Package org.apache.qpid.server.query.engine.parsing.expression.function.datetime

Class ExtractExpression<T,R>

java.lang.Object

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

org.apache.qpid.server.query.engine.parsing.expression.function.AbstractFunctionExpression<T,java.lang.Number>

org.apache.qpid.server.query.engine.parsing.expression.function.datetime.ExtractExpression<T,R>

Type Parameters:

T - Input parameter type

R - Output parameter type

All Implemented Interfaces:

java.util.function.Function<T,java.lang.Number>, Expression<T,java.lang.Number>, ExpressionNode<T,java.lang.Number>

public class ExtractExpression<T,R>
extends AbstractFunctionExpression<T,java.lang.Number>

The EXTRACT() function extracts a part from a given date.

Field Summary

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

_functionName

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

_metadata

Constructor Summary

Constructors

Constructor	Description
ExtractExpression(java.lang.String alias, java.util.List<ExpressionNode<T,?>> args)	Constructor initializes children expression list

Method Summary

Modifier and Type	Method	Description
java.lang.Number	apply(T value)	Performs extract operation using parameters and the value supplied

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

evaluateChild, getFunctionName, getOptionalConstantParameter, getOptionalParameter, getRequiredParameter

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

containsAggregation, ctx, evaluateChild, getAggregations, getAlias, 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

Methods inherited from interface java.util.function.Function

andThen, compose

Constructor Detail

ExtractExpression

public ExtractExpression(java.lang.String alias,
                         java.util.List<ExpressionNode<T,?>> args)

Constructor initializes children expression list

Parameters:

alias - Expression alias

args - List of children expressions

Method Detail

apply

public java.lang.Number apply(T value)

Performs extract operation using parameters and the value supplied

Parameters:

value - Object to handle

Returns:

Resulting number