com.espertech.esper.common.internal.epl.expression.funcs

Class ExprCoalesceNode

java.lang.Object

com.espertech.esper.common.internal.epl.expression.core.ExprNodeBase

com.espertech.esper.common.internal.epl.expression.funcs.ExprCoalesceNode

All Implemented Interfaces:

ExprNode, ExprNodeRenderable, ExprValidator, Serializable

public class ExprCoalesceNode
extends ExprNodeBase

Represents the COALESCE(a,b,...) function is an expression tree.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ExprCoalesceNode()

Method Summary

Modifier and Type	Method and Description
boolean	equalsNode(ExprNode node, boolean ignoreStreamPrefix) Return true if a expression node semantically equals the current node, or false if not.
ExprEvaluator	getExprEvaluator()
ExprForge	getForge()
ExprPrecedenceEnum	getPrecedence() Returns precedence.
boolean	isConstantResult()
void	toPrecedenceFreeEPL(StringWriter writer)
ExprNode	validate(ExprValidationContext validationContext)

Methods inherited from class com.espertech.esper.common.internal.epl.expression.core.ExprNodeBase

accept, accept, acceptChildnodes, addChildNode, addChildNodes, addChildNodeToFront, checkValidated, checkValidatedException, getChildNodes, replaceUnlistedChildNode, setChildNode, setChildNodes, toEPL

Methods inherited from class java.lang.Object

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

Constructor Detail

ExprCoalesceNode

public ExprCoalesceNode()

Method Detail

getExprEvaluator

public ExprEvaluator getExprEvaluator()

getForge

public ExprForge getForge()

validate

public ExprNode validate(ExprValidationContext validationContext)
                  throws ExprValidationException

Throws:

ExprValidationException

isConstantResult

public boolean isConstantResult()

toPrecedenceFreeEPL

public void toPrecedenceFreeEPL(StringWriter writer)

Specified by:

toPrecedenceFreeEPL in class ExprNodeBase

getPrecedence

public ExprPrecedenceEnum getPrecedence()

Description copied from interface: ExprNode

Returns precedence.

Returns:

precedence

equalsNode

public boolean equalsNode(ExprNode node,
                          boolean ignoreStreamPrefix)

Description copied from interface: ExprNode

Return true if a expression node semantically equals the current node, or false if not.

Concrete implementations should compare the type and any additional information that impact the evaluation of a node.

Parameters:

node - to compare to

ignoreStreamPrefix - when the equals-comparison can ignore prefix of event properties

Returns:

true if semantically equal, or false if not equals