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# Class ComputeTaskSplitAdapter<TArg, TJobRes, TTaskRes>

This class defines simplified adapter for IComputeTask<TArg, TJobRes, TRes>. This adapter can be used when jobs can be randomly assigned to available Ignite nodes. This adapter is sufficient in most homogeneous environments where all nodes are equally suitable for executing grid job, see Split(Int32, TArg) method for more details.

##### Inheritance

System.Object
ComputeTaskAdapter<TArg, TJobRes, TTaskRes>
ComputeTaskSplitAdapter<TArg, TJobRes, TTaskRes>

##### Implements

IComputeTask<TArg, TJobRes, TTaskRes>

##### Inherited Members

ComputeTaskAdapter<TArg, TJobRes, TTaskRes>.OnResult(IComputeJobResult<TJobRes>, IList<IComputeJobResult<TJobRes>>)
ComputeTaskAdapter<TArg, TJobRes, TTaskRes>.Map(IList<IClusterNode>, TArg)
ComputeTaskAdapter<TArg, TJobRes, TTaskRes>.Reduce(IList<IComputeJobResult<TJobRes>>)

###### Namespace: Apache.Ignite.Core.Compute

###### Assembly: Apache.Ignite.Core.dll

##### Syntax

    public abstract class ComputeTaskSplitAdapter<TArg, TJobRes, TTaskRes> : ComputeTaskAdapter<TArg, TJobRes, TTaskRes>, IComputeTask<TArg, TJobRes, TTaskRes>

##### Type Parameters

Name | Description
--- | ---
TArg |
TJobRes |
TTaskRes |

### Methods

#### Map(IList<IClusterNode>, TArg)

This method is called to map or split Ignite task into multiple Ignite jobs. This is the first method that gets called when task execution starts.

##### Declaration

    public override IDictionary<IComputeJob<TJobRes>, IClusterNode> Map(IList<IClusterNode> subgrid, TArg arg)

##### Parameters

Type | Name | Description
--- | --- | ---
IList<IClusterNode> | subgrid | Nodes available for this task execution. Note that order of nodes is guaranteed to be randomized by container. This ensures that every time you simply iterate through Ignite nodes, the order of nodes will be random which over time should result into all nodes being used equally.
TArg | arg | Task execution argument. Can be `null`. This is the same argument as the one passed into `ICompute.Execute()` methods.

##### Returns

Type | Description
--- | ---
IDictionary<IComputeJob<TJobRes>, IClusterNode> | Map of Ignite jobs assigned to subgrid node. If `null` or empty map is returned, exception will be thrown.

##### Overrides

Apache.Ignite.Core.Compute.ComputeTaskAdapter<TArg, TJobRes, TTaskRes>.Map(IList<Apache.Ignite.Core.Cluster.IClusterNode>, TArg)

##### Exceptions

Type | Condition
--- | ---
IgniteException | Split returned no jobs.

#### Split(Int32, TArg)

This is a simplified version of Map(IList<IClusterNode>, TArg) method.

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

##### Declaration

    protected abstract ICollection<IComputeJob<TJobRes>> Split(int gridSize, TArg arg)

##### Parameters

Type | Name | Description
--- | --- | ---
System.Int32 | gridSize | Number of available Ignite nodes. Note that returned number of jobs can be less, equal or greater than this grid size.
TArg | arg | Task execution argument. Can be `null`.

##### Returns

Type | Description
--- | ---
ICollection<IComputeJob<TJobRes>> |

### Implements

IComputeTask<TArg, TJobRes, TRes>