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

Class ExprPreviousNode

java.lang.Object

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

com.espertech.esper.common.internal.epl.expression.prev.ExprPreviousNode

All Implemented Interfaces:

ExprEnumerationEval, ExprEnumerationForge, ExprEvaluator, ExprForge, ExprForgeInstrumentable, ExprNode, ExprNodeRenderable, ExprValidator

public class ExprPreviousNode
extends ExprNodeBase
implements ExprEvaluator, ExprEnumerationForge, ExprEnumerationEval, ExprForgeInstrumentable

Represents the 'prev' previous 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
ExprPreviousNode(ExprPreviousNodePreviousType previousType)

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 codegenMethodScope, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
CodegenExpression	evaluateCodegenUninstrumented(EPTypeClass requiredType, CodegenMethodScope codegenMethodScope, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
EventBean	evaluateGetEventBean(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
CodegenExpression	evaluateGetEventBeanCodegen(CodegenMethodScope parent, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
Collection<EventBean>	evaluateGetROCollectionEvents(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
CodegenExpression	evaluateGetROCollectionEventsCodegen(CodegenMethodScope parent, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
Collection	evaluateGetROCollectionScalar(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext context)
CodegenExpression	evaluateGetROCollectionScalarCodegen(CodegenMethodScope parent, ExprForgeCodegenSymbol exprSymbol, CodegenClassScope codegenClassScope)
EPTypeClass	getComponentTypeCollection()
Integer	getConstantIndexNumber()
EPTypeClass	getEvaluationType()
EventType	getEventTypeCollection(StatementRawInfo statementRawInfo, StatementCompileTimeServices compileTimeServices)
EventType	getEventTypeSingle(StatementRawInfo statementRawInfo, StatementCompileTimeServices compileTimeServices)
ExprEvaluator	getExprEvaluator()
ExprEnumerationEval	getExprEvaluatorEnumeration()
ExprForge	getForge()
ExprForgeConstantType	getForgeConstantType()
ExprNode	getForgeRenderable()
ExprPrecedenceEnum	getPrecedence()	Returns precedence.
ExprPreviousNodePreviousType	getPreviousType()
EPTypeClass	getResultType()
int	getStreamNumber()
boolean	isConstantIndex()
boolean	isConstantResult()
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

ExprPreviousNode

public ExprPreviousNode(ExprPreviousNodePreviousType previousType)

Method Details

getExprEvaluator

public ExprEvaluator getExprEvaluator()

Specified by:

getExprEvaluator in interface ExprForge

getForgeConstantType

public ExprForgeConstantType getForgeConstantType()

Specified by:

getForgeConstantType in interface ExprForge

getStreamNumber

public int getStreamNumber()

getConstantIndexNumber

public Integer getConstantIndexNumber()

isConstantIndex

public boolean isConstantIndex()

getResultType

public EPTypeClass getResultType()

getForge

public ExprForge getForge()

Specified by:

getForge in interface ExprNode

getExprEvaluatorEnumeration

public ExprEnumerationEval getExprEvaluatorEnumeration()

Specified by:

getExprEvaluatorEnumeration in interface ExprEnumerationForge

getEvaluationType

public EPTypeClass getEvaluationType()

Specified by:

getEvaluationType in interface ExprForge

validate

public ExprNode validate(ExprValidationContext validationContext)
                  throws ExprValidationException

Specified by:

validate in interface ExprValidator

Throws:

ExprValidationException

getPreviousType

public ExprPreviousNodePreviousType getPreviousType()

isConstantResult

public boolean isConstantResult()

evaluateGetROCollectionEvents

public Collection<EventBean> evaluateGetROCollectionEvents(EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

evaluateGetROCollectionEvents in interface ExprEnumerationEval

evaluateGetEventBean

public EventBean evaluateGetEventBean(EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

evaluateGetEventBean in interface ExprEnumerationEval

evaluateGetROCollectionScalar

public Collection evaluateGetROCollectionScalar(EventBean[] eventsPerStream,
 boolean isNewData,
 ExprEvaluatorContext context)

Specified by:

evaluateGetROCollectionScalar in interface ExprEnumerationEval

evaluateGetROCollectionEventsCodegen

public CodegenExpression evaluateGetROCollectionEventsCodegen(CodegenMethodScope parent,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateGetROCollectionEventsCodegen in interface ExprEnumerationForge

evaluateGetEventBeanCodegen

public CodegenExpression evaluateGetEventBeanCodegen(CodegenMethodScope parent,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateGetEventBeanCodegen in interface ExprEnumerationForge

evaluateGetROCollectionScalarCodegen

public CodegenExpression evaluateGetROCollectionScalarCodegen(CodegenMethodScope parent,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateGetROCollectionScalarCodegen in interface ExprEnumerationForge

getEventTypeCollection

public EventType getEventTypeCollection(StatementRawInfo statementRawInfo,
 StatementCompileTimeServices compileTimeServices)
                                 throws ExprValidationException

Specified by:

getEventTypeCollection in interface ExprEnumerationForge

Throws:

ExprValidationException

getEventTypeSingle

public EventType getEventTypeSingle(StatementRawInfo statementRawInfo,
 StatementCompileTimeServices compileTimeServices)
                             throws ExprValidationException

Specified by:

getEventTypeSingle in interface ExprEnumerationForge

Throws:

ExprValidationException

getComponentTypeCollection

public EPTypeClass getComponentTypeCollection()
                                       throws ExprValidationException

Specified by:

getComponentTypeCollection in interface ExprEnumerationForge

Throws:

ExprValidationException

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 codegenMethodScope,
 ExprForgeCodegenSymbol exprSymbol,
 CodegenClassScope codegenClassScope)

Specified by:

evaluateCodegenUninstrumented in interface ExprForgeInstrumentable

evaluateCodegen

public CodegenExpression evaluateCodegen(EPTypeClass requiredType,
 CodegenMethodScope codegenMethodScope,
 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 ExprEnumerationForge

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