org.apache.hadoop.hbase.ipc

Class BlockingRpcConnection.CallSender

java.lang.Object

java.lang.Thread

org.apache.hadoop.hbase.ipc.BlockingRpcConnection.CallSender

All Implemented Interfaces:

Runnable

Enclosing class:

BlockingRpcConnection

private class BlockingRpcConnection.CallSender
extends Thread

If the client wants to interrupt its calls easily (i.e. call Thread#interrupt), it gets into a java issue: an interruption during a write closes the socket/channel. A way to avoid this is to use a different thread for writing. This way, on interruptions, we either cancel the writes or ignore the answer if the write is already done, but we don't stop the write in the middle. This adds a thread per region server in the client, so it's kept as an option.

The implementation is simple: the client threads adds their call to the queue, and then wait for an answer. The CallSender blocks on the queue, and writes the calls one after the other. On interruption, the client cancels its call. The CallSender checks that the call has not been canceled before writing it.

When the connection closes, all the calls not yet sent are dismissed. The client thread is notified with an appropriate exception, as if the call was already sent but the answer not yet received.

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

Thread.State, Thread.UncaughtExceptionHandler

Field Summary

Fields

Modifier and Type	Field and Description
private Queue<Call>	callsToWrite
private int	maxQueueSize

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor and Description
CallSender(String name, org.apache.hadoop.conf.Configuration conf)

Method Summary

Modifier and Type	Method and Description
void	cleanup(IOException e) Cleans the call not yet sent when we finish.
void	remove(Call call)
void	run() Reads the call from the queue, write them on the socket.
void	sendCall(Call call)

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

callsToWrite

private final Queue<Call> callsToWrite

maxQueueSize

private final int maxQueueSize

Constructor Detail

CallSender

public CallSender(String name,
                  org.apache.hadoop.conf.Configuration conf)

Method Detail

sendCall

public void sendCall(Call call)
              throws IOException

Throws:

IOException

remove

public void remove(Call call)

run

public void run()

Reads the call from the queue, write them on the socket.

Specified by:

run in interface Runnable

Overrides:

run in class Thread

cleanup

public void cleanup(IOException e)

Cleans the call not yet sent when we finish.