org.gridgain.grid.util.lang

Class GridComputeJobWrapper

java.lang.Object

org.gridgain.grid.util.lang.GridMetadataAwareAdapter

org.gridgain.grid.util.lang.GridComputeJobWrapper

All Implemented Interfaces:

Serializable, Callable<Object>, GridComputeJob, GridMetadataAware, GridPeerDeployAware

public class GridComputeJobWrapper
extends GridMetadataAwareAdapter
implements GridComputeJob, Callable<Object>, GridPeerDeployAware

Convenient wrapper for grid job. It allows to create a job clone in cases when the same job needs to be cloned to multiple grid nodes during mapping phase of task execution.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
GridComputeJobWrapper(GridComputeJob job, boolean cpMeta) Creates a wrapper with given grid job.

Method Summary

Methods

Modifier and Type	Method and Description
Object	call()
void	cancel() This method is called when system detects that completion of this job can no longer alter the overall outcome (for example, when parent task has already reduced the results).
ClassLoader	classLoader() Gets class loader for the class.
Class<?>	deployClass() Gets top level user class being deployed.
Object	execute() Executes this job.
String	toString()
GridComputeJob	wrappedJob() Gets wrapped job.

Methods inherited from class org.gridgain.grid.util.lang.GridMetadataAwareAdapter

addMeta, addMetaIfAbsent, addMetaIfAbsent, allMeta, clone, copyMeta, copyMeta, hasMeta, hasMeta, meta, putMetaIfAbsent, putMetaIfAbsent, readExternalMeta, removeMeta, removeMeta, replaceMeta, writeExternalMeta

Methods inherited from class java.lang.Object

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

Constructor Detail

GridComputeJobWrapper

public GridComputeJobWrapper(GridComputeJob job,
                     boolean cpMeta)

Creates a wrapper with given grid job. If job implements GridMetadataAware interface and copyMeta is true - the metadata information will be copied from given job to this wrapper.

Parameters:

job - Job to wrap.

cpMeta - Whether or not to copy metadata in case when job implements GridMetadataAware interface.

Method Detail

wrappedJob

public GridComputeJob wrappedJob()

Gets wrapped job.

Returns:

Wrapped job.

call

@Nullable
public final Object call()
                  throws Exception

Specified by:

call in interface Callable<Object>

Throws:

Exception

deployClass

public Class<?> deployClass()

Gets top level user class being deployed.

Specified by:

deployClass in interface GridPeerDeployAware

Returns:

Top level user deployed class.

classLoader

public ClassLoader classLoader()

Gets class loader for the class. This class loader must be able to load the class returned from GridPeerDeployAware.deployClass() as well as all of its dependencies.

Note that in most cases the class loader returned from this method and the class loader for the class returned from GridPeerDeployAware.deployClass() method will be the same. If they are not the same, it is required that the class loader returned from this method still has to be able to load the deploy class and all its dependencies.

Specified by:

classLoader in interface GridPeerDeployAware

Returns:

Class loader for the class.

cancel

public void cancel()

This method is called when system detects that completion of this job can no longer alter the overall outcome (for example, when parent task has already reduced the results). Job is also cancelled when GridFuture.cancel() is called.

Note that job cancellation is only a hint, and just like with Thread.interrupt() method, it is really up to the actual job instance to gracefully finish execution and exit.

Specified by:

cancel in interface GridComputeJob

execute

public Object execute()
               throws GridException

Executes this job.

Specified by:

execute in interface GridComputeJob

Returns:

Job execution result (possibly null). This result will be returned in GridComputeJobResult.getData() method passed into GridComputeTask.result(GridComputeJobResult, List) task method on caller node.

Throws:

GridException - If job execution caused an exception. This exception will be returned in GridComputeJobResult.getException() method passed into GridComputeTask.result(GridComputeJobResult, List) task method on caller node. If execution produces a RuntimeException or Error, then it will be wrapped into GridException.

toString

public String toString()

Overrides:

toString in class Object