cascading.flow
Interface FlowElement

All Known Implementing Classes:

CoGroup, Dfs, Each, ElementGraph.Extent, EndPipe, Every, Group, GroupBy, Hfs, Lfs, MultiTap, Operator, Pipe, S3fs, SourceTap, SubAssembly, Tap, TempHfs

public interface FlowElement

Interface FlowElement is a utility interface used internally to simplify DAG management.

Method Summary

Scope	outgoingScopeFor(Set<Scope> incomingScopes) Method outgoingScopeFor returns the Scope this FlowElement hands off to the next FlowElement.
Fields	resolveFields(Scope scope) Method resolveFields returns the actual field names represented by the given Scope.
Fields	resolveIncomingOperationFields(Scope incomingScope) Method resolveIncomingOperationFields resolves the incoming scopes to the actual incoming operation field names.

Method Detail

outgoingScopeFor

Scope outgoingScopeFor(Set<Scope> incomingScopes)

Method outgoingScopeFor returns the Scope this FlowElement hands off to the next FlowElement.

Parameters:

incomingScopes - of type Set

Returns:

Scope

resolveIncomingOperationFields

Fields resolveIncomingOperationFields(Scope incomingScope)

Method resolveIncomingOperationFields resolves the incoming scopes to the actual incoming operation field names.

Parameters:

incomingScope - of type Scope

Returns:

Fields

resolveFields

Fields resolveFields(Scope scope)

Method resolveFields returns the actual field names represented by the given Scope. The scope may be incoming or outgoing in relation to this FlowElement instance.

Parameters:

scope - of type Scope

Returns:

Fields