage
+   */
+  public synchronized static void addDeprecation(String key, String newKey,
+	      String customMessage) {
+	  addDeprecation(key, new String[] {newKey}, customMessage);
+  }
+
+  /**
+   * Adds the deprecated key to the deprecation map when no custom message
+   * is provided.
+   * It does not override any existing entries in the deprecation map.
+   * This is to be used only by the developers in order to add deprecation of
+   * keys, and attempts to call this method after loading resources once,
+   * would lead to <tt>UnsupportedOperationException</tt>
+   * 
+   * If a key is deprecated in favor of multiple keys, they are all treated as 
+   * aliases of each other, and setting any one of them resets all the others 
+   * to the new value.
+   * 
+   * @param key Key that is to be deprecated
+   * @param newKeys list of keys that take up the values of deprecated key
+   * @deprecated use {@link addDeprecation(String key, String newKey)} instead
+   */
+  @Deprecated
+  public synchronized static void addDeprecation(String key, String[] newKeys) {
+    addDeprecation(key, newKeys, null);
+  }
+  
   /**
    * Adds the deprecated key to the deprecation map when no custom message
    * is provided.
@@ -298,10 +344,10 @@ public synchronized static void addDeprecation(String key, String[] newKeys,
    * would lead to <tt>UnsupportedOperationException</tt>
    * 
    * @param key Key that is to be deprecated
-   * @param newKeys list of keys that take up the values of deprecated key
+   * @param newKey key that takes up the value of deprecated key
    */
-  public synchronized static void addDeprecation(String key, String[] newKeys) {
+  public synchronized static void addDeprecation(String key, String newKey) {
-    addDeprecation(key, newKeys, null);
+	addDeprecation(key, new String[] {newKey}, null);
   }
   
   /**
@@ -322,16 +368,26 @@ public static boolean isDeprecated(String key) {
    * @param name property name.
    * @return alternate name.
    */
-  private String getAlternateName(String name) {
+  private String[] getAlternateNames(String name) {
-    String altName;
+    String oldName, altNames[] = null;
     DeprecatedKeyInfo keyInfo = deprecatedKeyMap.get(name);
-    if (keyInfo != null) {
+    if (keyInfo == null) {
-      altName = (keyInfo.newKeys.length > 0) ? keyInfo.newKeys[0] : null;
+      altNames = (reverseDeprecatedKeyMap.get(name) != null ) ? 
+        new String [] {reverseDeprecatedKeyMap.get(name)} : null;
+      if(altNames != null && altNames.length > 0) {
+    	//To help look for other new configs for this deprecated config
+    	keyInfo = deprecatedKeyMap.get(altNames[0]);
       }      
-    else {
-      altName = reverseDeprecatedKeyMap.get(name);
     } 
-    return altName;
+    if(keyInfo != null && keyInfo.newKeys.length > 0) {
+      List<String> list = new ArrayList<String>(); 
+      if(altNames != null) {
+    	  list.addAll(Arrays.asList(altNames));
+      }
+      list.addAll(Arrays.asList(keyInfo.newKeys));
+      altNames = list.toArray(new String[list.size()]);
+    }
+    return altNames;
   }
 
   /**
@@ -346,24 +402,29 @@ private String getAlternateName(String name) {
    * @return the first property in the list of properties mapping
    *         the <code>name</code> or the <code>name</code> itself.
    */
-  private String handleDeprecation(String name) {
+  private String[] handleDeprecation(String name) {
+    ArrayList<String > names = new ArrayList<String>();
 	if (isDeprecated(name)) {
       DeprecatedKeyInfo keyInfo = deprecatedKeyMap.get(name);
       warnOnceIfDeprecated(name);
       for (String newKey : keyInfo.newKeys) {
         if(newKey != null) {
-          name = newKey;
+          names.add(newKey);
-          break;
         }
       }
     }
-    String deprecatedKey = reverseDeprecatedKeyMap.get(name);
+    if(names.size() == 0) {
-    if (deprecatedKey != null && !getOverlay().containsKey(name) &&
+    	names.add(name);
+    }
+    for(String n : names) {
+	  String deprecatedKey = reverseDeprecatedKeyMap.get(n);
+	  if (deprecatedKey != null && !getOverlay().containsKey(n) &&
 	      getOverlay().containsKey(deprecatedKey)) {
-      getProps().setProperty(name, getOverlay().getProperty(deprecatedKey));
+	    getProps().setProperty(n, getOverlay().getProperty(deprecatedKey));
-      getOverlay().setProperty(name, getOverlay().getProperty(deprecatedKey));
+	    getOverlay().setProperty(n, getOverlay().getProperty(deprecatedKey));
 	  }
-    return name;
+    }
+    return names.toArray(new String[names.size()]);
   }
  
   private void handleDeprecation() {
@@ -595,8 +656,12 @@ private String substituteVars(String expr) {
    *         or null if no such property exists.
    */
   public String get(String name) {
-    name = handleDeprecation(name);
+    String[] names = handleDeprecation(name);
-    return substituteVars(getProps().getProperty(name));
+    String result = null;
+    for(String n : names) {
+      result = substituteVars(getProps().getProperty(n));
+    }
+    return result;
   }
   
   /**
@@ -633,8 +698,12 @@ public String getTrimmed(String name) {
    *         its replacing property and null if no such property exists.
    */
   public String getRaw(String name) {
-    name = handleDeprecation(name);
+    String[] names = handleDeprecation(name);
-    return getProps().getProperty(name);
+    String result = null;
+    for(String n : names) {
+      result = getProps().getProperty(n);
+    }
+    return result;
   }
 
   /** 
@@ -652,11 +721,13 @@ public void set(String name, String value) {
     getOverlay().setProperty(name, value);
     getProps().setProperty(name, value);
     updatingResource.put(name, UNKNOWN_RESOURCE);
-    String altName = getAlternateName(name);
+    String[] altNames = getAlternateNames(name);
-    if (altName != null) {
+    if (altNames != null && altNames.length > 0) {
+      for(String altName : altNames) {
     	getOverlay().setProperty(altName, value);
         getProps().setProperty(altName, value);
       }
+    }
     warnOnceIfDeprecated(name);
   }
 
@@ -671,14 +742,16 @@ private void warnOnceIfDeprecated(String name) {
    * Unset a previously set property.
    */
   public synchronized void unset(String name) {
-    String altName = getAlternateName(name);
+    String[] altNames = getAlternateNames(name);
     getOverlay().remove(name);
     getProps().remove(name);
-    if (altName !=null) {
+    if (altNames !=null && altNames.length > 0) {
+      for(String altName : altNames) {
     	getOverlay().remove(altName);
     	getProps().remove(altName);
       }
     }
+  }
 
   /**
    * Sets a property if it is currently unset.
@@ -711,8 +784,12 @@ private synchronized Properties getOverlay() {
    *         doesn't exist.                    
    */
   public String get(String name, String defaultValue) {
-    name = handleDeprecation(name);
+    String[] names = handleDeprecation(name);
-    return substituteVars(getProps().getProperty(name, defaultValue));
+    String result = null;
+    for(String n : names) {
+      result = substituteVars(getProps().getProperty(n, defaultValue));
+    }
+    return result;
   }
     
   /** 

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

@@ -164,7 +164,7 @@ public void testDeprecation() throws IOException {
     conf.set("Y", "y");
     conf.set("Z", "z");
     // get old key
-    assertEquals("y", conf.get("X"));
+    assertEquals("z", conf.get("X"));
   }
 
   /**

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

@@ -18,10 +18,15 @@
 
 package org.apache.hadoop.conf;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
 import java.io.ByteArrayOutputStream;
+import java.util.Map;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.CommonConfigurationKeys;
+import org.junit.Test;
 
 import junit.framework.TestCase;
 
@@ -53,4 +58,49 @@ public void testReadWriteWithDeprecatedKeys() throws Exception {
     assertTrue(fileContents.contains("old.config.yet.to.be.deprecated"));
     assertTrue(fileContents.contains("new.conf.to.replace.deprecated.conf"));
   }
+  
+  @Test
+  public void testIteratorWithDeprecatedKeysMappedToMultipleNewKeys() {
+    Configuration conf = new Configuration();
+    Configuration.addDeprecation("dK", new String[]{"nK1", "nK2"});
+    conf.set("k", "v");
+    conf.set("dK", "V");
+    assertEquals("V", conf.get("dK"));
+    assertEquals("V", conf.get("nK1"));
+    assertEquals("V", conf.get("nK2"));
+    conf.set("nK1", "VV");
+    assertEquals("VV", conf.get("dK"));
+    assertEquals("VV", conf.get("nK1"));
+    assertEquals("VV", conf.get("nK2"));
+    conf.set("nK2", "VVV");
+    assertEquals("VVV", conf.get("dK"));
+    assertEquals("VVV", conf.get("nK2"));
+    assertEquals("VVV", conf.get("nK1"));
+    boolean kFound = false;
+    boolean dKFound = false;
+    boolean nK1Found = false;
+    boolean nK2Found = false;
+    for (Map.Entry<String, String> entry : conf) {
+      if (entry.getKey().equals("k")) {
+        assertEquals("v", entry.getValue());
+        kFound = true;
+      }
+      if (entry.getKey().equals("dK")) {
+        assertEquals("VVV", entry.getValue());
+        dKFound = true;
+      }
+      if (entry.getKey().equals("nK1")) {
+        assertEquals("VVV", entry.getValue());
+        nK1Found = true;
+      }
+      if (entry.getKey().equals("nK2")) {
+        assertEquals("VVV", entry.getValue());
+        nK2Found = true;
+      }
+    }
+    assertTrue("regular Key not found", kFound);
+    assertTrue("deprecated Key not found", dKFound);
+    assertTrue("new Key 1 not found", nK1Found);
+    assertTrue("new Key 2 not found", nK2Found);
+  }
 }