Package com.espertech.esper.common.internal.epl.expression.prior

Class ExprPriorNode

java.lang.Object

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

com.espertech.esper.common.internal.epl.expression.prior.ExprPriorNode

All Implemented Interfaces:

ExprEvaluator, ExprForge, ExprForgeInstrumentable, ExprNode, ExprNodeRenderable, ExprValidator

public class ExprPriorNode
extends ExprNodeBase
implements ExprEvaluator, ExprForgeInstrumentable

Represents the 'prior' prior event function in an expression node tree.

Field Summary

Fields inherited from interface com.espertech.esper.common.internal.epl.expression.core.ExprEvaluator

EPTYPE, EPTYPEARRAY

Constructor Summary

Constructors

Constructor	Description
ExprPriorNode()

Method Summary

Modifier and Type	Method	Description
boolean	equalsNode(ExprNode node, boolean ignoreStreamPrefix)	Return true if a expression node semantically equals the current node, or false if not.
Object	evaluate(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext)	Evaluate event tuple and return result.
CodegenExpression	evaluateCodegen(EPTypeClass requiredType, CodegenMethodScope parent, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
CodegenExpression	evaluateCodegenUninstrumented(EPTypeClass requiredType, CodegenMethodScope parent, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
int	getConstantIndexNumber()
EPType	getEvaluationType()
ExprEvaluator	getExprEvaluator()
ExprForge	getForge()
ExprForgeConstantType	getForgeConstantType()
ExprNode	getForgeRenderable()
ExprForge	getInnerForge()
ExprPrecedenceEnum	getPrecedence()	Returns precedence.
int	getStreamNumber()
boolean	isConstantResult()
void	setRelativeIndex(int relativeIndex)
void	toPrecedenceFreeEPL(StringWriter writer, ExprNodeRenderableFlags flags)
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 Details

ExprPriorNode

public ExprPriorNode()

Method Details

getExprEvaluator

public ExprEvaluator getExprEvaluator()

Specified by:

getExprEvaluator in interface ExprForge

getStreamNumber

public int getStreamNumber()

getConstantIndexNumber

public int getConstantIndexNumber()

getInnerForge

public ExprForge getInnerForge()

getForge

public ExprForge getForge()

Specified by:

getForge in interface ExprNode

getEvaluationType

public EPType getEvaluationType()

Specified by:

getEvaluationType in interface ExprForge

getForgeConstantType

public ExprForgeConstantType getForgeConstantType()

Specified by:

getForgeConstantType in interface ExprForge

validate

public ExprNode validate(ExprValidationContext validationContext)
                  throws ExprValidationException

Specified by:

validate in interface ExprValidator

Throws:

ExprValidationException

isConstantResult

public boolean isConstantResult()

evaluate

public Object evaluate(EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext exprEvaluatorContext)

Description copied from interface: ExprEvaluator

Evaluate event tuple and return result.

Specified by:

evaluate in interface ExprEvaluator

Parameters:

eventsPerStream - - event tuple

isNewData - - indicates whether we are dealing with new data (istream) or old data (rstream)

exprEvaluatorContext - context for expression evaluation

Returns:

evaluation result, a boolean value for OR/AND-type evalution nodes.

evaluateCodegenUninstrumented

public CodegenExpression evaluateCodegenUninstrumented(EPTypeClass requiredType,
 CodegenMethodScope parent,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateCodegenUninstrumented in interface ExprForgeInstrumentable

evaluateCodegen

public CodegenExpression evaluateCodegen(EPTypeClass requiredType,
 CodegenMethodScope parent,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateCodegen in interface ExprForge

toPrecedenceFreeEPL

public void toPrecedenceFreeEPL(StringWriter writer,
 ExprNodeRenderableFlags flags)

Specified by:

toPrecedenceFreeEPL in class ExprNodeBase

getPrecedence

public ExprPrecedenceEnum getPrecedence()

Description copied from interface: ExprNode

Returns precedence.

Specified by:

getPrecedence in interface ExprNode

Returns:

precedence

getForgeRenderable

public ExprNode getForgeRenderable()

Specified by:

getForgeRenderable in interface ExprForge

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.

Specified by:

equalsNode in interface ExprNode

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

setRelativeIndex

public void setRelativeIndex(int relativeIndex)