src/java.base/share/classes/java/nio/channels/DatagramChannel.java

*** 517,526 ****
--- 517,528 ----
       * there are more bytes in the datagram than remain in the given buffer
       * then the remainder of the datagram is silently discarded.  Otherwise
       * this method behaves exactly as specified in the {@link
       * ReadableByteChannel} interface.  </p>
       *
+      * @return The number of bytes read, possibly zero
+      *
       * @throws  NotYetConnectedException
       *          If this channel's socket is not connected
       */
      public abstract int read(ByteBuffer dst) throws IOException;
  
*** 532,541 ****
--- 534,545 ----
       * there are more bytes in the datagram than remain in the given buffers
       * then the remainder of the datagram is silently discarded.  Otherwise
       * this method behaves exactly as specified in the {@link
       * ScatteringByteChannel} interface.  </p>
       *
+      * @return The number of bytes read, possibly zero
+      *
       * @throws  NotYetConnectedException
       *          If this channel's socket is not connected
       */
      public abstract long read(ByteBuffer[] dsts, int offset, int length)
          throws IOException;
*** 548,557 ****
--- 552,563 ----
       * there are more bytes in the datagram than remain in the given buffers
       * then the remainder of the datagram is silently discarded.  Otherwise
       * this method behaves exactly as specified in the {@link
       * ScatteringByteChannel} interface.  </p>
       *
+      * @return The number of bytes read, possibly zero
+      *
       * @throws  NotYetConnectedException
       *          If this channel's socket is not connected
       */
      public final long read(ByteBuffer[] dsts) throws IOException {
          return read(dsts, 0, dsts.length);