HADOOP-7058. Expose number of bytes in FSOutputSummer buffer to implementatins. Contributed by Todd Lipcon.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1044148 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -29,6 +29,9 @@ Trunk (unreleased changes)
     HADOOP-7060. A more elegant FileSystem#listCorruptFileBlocks API.
     (Patrick Kling via hairong)
 
+    HADOOP-7058. Expose number of bytes in FSOutputSummer buffer to
+    implementatins. (Todd Lipcon via hairong)
+
   OPTIMIZATIONS
 
   BUG FIXES

src/java/org/apache/hadoop/fs/FSOutputSummer.java

@@ -140,6 +140,13 @@ abstract public class FSOutputSummer extends OutputStream {
     }
   }
 
+  /**
+   * Return the number of valid bytes currently in the buffer.
+   */
+  protected synchronized int getBufferedDataSize() {
+    return count;
+  }
+  
   /** Generate checksum for the data chunk and output data chunk & checksum
    * to the underlying output stream. If keep is true then keep the
    * current checksum intact, do not reset it.