Package org.apache.qpid.server.query.engine.parsing.expression.comparison

Class AbstractComparisonExpression<T,R>

java.lang.Object

org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode<T,R>

org.apache.qpid.server.query.engine.parsing.expression.comparison.AbstractComparisonExpression<T,R>

Type Parameters:

T - Input parameter type

R - Output parameter type

All Implemented Interfaces:

Function<T,R>, Predicate<T>, Expression<T,R>, ExpressionNode<T,R>

Direct Known Subclasses:

BetweenExpression, EqualExpression, GreaterThanExpression, GreaterThanOrEqualExpression, InExpression, IsNullExpression, LessThanExpression, LessThanOrEqualExpression, LikeExpression

public abstract class AbstractComparisonExpression<T,R>
extends AbstractExpressionNode<T,R>
implements Predicate<T>

Parent for comparison expression classes

Field Summary

Fields

Modifier and Type	Field	Description
protected String	_operator	Comparison operator

Fields inherited from class org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode

_metadata

Constructor Summary

Constructors

Constructor	Description
AbstractComparisonExpression(String alias, ExpressionNode<T,?> left, ExpressionNode<T,?> low, ExpressionNode<T,?> high)	Constructor initializes children expression list
AbstractComparisonExpression(List<ExpressionNode<T,?>> children)	Constructor initializes children expression list
AbstractComparisonExpression(ExpressionNode<T,?> left)	Constructor initializes children expression list
AbstractComparisonExpression(ExpressionNode<T,?> left, ExpressionNode<T,?> right)	Constructor initializes children expression list

Method Summary

Modifier and Type	Method	Description
String	getAlias()	Returns expression alias
boolean	test(T value)	Evaluates value to a boolean result

Methods inherited from class org.apache.qpid.server.query.engine.parsing.expression.AbstractExpressionNode

containsAggregation, ctx, evaluateChild, getAggregations, getChild, getChildren, getParent, isAccessor, isInstantlyEvaluable, setAlias, setParent, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.qpid.server.query.engine.parsing.expression.Expression

andThen, apply

Methods inherited from interface java.util.function.Function

andThen, compose

Methods inherited from interface java.util.function.Predicate

and, negate, or

Field Detail

_operator

protected String _operator

Comparison operator

Constructor Detail

AbstractComparisonExpression

public AbstractComparisonExpression(ExpressionNode<T,?> left)

Constructor initializes children expression list

Parameters:

left - Left child expression

AbstractComparisonExpression

public AbstractComparisonExpression(ExpressionNode<T,?> left,
                                    ExpressionNode<T,?> right)

Constructor initializes children expression list

Parameters:

left - Left child expression

right - Right child expression

AbstractComparisonExpression

public AbstractComparisonExpression(String alias,
                                    ExpressionNode<T,?> left,
                                    ExpressionNode<T,?> low,
                                    ExpressionNode<T,?> high)

Constructor initializes children expression list

Parameters:

alias - Expression alias

left - Left child expression

low - Low child expression

high - High child expression

AbstractComparisonExpression

public AbstractComparisonExpression(List<ExpressionNode<T,?>> children)

Constructor initializes children expression list

Parameters:

children - Children expressions

Method Detail

test

public boolean test(T value)

Evaluates value to a boolean result

Specified by:

test in interface Predicate<T>

Parameters:

value - Object to handle

Returns:

Boolean result of value evaluation

getAlias

public String getAlias()

Returns expression alias

Specified by:

getAlias in interface ExpressionNode<T,R>

Overrides:

getAlias in class AbstractExpressionNode<T,R>

Returns:

Expression alias