org.apache.taglibs.standard.lang.jstl
Class Evaluator

java.lang.Object
  extended by org.apache.taglibs.standard.lang.jstl.Evaluator
All Implemented Interfaces:
ExpressionEvaluator

public class Evaluator
extends Object
implements ExpressionEvaluator

This is the expression evaluator "adapter" that customizes it for use with the JSP Standard Tag Library. It uses a VariableResolver implementation that looks up variables from the PageContext and also implements its implicit objects. It also wraps ELExceptions in JspExceptions that describe the attribute name and value causing the error.

Version:
$Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: tcfujii $
Author:
Nathan Abramson - Art Technology Group, Shawn Bayern

Constructor Summary
Evaluator()
           
 
Method Summary
 Object evaluate(String pAttributeName, String pAttributeValue, Class pExpectedType, Tag pTag, PageContext pPageContext)
          Conduit to old-style call for convenience.
 Object evaluate(String pAttributeName, String pAttributeValue, Class pExpectedType, Tag pTag, PageContext pPageContext, Map functions, String defaultPrefix)
          Evaluates the expression at request time
static String parseAndRender(String pAttributeValue)
          Parses the given attribute value, then converts it back to a String in its canonical form.
 String validate(String pAttributeName, String pAttributeValue)
          Translation time validation of an attribute value.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Evaluator

public Evaluator()
Method Detail

validate

public String validate(String pAttributeName,
                       String pAttributeValue)
Translation time validation of an attribute value. This method will return a null String if the attribute value is valid; otherwise an error message.

Specified by:
validate in interface ExpressionEvaluator

evaluate

public Object evaluate(String pAttributeName,
                       String pAttributeValue,
                       Class pExpectedType,
                       Tag pTag,
                       PageContext pPageContext,
                       Map functions,
                       String defaultPrefix)
                throws JspException
Evaluates the expression at request time

Throws:
JspException

evaluate

public Object evaluate(String pAttributeName,
                       String pAttributeValue,
                       Class pExpectedType,
                       Tag pTag,
                       PageContext pPageContext)
                throws JspException
Conduit to old-style call for convenience.

Specified by:
evaluate in interface ExpressionEvaluator
Throws:
JspException

parseAndRender

public static String parseAndRender(String pAttributeValue)
                             throws JspException
Parses the given attribute value, then converts it back to a String in its canonical form.

Throws:
JspException


Copyright © 2007 Mort Bay Consulting. All Rights Reserved.