HBaseClient retries even though a DoNotRetryException was thrown

Throwing a DoNotRetryIOException inside Writable.write(Dataoutput) method doesn't prevent HBase from retrying. Debugging the code locally, I figured that the bug lies in the way HBaseClient simply throws an IOException when it sees that a connection has been closed unexpectedly.

Method:
public Writable call(Writable param, InetSocketAddress addr,
Class<? extends VersionedProtocol> protocol,
User ticket, int rpcTimeout)

Excerpt of code where the bug is present:
while (!call.done) {
if (connection.shouldCloseConnection.get())

{ throw new IOException("Unexpected closed connection"); }

Throwing this IOException causes the ServerCallable.translateException(t) to be a no-op resulting in HBase retrying.

From my limited view and understanding of the code, one way I could think of handling this is by looking at the closeConnection member variable of a connection to determine what kind of exception should be thrown.

Specifically, when a connection is closed, the current code does this:

protected synchronized void markClosed(IOException e) {
if (shouldCloseConnection.compareAndSet(false, true))

{ closeException = e; notifyAll(); }

}

Within HBaseClient's call method, the code could possibly be modified to:

while (!call.done) {
if (connection.shouldCloseConnection.get() ) {
if(connection.closeException instanceof DoNotRetryIOException)

{ throw closeException; } throw new IOException("Unexpected closed connection"); }