com.espertech.esper.epl.expression.ops

Class ExprBetweenNodeImpl

java.lang.Object

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

com.espertech.esper.epl.expression.ops.ExprBetweenNodeImpl

All Implemented Interfaces:

ExprEvaluator, ExprNode, ExprValidator, ExprBetweenNode, MetaDefItem, Serializable

public class ExprBetweenNodeImpl
extends ExprNodeBase
implements ExprEvaluator, ExprBetweenNode

Represents the between-clause function in an expression tree.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ExprBetweenNodeImpl(boolean lowEndpointIncluded, boolean highEndpointIncluded, boolean notBetween) Ctor.

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.
Object	evaluate(EventBean[] eventsPerStream, boolean isNewData, ExprEvaluatorContext exprEvaluatorContext) Evaluate event tuple and return result.
ExprEvaluator	getExprEvaluator()
ExprPrecedenceEnum	getPrecedence() Returns precedence.
Class	getType() Returns the type that the node's evaluate method returns an instance of.
boolean	isConstantResult() Returns true if the expression node's evaluation value doesn't depend on any events data, as must be determined at validation time, which is bottom-up and therefore reliably allows each node to determine constant value.
boolean	isHighEndpointIncluded() Returns true if the high endpoint is included, false if not
boolean	isLowEndpointIncluded() Returns true if the low endpoint is included, false if not
boolean	isNotBetween() Returns true for inverted range, or false for regular (openn/close/half-open/half-closed) ranges.
void	toPrecedenceFreeEPL(StringWriter writer)
ExprNode	validate(ExprValidationContext validationContext)

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

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

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.espertech.esper.epl.expression.core.ExprNode

accept, accept, acceptChildnodes, addChildNode, addChildNodes, getChildNodes, replaceUnlistedChildNode, setChildNode, setChildNodes, toEPL

Constructor Detail

ExprBetweenNodeImpl

public ExprBetweenNodeImpl(boolean lowEndpointIncluded,
                           boolean highEndpointIncluded,
                           boolean notBetween)

Ctor.

Parameters:

lowEndpointIncluded - is true for the regular 'between' or false for "val in (a:b)" (open range), or false if the endpoint is not included

highEndpointIncluded - indicates whether the high endpoint is included

notBetween - is true for 'not between' or 'not in (a:b), or false for a regular between

Method Detail

getExprEvaluator

public ExprEvaluator getExprEvaluator()

Specified by:

getExprEvaluator in interface ExprNode

isConstantResult

public boolean isConstantResult()

Description copied from interface: ExprNode

Returns true if the expression node's evaluation value doesn't depend on any events data, as must be determined at validation time, which is bottom-up and therefore reliably allows each node to determine constant value.

Specified by:

isConstantResult in interface ExprNode

Returns:

true for constant evaluation value, false for non-constant evaluation value

isLowEndpointIncluded

public boolean isLowEndpointIncluded()

Returns true if the low endpoint is included, false if not

Specified by:

isLowEndpointIncluded in interface ExprBetweenNode

Returns:

indicator if endppoint is included

isHighEndpointIncluded

public boolean isHighEndpointIncluded()

Returns true if the high endpoint is included, false if not

Specified by:

isHighEndpointIncluded in interface ExprBetweenNode

Returns:

indicator if endppoint is included

isNotBetween

public boolean isNotBetween()

Returns true for inverted range, or false for regular (openn/close/half-open/half-closed) ranges.

Specified by:

isNotBetween in interface ExprBetweenNode

Returns:

true for not betwene, false for between

validate

public ExprNode validate(ExprValidationContext validationContext)
                  throws ExprValidationException

Specified by:

validate in interface ExprValidator

Throws:

ExprValidationException

getType

public Class getType()

Description copied from interface: ExprEvaluator

Returns the type that the node's evaluate method returns an instance of.

Specified by:

getType in interface ExprEvaluator

Returns:

type returned when evaluated

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.

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

toPrecedenceFreeEPL

public void toPrecedenceFreeEPL(StringWriter writer)

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