org.apache.cocoon.forms.expression
Class IsNullFunction

java.lang.Object
  org.outerj.expression.AbstractExpression
      org.apache.cocoon.forms.expression.IsNullFunction

All Implemented Interfaces:

org.outerj.expression.Expression

public class IsNullFunction

extends org.outerj.expression.AbstractExpression

Returns true if argument is null.

Version:

$Id: IsNullFunction.html 1304280 2012-03-23 11:18:01Z ilgrosso $

Field Summary

Fields inherited from class org.outerj.expression.AbstractExpression

arguments, column, line

Constructor Summary

IsNullFunction()

Method Summary

void	check()
Object	evaluate(org.outerj.expression.ExpressionContext context)
String	getDescription()
Class	getResultType()

Methods inherited from class org.outerj.expression.AbstractExpression

addArgument, addArgument, checkArgument, checkArguments, checkArgumentsOfSameType, checkNoArguments, getColumn, getLine, setPosition

Methods inherited from class java.lang.Object

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

Constructor Detail

IsNullFunction

public IsNullFunction()

Method Detail

evaluate

public Object evaluate(org.outerj.expression.ExpressionContext context)
                throws org.outerj.expression.ExpressionException

Throws:

org.outerj.expression.ExpressionException

check

public void check()
           throws org.outerj.expression.ExpressionException

Throws:

org.outerj.expression.ExpressionException

getResultType

public Class getResultType()

getDescription

public String getDescription()