HDFS-3419. Cleanup LocatedBlock. Contributed by Eli Collins

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1338802 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -468,6 +468,8 @@ Release 2.0.0 - UNRELEASED
     HDFS-3416. Cleanup DatanodeID and DatanodeRegistration
     constructors used by testing. (eli)
 
+    HDFS-3419. Cleanup LocatedBlock. (eli)
+
   OPTIMIZATIONS
 
     HDFS-3024. Improve performance of stringification in addStoredBlock (todd)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LocatedBlock.java

@@ -22,11 +22,11 @@ import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.hdfs.security.token.block.BlockTokenIdentifier;
 import org.apache.hadoop.security.token.Token;
 
-/****************************************************
- * A LocatedBlock is a pair of Block, DatanodeInfo[]
- * objects.  It tells where to find a Block.
- * 
- ****************************************************/
+/**
+ * Associates a block with the Datanodes that contain its replicas
+ * and other block metadata (E.g. the file offset associated with this
+ * block, whether it is corrupt, security token, etc).
+ */
 @InterfaceAudience.Private
 @InterfaceStability.Evolving
 public class LocatedBlock {
@@ -40,19 +40,6 @@ public class LocatedBlock {
   private boolean corrupt;
   private Token<BlockTokenIdentifier> blockToken = new Token<BlockTokenIdentifier>();
 
-  public LocatedBlock() {
-    this(new ExtendedBlock(), new DatanodeInfo[0], 0L, false);
-  }
-  
-
-  public LocatedBlock(ExtendedBlock eb) {
-    this(eb, new DatanodeInfo[0], 0L, false);
-  }
-
-  public LocatedBlock(String bpid, Block b, DatanodeInfo[] locs) {
-    this(new ExtendedBlock(bpid, b), locs, -1, false); // startOffset is unknown
-  }
-
   public LocatedBlock(ExtendedBlock b, DatanodeInfo[] locs) {
     this(b, locs, -1, false); // startOffset is unknown
   }
@@ -81,14 +68,10 @@ public class LocatedBlock {
     this.blockToken = token;
   }
 
-  /**
-   */
   public ExtendedBlock getBlock() {
     return b;
   }
 
-  /**
-   */
   public DatanodeInfo[] getLocations() {
     return locs;
   }

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/protocol/LocatedBlocks.java

@@ -105,8 +105,9 @@ public class LocatedBlocks {
    * @return block if found, or null otherwise.
    */
   public int findBlock(long offset) {
-    // create fake block of size 1 as a key
-    LocatedBlock key = new LocatedBlock();
+    // create fake block of size 0 as a key
+    LocatedBlock key = new LocatedBlock(
+        new ExtendedBlock(), new DatanodeInfo[0], 0L, false);
     key.setStartOffset(offset);
     key.getBlock().setNumBytes(1);
     Comparator<LocatedBlock> comp =