org.zkoss.zk.xel.impl
Class SimpleEvaluator

java.lang.Object
  org.zkoss.zk.xel.impl.SimpleEvaluator

All Implemented Interfaces:

java.io.Serializable, Evaluator

Direct Known Subclasses:

BindEvaluatorXImpl

public class SimpleEvaluator
extends java.lang.Object
implements Evaluator

A simple implementation of Evaluator.

Since:

3.0.0

Author:

tomyeh

See Also:

Serialized Form

Constructor Summary

SimpleEvaluator(FunctionMapper mapper, java.lang.Class<? extends ExpressionFactory> expfcls)

Method Summary

java.lang.Object	evaluate(Component comp, Expression expression) Evaluates the expression.
java.lang.Object	evaluate(Page page, Expression expression) Evaluates the expression.
protected ExpressionFactory	getExpressionFactory() Returns the expression factory.
java.lang.Class<? extends ExpressionFactory>	getExpressionFactoryClass() Returns the implementation class of the expression factory, or null to use the default.
FunctionMapper	getFunctionMapper(java.lang.Object ref) Returns the function mapper, or null if not available.
VariableResolver	getVariableResolver(java.lang.Object ref) Returns the variable resolver, or null if not available.
protected XelContext	newXelContext(java.lang.Object ref) Instantiate a XEL context.
Expression	parseExpression(java.lang.String expression, java.lang.Class expectedType) Prepares the expression.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleEvaluator

public SimpleEvaluator(FunctionMapper mapper,
                       java.lang.Class<? extends ExpressionFactory> expfcls)

Parameters:

expfcls - the class that implements the expression factory. If null, the default one is used.

Method Detail

parseExpression

public Expression parseExpression(java.lang.String expression,
                                  java.lang.Class expectedType)
                           throws XelException

Description copied from interface: Evaluator

Prepares the expression.

Specified by:

parseExpression in interface Evaluator

Parameters:

expression - the expression to be prepared for being evaluated later.

expectedType - the expected type of the result of the evaluation

Throws:

XelException

evaluate

public java.lang.Object evaluate(Page page,
                                 Expression expression)
                          throws XelException

Description copied from interface: Evaluator

Evaluates the expression.

Specified by:

evaluate in interface Evaluator

Parameters:

page - the page, or null to ignore

Throws:

XelException

evaluate

public java.lang.Object evaluate(Component comp,
                                 Expression expression)
                          throws XelException

Description copied from interface: Evaluator

Evaluates the expression.

Specified by:

evaluate in interface Evaluator

Parameters:

comp - the component, or null to ignore

Throws:

XelException

getExpressionFactoryClass

public java.lang.Class<? extends ExpressionFactory> getExpressionFactoryClass()

Returns the implementation class of the expression factory, or null to use the default.

getExpressionFactory

protected ExpressionFactory getExpressionFactory()

Returns the expression factory.

newXelContext

protected XelContext newXelContext(java.lang.Object ref)

Instantiate a XEL context. Don't reuse it since it has attributes (that shall not be kept after evaluation).

getFunctionMapper

public FunctionMapper getFunctionMapper(java.lang.Object ref)

Returns the function mapper, or null if not available.

Default: returns the function mapper passed thru SimpleEvaluator(org.zkoss.xel.FunctionMapper, java.lang.Class).

Parameters:

ref - the object,either page, component, or null. It is passed to evaluate(org.zkoss.zk.ui.Page, org.zkoss.xel.Expression)

getVariableResolver

public VariableResolver getVariableResolver(java.lang.Object ref)

Returns the variable resolver, or null if not available.

Default: it returns the variable resolver of the current execution, if any. Otherwise, it returns the current RequestContext, if any. If both not available, null is returned.

Parameters:

ref - the object,either page, component, or null. It is passed to evaluate(org.zkoss.zk.ui.Page, org.zkoss.xel.Expression)