com.facebook.buck.core.graph.transformation.composition

Class RightComposingComputation<KeyIntermediate extends ComputeKey<?>,Key1 extends ComputeKey<Result1>,Result1 extends ComputeResult,Key2 extends ComputeKey<Result2>,Result2 extends ComputeResult>

java.lang.Object

com.facebook.buck.core.graph.transformation.composition.RightComposingComputation<KeyIntermediate,Key1,Result1,Key2,Result2>

Type Parameters:

KeyIntermediate - the key type of the right side ComposedComputation

Key1 - the key of the base computation

Result1 - the result type of the base computation

Key2 - the key type corresponding to the final result type of this composition

Result2 - the result type of this computation

All Implemented Interfaces:

ComposedComputation<Key1,Result2>, GraphComputation<ComposedKey<Key1,Result2>,ComposedResult<ComputeKey<Result2>,Result2>>

public class RightComposingComputation<KeyIntermediate extends ComputeKey<?>,Key1 extends ComputeKey<Result1>,Result1 extends ComputeResult,Key2 extends ComputeKey<Result2>,Result2 extends ComputeResult>
extends Object
implements ComposedComputation<Key1,Result2>

An implementation of ComposedComputation that takes a base GraphComputation, a Composer, and Transformer and returns a new ComposedResult of Result2 type. This is composing from the right to left. This allows us to define a sequence of transformations K1 -> R1 to Kn -> Rn as one computation K1 -> [Rn] where computation of the next key doesn't require collecting all the results from the prior stages. This lets us perform fan-out tree shaped computations.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	RightComposingComputation.RightComposer<Key1,Result1,RightKey extends ComputeKey<?>,RightResult extends ComputeResult> Specific Composer that the right computation is a ComposedComputation

Method Summary

Modifier and Type	Method and Description
GraphComputationStage<ComposedKey<Key1,Result2>,ComposedResult<ComputeKey<Result2>,Result2>>	asStage()
com.google.common.collect.ImmutableSet<? extends ComputeKey<? extends ComputeResult>>	discoverDeps(ComposedKey<Key1,Result2> key, ComputationEnvironment env) Compute dependent keys required to compute given key, and a set of dependencies as listed by GraphComputation.discoverPreliminaryDeps(ComputeKey).
com.google.common.collect.ImmutableSet<? extends ComputeKey<? extends ComputeResult>>	discoverPreliminaryDeps(ComposedKey<Key1,Result2> key) Compute dependent keys required to compute given the current key.
ComposedComputationIdentifier<Result2>	getIdentifier()
ComposedResult<ComputeKey<Result2>,Result2>	transform(ComposedKey<Key1,Result2> key, ComputationEnvironment env) Perform a transformation identified by key Key into a final type Result.

Methods inherited from class java.lang.Object

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

Method Detail

getIdentifier

public ComposedComputationIdentifier<Result2> getIdentifier()

Specified by:

getIdentifier in interface ComposedComputation<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>

Specified by:

getIdentifier in interface GraphComputation<ComposedKey<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>,ComposedResult<ComputeKey<Result2 extends ComputeResult>,Result2 extends ComputeResult>>

Returns:

the identifier of the key for this transformation. This should match ComputeKey.getIdentifier()

transform

public ComposedResult<ComputeKey<Result2>,Result2> transform(ComposedKey<Key1,Result2> key,
                                                             ComputationEnvironment env)
                                                      throws Exception

Description copied from interface: GraphComputation

Perform a transformation identified by key Key into a final type Result. This transformation should be performed synchronously.

Specified by:

transform in interface ComposedComputation<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>

Specified by:

transform in interface GraphComputation<ComposedKey<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>,ComposedResult<ComputeKey<Result2 extends ComputeResult>,Result2 extends ComputeResult>>

Parameters:

key - The Key of the requested result

env - The execution environment containing results of keys from GraphComputation.discoverDeps(ComputeKey, ComputationEnvironment) and GraphComputation.discoverPreliminaryDeps(ComputeKey)

Returns:

The result of the transformation

Throws:

Exception

discoverDeps

public com.google.common.collect.ImmutableSet<? extends ComputeKey<? extends ComputeResult>> discoverDeps(ComposedKey<Key1,Result2> key,
                                                                                                          ComputationEnvironment env)
                                                                                                   throws Exception

Description copied from interface: GraphComputation

Compute dependent keys required to compute given key, and a set of dependencies as listed by GraphComputation.discoverPreliminaryDeps(ComputeKey). The results of those computations will be available in GraphComputation.transform(ComputeKey, ComputationEnvironment) as a part of ComputationEnvironment

Specified by:

discoverDeps in interface ComposedComputation<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>

Specified by:

discoverDeps in interface GraphComputation<ComposedKey<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>,ComposedResult<ComputeKey<Result2 extends ComputeResult>,Result2 extends ComputeResult>>

Parameters:

key - the current key to transform

env - The execution environment containing results of keys from GraphComputation.discoverPreliminaryDeps(ComputeKey)

Returns:

a set of keys that the transformation of the current key depends on

Throws:

Exception

discoverPreliminaryDeps

public com.google.common.collect.ImmutableSet<? extends ComputeKey<? extends ComputeResult>> discoverPreliminaryDeps(ComposedKey<Key1,Result2> key)

Description copied from interface: GraphComputation

Compute dependent keys required to compute given the current key. The results of those computations will be available in GraphComputation.discoverDeps(ComputeKey, ComputationEnvironment) as a part of ComputationEnvironment, and GraphComputation.transform(ComputeKey, ComputationEnvironment)

Specified by:

discoverPreliminaryDeps in interface ComposedComputation<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>

Specified by:

discoverPreliminaryDeps in interface GraphComputation<ComposedKey<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>,ComposedResult<ComputeKey<Result2 extends ComputeResult>,Result2 extends ComputeResult>>

Parameters:

key - the current key to transform

Returns:

a set of keys that the GraphComputation.discoverDeps(ComputeKey, ComputationEnvironment) and GraphComputation.transform(ComputeKey, ComputationEnvironment) of the current key depends on

asStage

public GraphComputationStage<ComposedKey<Key1,Result2>,ComposedResult<ComputeKey<Result2>,Result2>> asStage()

Specified by:

asStage in interface ComposedComputation<Key1 extends ComputeKey<Result1>,Result2 extends ComputeResult>

Returns:

a non caching GraphComputationStage for registering this computation with the GraphTransformationEngine