Package com.yahoo.searchlib.rankingexpression.transform

Class ExpressionTransformer<CONTEXT extends TransformContext>

java.lang.Object

com.yahoo.searchlib.rankingexpression.transform.ExpressionTransformer<CONTEXT>

Direct Known Subclasses:

ConstantDereferencer, Simplifier, TensorMaxMinTransformer

public abstract class ExpressionTransformer<CONTEXT extends TransformContext>
extends Object

Superclass of expression transformers. The scope (lifetime) of a transformer instance is a single compilation of all the expressions in one rank profile.

Author:

bratseth

Constructor Summary

Constructors

Constructor	Description
ExpressionTransformer()

Method Summary

Modifier and Type	Method	Description
RankingExpression	transform(RankingExpression expression, CONTEXT context)
abstract ExpressionNode	transform(ExpressionNode node, CONTEXT context)	Transforms an expression node and returns the transformed node.
protected CompositeNode	transformChildren(CompositeNode node, CONTEXT context)	Utility method which calls transform on each child of the given node and return the resulting transformed composite

Methods inherited from class java.lang.Object

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

Constructor Details

ExpressionTransformer

public ExpressionTransformer()

Method Details

transform

public RankingExpression transform(RankingExpression expression,
 CONTEXT context)

transform

public abstract ExpressionNode transform(ExpressionNode node,
 CONTEXT context)

Transforms an expression node and returns the transformed node. This ic called with the root node of an expression to transform by clients of transformers. Transforming nested expression nodes are left to each transformer.

transformChildren

protected CompositeNode transformChildren(CompositeNode node,
 CONTEXT context)

Utility method which calls transform on each child of the given node and return the resulting transformed composite