Package org.apache.taglibs.standard.lang.support

Class ExpressionEvaluatorManager

java.lang.Object

org.apache.taglibs.standard.lang.support.ExpressionEvaluatorManager

public class ExpressionEvaluatorManager
extends java.lang.Object

A conduit to the JSTL EL. Based on...

An implementation of the ExpressionEvaluatorManager called for by the JSTL rev1 draft. This class is responsible for delegating a request for expression evaluating to the particular, "active" ExpressionEvaluator for the given point in the PageContext object passed in.

Field Summary

Fields

Modifier and Type	Field	Description
private static ExpressionEvaluator	EVALUATOR
static java.lang.String	EVALUATOR_CLASS
private static Logger	logger
private static java.util.concurrent.ConcurrentMap<java.lang.String,ExpressionEvaluator>	nameMap

Constructor Summary

Constructors

Constructor	Description
ExpressionEvaluatorManager()

Method Summary

Modifier and Type	Method	Description
static java.lang.Object	coerce(java.lang.Object value, java.lang.Class classe)	Performs a type conversion according to the EL's rules.
static java.lang.Object	evaluate(java.lang.String attributeName, java.lang.String expression, java.lang.Class expectedType, javax.servlet.jsp.PageContext pageContext)	Invokes the evaluate() method on the "active" ExpressionEvaluator for the given pageContext.
static java.lang.Object	evaluate(java.lang.String attributeName, java.lang.String expression, java.lang.Class expectedType, javax.servlet.jsp.tagext.Tag tag, javax.servlet.jsp.PageContext pageContext)	Invokes the evaluate() method on the "active" ExpressionEvaluator for the given pageContext.
static ExpressionEvaluator	getEvaluatorByName(java.lang.String name)	Deprecated.
static java.lang.String	validate(java.lang.String attributeName, java.lang.String expression)	Validates an expression.

Methods inherited from class java.lang.Object

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

Field Detail

EVALUATOR_CLASS

public static final java.lang.String EVALUATOR_CLASS

See Also:

Constant Field Values

EVALUATOR

private static final ExpressionEvaluator EVALUATOR

nameMap

private static final java.util.concurrent.ConcurrentMap<java.lang.String,ExpressionEvaluator> nameMap

logger

private static final Logger logger

Constructor Detail

ExpressionEvaluatorManager

public ExpressionEvaluatorManager()

Method Detail

evaluate

public static java.lang.Object evaluate(java.lang.String attributeName,
                                        java.lang.String expression,
                                        java.lang.Class expectedType,
                                        javax.servlet.jsp.tagext.Tag tag,
                                        javax.servlet.jsp.PageContext pageContext)
                                 throws javax.servlet.jsp.JspException

Invokes the evaluate() method on the "active" ExpressionEvaluator for the given pageContext.

Throws:

javax.servlet.jsp.JspException

evaluate

public static java.lang.Object evaluate(java.lang.String attributeName,
                                        java.lang.String expression,
                                        java.lang.Class expectedType,
                                        javax.servlet.jsp.PageContext pageContext)
                                 throws javax.servlet.jsp.JspException

Invokes the evaluate() method on the "active" ExpressionEvaluator for the given pageContext.

Throws:

javax.servlet.jsp.JspException

getEvaluatorByName

@Deprecated
public static ExpressionEvaluator getEvaluatorByName(java.lang.String name)
                                              throws javax.servlet.jsp.JspException

Deprecated.

Gets an ExpressionEvaluator from the cache, or seeds the cache if we haven't seen a particular ExpressionEvaluator before.

Throws:

javax.servlet.jsp.JspException

coerce

public static java.lang.Object coerce(java.lang.Object value,
                                      java.lang.Class classe)
                               throws javax.servlet.jsp.JspException

Performs a type conversion according to the EL's rules.

Throws:

javax.servlet.jsp.JspException

validate

public static java.lang.String validate(java.lang.String attributeName,
                                        java.lang.String expression)

Validates an expression.

Parameters:

attributeName - the name of the attribute containing the expression

expression - the expression to validate

Returns:

null an error message or null of the expression is valid