org.apache.commons.scxml.env.jexl
Class JexlEvaluator

java.lang.Object
  org.apache.commons.scxml.env.jexl.JexlEvaluator

All Implemented Interfaces:

java.io.Serializable, Evaluator

public class JexlEvaluator
extends java.lang.Object
implements Evaluator, java.io.Serializable

Evaluator implementation enabling use of JEXL expressions in SCXML documents.

See Also:

Serialized Form

Constructor Summary

JexlEvaluator()
Constructor.

Method Summary

java.lang.Object	eval(Context ctx, java.lang.String expr) Evaluate an expression.
java.lang.Boolean	evalCond(Context ctx, java.lang.String expr) Evaluate a condition.
org.w3c.dom.Node	evalLocation(Context ctx, java.lang.String expr) Evaluate a location that returns a Node within an XML data tree.
Context	newContext(Context parent) Create a new child context.

Methods inherited from class java.lang.Object

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

Constructor Detail

JexlEvaluator

public JexlEvaluator()

Constructor.

Method Detail

eval

public java.lang.Object eval(Context ctx,
                             java.lang.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 java.lang.Boolean evalCond(Context ctx,
                                  java.lang.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 org.w3c.dom.Node evalLocation(Context ctx,
                                     java.lang.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)