Package org.apache.vxquery.compiler.rewriter.rules

Class RemoveRedundantBooleanExpressionsRule

java.lang.Object

org.apache.vxquery.compiler.rewriter.rules.AbstractRemoveRedundantTypeExpressionsRule

org.apache.vxquery.compiler.rewriter.rules.RemoveRedundantBooleanExpressionsRule

All Implemented Interfaces:

org.apache.hyracks.algebricks.core.rewriter.base.IAlgebraicRewriteRule

public class RemoveRedundantBooleanExpressionsRule
extends AbstractRemoveRedundantTypeExpressionsRule

The rule searches for where the xquery boolean function is used. When the expressions input is already a boolean value, remove the boolean function.

 Before
 
   plan__parent
   %OPERATOR( $v1 : boolean( \@input_expression ) )
   plan__child
   
   Where treat \@input_expression is known to be a boolean value.
   
 After 
 
   plan__parent
   %OPERATOR( $v1 : \@input_expression )
   plan__child
 

Author:

prestonc

Constructor Summary

Constructors

Constructor	Description
RemoveRedundantBooleanExpressionsRule()

Method Summary

Modifier and Type	Method	Description
protected org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier	getSearchFunction()
boolean	hasTypeArgument()
boolean	matchesAllInstancesOf(SequenceType sTypeArg, SequenceType sTypeOutput)

Methods inherited from class org.apache.vxquery.compiler.rewriter.rules.AbstractRemoveRedundantTypeExpressionsRule

rewritePost, rewritePre

Methods inherited from class java.lang.Object

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

Constructor Detail

RemoveRedundantBooleanExpressionsRule

public RemoveRedundantBooleanExpressionsRule()

Method Detail

getSearchFunction

protected org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier getSearchFunction()

Specified by:

getSearchFunction in class AbstractRemoveRedundantTypeExpressionsRule

hasTypeArgument

public boolean hasTypeArgument()

Overrides:

hasTypeArgument in class AbstractRemoveRedundantTypeExpressionsRule

matchesAllInstancesOf

public boolean matchesAllInstancesOf(SequenceType sTypeArg,
                                     SequenceType sTypeOutput)

Specified by:

matchesAllInstancesOf in class AbstractRemoveRedundantTypeExpressionsRule