water

Class RPC<V extends DTask>

java.lang.Object

water.RPC<V>

All Implemented Interfaces:

java.lang.Comparable<java.util.concurrent.Delayed>, java.util.concurrent.Delayed, java.util.concurrent.Future<V>, jsr166y.ForkJoinPool.ManagedBlocker

public class RPC<V extends DTask>
extends java.lang.Object
implements java.util.concurrent.Future<V>, java.util.concurrent.Delayed, jsr166y.ForkJoinPool.ManagedBlocker

A remotely executed FutureTask. Flow is: 1- Build a DTask (or subclass). This object will be replicated remotely. 2- Make a RPC object, naming the target Node. Call (re)call(). Call get() to block for result, or cancel() or isDone(), etc. Caller can also arrange for caller.tryComplete() to be called in a F/J thread, to support completion style execution (i.e. Continuation Passing Style). 3- DTask will be serialized and sent to the target; small objects via UDP and large via TCP (using AutoBuffer and auto-gen serializers). 4- An RPC UDP control packet will be sent to target; this will also contain the DTask if its small enough. 4.5- The network may replicate (or drop) the UDP packet. Dups may arrive. 4.5- Sender may timeout, and send dup control UDP packets. 5- Target will capture a UDP packet, and begin filtering dups (via task#). 6- Target will deserialize the DTask, and call DTask.invoke() in a F/J thread. 6.5- Target continues to filter (and drop) dup UDP sends (and timeout resends) 7- Target finishes call, and puts result in DTask. 8- Target serializes result and sends to back to sender. 9- Target sends an ACK back (may be combined with the result if small enough) 10- Target puts the ACK in H2ONode.TASKS for later filtering. 10.5- Target receives dup UDP request, then replies with ACK back. 11- Sender receives ACK result; deserializes; notifies waiters 12- Sender sends ACKACK back 12.5- Sender recieves dup ACK's, sends dup ACKACK's back 13- Target recieves ACKACK, removes TASKS tracking

Constructor Summary

Constructors

Constructor and Description
RPC(H2ONode target, V dtask)

Method Summary

Methods

Modifier and Type	Method and Description
RPC<V>	addCompleter(H2O.H2OCountedCompleter task)
boolean	block() Possibly blocks the current thread, for example waiting for a lock or condition.
RPC<V>	call()
static <DT extends DTask> RPC<DT>	call(H2ONode target, DT dtask)
boolean	cancel(boolean mayInterruptIfRunning)
int	compareTo(java.util.concurrent.Delayed t)
V	get()
V	get(long timeout, java.util.concurrent.TimeUnit unit)
long	getDelay(java.util.concurrent.TimeUnit unit)
boolean	isCancelled()
boolean	isDone()
boolean	isReleasable() Returns true if blocking is unnecessary.
protected int	response(AutoBuffer ab)

Methods inherited from class java.lang.Object

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

Constructor Detail

RPC

public RPC(H2ONode target,
   V dtask)

Method Detail

call

public static <DT extends DTask> RPC<DT> call(H2ONode target,
                              DT dtask)

call

public RPC<V> call()

get

public V get()

Specified by:

get in interface java.util.concurrent.Future<V extends DTask>

isReleasable

public boolean isReleasable()

Description copied from interface: jsr166y.ForkJoinPool.ManagedBlocker

Returns true if blocking is unnecessary.

Specified by:

isReleasable in interface jsr166y.ForkJoinPool.ManagedBlocker

block

public boolean block()
              throws java.lang.InterruptedException

Description copied from interface: jsr166y.ForkJoinPool.ManagedBlocker

Possibly blocks the current thread, for example waiting for a lock or condition.

Specified by:

block in interface jsr166y.ForkJoinPool.ManagedBlocker

Returns:

true if no additional blocking is necessary (i.e., if isReleasable would return true)

Throws:

java.lang.InterruptedException - if interrupted while waiting (the method is not required to do so, but is allowed to)

get

public final V get(long timeout,
    java.util.concurrent.TimeUnit unit)

Specified by:

get in interface java.util.concurrent.Future<V extends DTask>

isDone

public final boolean isDone()

Specified by:

isDone in interface java.util.concurrent.Future<V extends DTask>

isCancelled

public final boolean isCancelled()

Specified by:

isCancelled in interface java.util.concurrent.Future<V extends DTask>

cancel

public final boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface java.util.concurrent.Future<V extends DTask>

response

protected int response(AutoBuffer ab)

addCompleter

public RPC<V> addCompleter(H2O.H2OCountedCompleter task)

getDelay

public final long getDelay(java.util.concurrent.TimeUnit unit)

Specified by:

getDelay in interface java.util.concurrent.Delayed

compareTo

public final int compareTo(java.util.concurrent.Delayed t)

Specified by:

compareTo in interface java.lang.Comparable<java.util.concurrent.Delayed>