org.apache.commons.scxml.env.jsp
Class ELEvaluator

java.lang.Object
  org.apache.commons.scxml.env.jsp.ELEvaluator

All Implemented Interfaces:

Serializable, Evaluator

public class ELEvaluator
extends Object
implements Evaluator, Serializable

Evaluator implementation enabling use of EL expressions in SCXML documents.

See Also:

Serialized Form

Constructor Summary

ELEvaluator()
Constructor.

ELEvaluator(javax.servlet.jsp.el.FunctionMapper fnMapper)
Constructor for EL evaluator that supports user-defined functions.

Method Summary

Object	eval(Context ctx, String expr) Evaluate an expression.
Boolean	evalCond(Context ctx, String expr) Evaluate a condition.
Node	evalLocation(Context ctx, String expr) Evaluate a location that returns a Node within an XML data tree.
protected javax.servlet.jsp.el.FunctionMapper	getBuiltinFnMapper() Get the FunctionMapper for builtin SCXML/Commons SCXML functions.
protected org.apache.commons.logging.Log	getLog() Get the log used by this Evaluator instance.
Context	newContext(Context parent) Create a new child context.
protected void	setLog(org.apache.commons.logging.Log log) Set the log used by this Evaluator instance.

Methods inherited from class java.lang.Object

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

Constructor Detail

ELEvaluator

public ELEvaluator()

Constructor.

ELEvaluator

public ELEvaluator(javax.servlet.jsp.el.FunctionMapper fnMapper)

Constructor for EL evaluator that supports user-defined functions.

Parameters:

fnMapper - The function mapper for this Evaluator.

See Also:

FunctionMapper

Method Detail

eval

public Object eval(Context ctx,
                   String expr)
            throws SCXMLExpressionException

Evaluate an expression.

Specified by:

eval in interface Evaluator

Parameters:

ctx - variable context

expr - expression

Returns:

a result of the evaluation

Throws:

SCXMLExpressionException - For a malformed expression

See Also:

Evaluator.eval(Context, String)

evalCond

public Boolean evalCond(Context ctx,
                        String expr)
                 throws SCXMLExpressionException

Description copied from interface: Evaluator

Evaluate a condition. Manifests as "cond" attributes of <transition>, <if> and <elseif> elements.

Specified by:

evalCond in interface Evaluator

Parameters:

ctx - variable context

expr - expression

Returns:

true/false

Throws:

SCXMLExpressionException - A malformed exception

See Also:

Evaluator.evalCond(Context, String)

evalLocation

public Node evalLocation(Context ctx,
                         String expr)
                  throws SCXMLExpressionException

Description copied from interface: Evaluator

Evaluate a location that returns a Node within an XML data tree. Manifests as "location" attributes of <assign> element.

Specified by:

evalLocation in interface Evaluator

Parameters:

ctx - variable context

expr - expression

Returns:

The location node.

Throws:

SCXMLExpressionException - A malformed exception

See Also:

Evaluator.evalLocation(Context, String)

newContext

public Context newContext(Context parent)

Create a new child context.

Specified by:

newContext in interface Evaluator

Parameters:

parent - parent context

Returns:

new child context

See Also:

Evaluator.newContext(Context)

setLog

protected void setLog(org.apache.commons.logging.Log log)

Set the log used by this Evaluator instance.

Parameters:

log - The new log.

getLog

protected org.apache.commons.logging.Log getLog()

Get the log used by this Evaluator instance.

Returns:

Log The log being used.

getBuiltinFnMapper

protected javax.servlet.jsp.el.FunctionMapper getBuiltinFnMapper()

Get the FunctionMapper for builtin SCXML/Commons SCXML functions.

Returns:

builtinFnMapper The FunctionMapper