com.espertech.esper.epl.expression.visitor

Class ExprNodeSummaryVisitor

java.lang.Object

com.espertech.esper.epl.expression.visitor.ExprNodeSummaryVisitor

All Implemented Interfaces:

ExprNodeVisitor

public class ExprNodeSummaryVisitor
extends Object
implements ExprNodeVisitor

Visitor for compiling usage informaton of special expressions within an expression tree.

Constructor Summary

Constructors

Constructor and Description
ExprNodeSummaryVisitor()

Method Summary

Modifier and Type	Method and Description
String	getMessage() Returns a message if the expression contains special-instruction expressions.
boolean	isHasAggregation()
boolean	isHasPreviousPrior()
boolean	isHasProperties()
boolean	isHasStreamSelect()
boolean	isHasSubselect()
boolean	isPlain() Returns true if the expression is a plain-value expression, without any of the following: properties, aggregation, subselect, stream select, previous or prior
boolean	isVisit(ExprNode exprNode) Allows visitor to indicate whether to visit a given node.
void	visit(ExprNode exprNode) Visit the given expression node.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExprNodeSummaryVisitor

public ExprNodeSummaryVisitor()

Method Detail

isVisit

public boolean isVisit(ExprNode exprNode)

Description copied from interface: ExprNodeVisitor

Allows visitor to indicate whether to visit a given node. Implicitly if a visitor doesn't visit a node it would also not visit any descendent child nodes of that node.

Specified by:

isVisit in interface ExprNodeVisitor

Parameters:

exprNode - is the node in questions

Returns:

true if the visitor wants to visit the child node (next call is visit), or false to skip child

visit

public void visit(ExprNode exprNode)

Description copied from interface: ExprNodeVisitor

Visit the given expression node.

Specified by:

visit in interface ExprNodeVisitor

Parameters:

exprNode - is the expression node to visit

isPlain

public boolean isPlain()

Returns true if the expression is a plain-value expression, without any of the following: properties, aggregation, subselect, stream select, previous or prior

Returns:

true for plain

isHasProperties

public boolean isHasProperties()

isHasAggregation

public boolean isHasAggregation()

isHasSubselect

public boolean isHasSubselect()

isHasStreamSelect

public boolean isHasStreamSelect()

isHasPreviousPrior

public boolean isHasPreviousPrior()

getMessage

public String getMessage()

Returns a message if the expression contains special-instruction expressions.

Returns:

message