water

Class DTask<T extends DTask>

java.lang.Object

jsr166y.ForkJoinTask<java.lang.Void>

jsr166y.CountedCompleter

water.H2O.H2OCountedCompleter

water.DTask<T>

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.util.concurrent.Future<java.lang.Void>, Freezable

Direct Known Subclasses:

Atomic, DRemoteTask, DTask.DKeyTask, FetchClazz, FetchId, MRTask2, NOPTask, TaskGetKey, TaskPutKey, TaskSendKey

public abstract class DTask<T extends DTask>
extends H2O.H2OCountedCompleter
implements Freezable

Objects which are passed and remotely executed.

Efficient serialization methods for subclasses will be automatically generated, but explicit ones can be provided. Transient fields will not be mirrored between the VMs.

1. On the local vm, this task will be serialized and sent to a remote.
2. On the remote, the task will be deserialized.
3. On the remote, the H2ONode invoke method will be executed.
4. On the remote, the task will be serialized and sent to the local vm
5. On the local vm, the task will be deserialized into the original instance
6. On the local vm, the onAck() method will be executed.
7. On the remote, the onAckAck() method will be executed.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DTask.DKeyTask<T extends DTask.DKeyTask,V extends Iced> Task to be executed at home of the given key.

Field Summary

Fields

Modifier and Type	Field and Description
protected DException	_ex

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	DTask()
	DTask(H2O.H2OCountedCompleter completer)

Method Summary

Methods

Modifier and Type	Method and Description
void	copyOver(Freezable other)
void	dinvoke(H2ONode sender) Top-level remote execution hook.
int	frozenType() Return the cluster-wide-unique 2-byte type ID for instances of this class
DException.DistributedException	getDException()
boolean	hasException()
boolean	logVerbose() Override to remove 2 lines of logging per RPC.
<F extends Freezable> F	newInstance() Make a new instance of class 'this' with the empty constructor
void	onAck() 2nd top-level execution hook.
void	onAckAck() 3rd top-level execution hook.
<T extends Freezable> T	read(AutoBuffer bb) Deserialize from the AutoBuffer into a pre-existing 'this' object.
void	setException(java.lang.Throwable ex)
DocGen.FieldDoc[]	toDocField() Reflective list of fields
AutoBuffer	write(AutoBuffer bb) Serialize the 'this' object into the AutoBuffer, returning the AutoBuffer.
AutoBuffer	writeJSONFields(AutoBuffer bb) Serialize the 'this' object into the AutoBuffer, returning the AutoBuffer.

Methods inherited from class water.H2O.H2OCountedCompleter

clone, compute, compute2, onExceptionalCompletion, priority

Methods inherited from class jsr166y.CountedCompleter

addToPendingCount, compareAndSetPendingCount, complete, exec, getCompleter, getPendingCount, getRawResult, onCompletion, setCompleter, setPendingCount, setRawResult, tryComplete

Methods inherited from class jsr166y.ForkJoinTask

adapt, adapt, adapt, cancel, compareAndSetForkJoinTaskTag, completeExceptionally, fork, get, get, getException, getForkJoinTaskTag, getPool, getQueuedTaskCount, getSurplusQueuedTaskCount, helpQuiesce, inForkJoinPool, invoke, invokeAll, invokeAll, invokeAll, isCancelled, isCompletedAbnormally, isCompletedNormally, isDone, join, peekNextLocalTask, pollNextLocalTask, pollTask, quietlyComplete, quietlyInvoke, quietlyJoin, reinitialize, setForkJoinTaskTag, tryUnfork

Methods inherited from class java.lang.Object

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

Field Detail

_ex

protected DException _ex

Constructor Detail

DTask

protected DTask()

DTask

public DTask(H2O.H2OCountedCompleter completer)

Method Detail

hasException

public final boolean hasException()

setException

public void setException(java.lang.Throwable ex)

getDException

public DException.DistributedException getDException()

dinvoke

public void dinvoke(H2ONode sender)

Top-level remote execution hook. Called on the remote.

onAck

public void onAck()

2nd top-level execution hook. After the primary task has received a result (ACK) and before we have sent an ACKACK, this method is executed on the local vm. Transients from the local vm are available here.

onAckAck

public void onAckAck()

3rd top-level execution hook. After the original vm sent an ACKACK, this method is executed on the remote. Transients from the remote vm are available here.

logVerbose

public boolean logVerbose()

Override to remove 2 lines of logging per RPC. 0.5M RPC's will lead to 1M lines of logging at about 50 bytes/line produces 50M of log file, which will swamp all other logging output.

write

public AutoBuffer write(AutoBuffer bb)

Description copied from interface: Freezable

Serialize the 'this' object into the AutoBuffer, returning the AutoBuffer.

Specified by:

write in interface Freezable

read

public <T extends Freezable> T read(AutoBuffer bb)

Description copied from interface: Freezable

Deserialize from the AutoBuffer into a pre-existing 'this' object.

Specified by:

read in interface Freezable

newInstance

public <F extends Freezable> F newInstance()

Description copied from interface: Freezable

Make a new instance of class 'this' with the empty constructor

Specified by:

newInstance in interface Freezable

frozenType

public int frozenType()

Description copied from interface: Freezable

Return the cluster-wide-unique 2-byte type ID for instances of this class

Specified by:

frozenType in interface Freezable

writeJSONFields

public AutoBuffer writeJSONFields(AutoBuffer bb)

Description copied from interface: Freezable

Serialize the 'this' object into the AutoBuffer, returning the AutoBuffer. Output is legal JSON.

Specified by:

writeJSONFields in interface Freezable

toDocField

public DocGen.FieldDoc[] toDocField()

Description copied from interface: Freezable

Reflective list of fields

Specified by:

toDocField in interface Freezable

copyOver

public void copyOver(Freezable other)