org.gridgain.grid.kernal.processors.cache.query.jdbc

Class GridCacheQueryJdbcValidationTask

java.lang.Object

org.gridgain.grid.compute.GridComputeTaskAdapter<T,R>

org.gridgain.grid.compute.GridComputeTaskSplitAdapter<String,Boolean>

org.gridgain.grid.kernal.processors.cache.query.jdbc.GridCacheQueryJdbcValidationTask

All Implemented Interfaces:

Serializable, GridComputeTask<String,Boolean>

public class GridCacheQueryJdbcValidationTask
extends GridComputeTaskSplitAdapter<String,Boolean>

Task to validate connection. Checks that cache with provided name exists in grid.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
GridCacheQueryJdbcValidationTask()

Method Summary

Methods

Modifier and Type	Method and Description
Boolean	reduce(List<GridComputeJobResult> results) Reduces (or aggregates) results received so far into one compound result to be returned to caller via GridComputeTaskFuture.get() method.
protected Collection<? extends GridComputeJob>	split(int gridSize, String cacheName) This is a simplified version of GridComputeTask.map(List, Object) method.

Methods inherited from class org.gridgain.grid.compute.GridComputeTaskSplitAdapter

map

Methods inherited from class org.gridgain.grid.compute.GridComputeTaskAdapter

result

Methods inherited from class java.lang.Object

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

Constructor Detail

GridCacheQueryJdbcValidationTask

public GridCacheQueryJdbcValidationTask()

Method Detail

split

protected Collection<? extends GridComputeJob> split(int gridSize,
                                         @Nullable
                                         String cacheName)
                                              throws GridException

This is a simplified version of GridComputeTask.map(List, Object) method.

This method basically takes given argument and splits it into a collection of GridComputeJob using provided grid size as indication of how many node are available. These jobs will be randomly mapped to available grid nodes. Note that if number of jobs is greater than number of grid nodes (i.e, grid size), the grid nodes will be reused and some jobs will end up on the same grid nodes.

Specified by:

split in class GridComputeTaskSplitAdapter<String,Boolean>

Parameters:

gridSize - Number of available grid nodes. Note that returned number of jobs can be less, equal or greater than this grid size.

cacheName - Task execution argument. Can be null.

Returns:

Collection of grid jobs. These jobs will be randomly mapped to available grid nodes. Note that if number of jobs is greater than number of grid nodes (i.e, grid size), the grid nodes will be reused and some jobs will end up on the same grid nodes.

Throws:

GridException - Thrown in case of any errors.

See Also:

GridComputeTask.map(List, Object)

reduce

public Boolean reduce(List<GridComputeJobResult> results)
               throws GridException

Reduces (or aggregates) results received so far into one compound result to be returned to caller via GridComputeTaskFuture.get() method.

Note, that if some jobs did not succeed and could not be failed over then the list of results passed into this method will include the failed results. Otherwise, failed results will not be in the list.

Parameters:

results - Received results of broadcasted remote executions. Note that if task class has GridComputeTaskNoResultCache annotation, then this list will be empty.

Returns:

Grid job result constructed from results of remote executions.

Throws:

GridException - If reduction or results caused an error. This exception will be thrown out of GridComputeTaskFuture.get() method.