org.josef.web.jsf.util

Class JsfExpressionUtil

java.lang.Object

org.josef.web.jsf.util.JsfExpressionUtil

public final class JsfExpressionUtil
extends Object

Java Server Faces Utility class related to expression handling.

Version:

1.0 $Revision: 5257 $

Author:

Kees Schotanus

Method Summary

Modifier and Type	Method and Description
static javax.faces.event.MethodExpressionActionListener	createMethodExpressionActionListener(String stringMethodExpression) Creates a MethodExpressionActionListener from the supplied stringMethodExpression.
static javax.el.ValueExpression	createValueExpression(String expression, Class<?> expectedType) Creates a value expression, where the expression uses the "Unified Expression Language".
static <T> T	evaluateExpressionCall(String expression, Class<T> expectedReturnType, Class<?>[] parameterTypes, Object[] parameterValues) Evaluates a method call value expression, where the expression uses the "Unified Expression Language".
static <T> T	evaluateExpressionGet(String expression, Class<T> expectedType) Evaluates a get value expression, where the expression uses the "Unified Expression Language".
static <T> void	evaluateExpressionSet(String expression, Class<T> expectedType, T value) Evaluates a set value expression, where the expression uses the "Unified Expression Language".

Methods inherited from class java.lang.Object

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

Method Detail

createValueExpression

public static javax.el.ValueExpression createValueExpression(String expression,
                                                             Class<?> expectedType)

Creates a value expression, where the expression uses the "Unified Expression Language".

Parameters:

expression - The expression to evaluate.

expectedType - The expected type of the supplied expression.

Returns:

The created value expression.

Throws:

javax.el.ELException - When the supplied expression is invalid.

IllegalArgumentException - When the supplied expression is empty.

NullPointerException - When either the supplied expression or expectedType is null.

evaluateExpressionGet

public static <T> T evaluateExpressionGet(String expression,
                                          Class<T> expectedType)

Evaluates a get value expression, where the expression uses the "Unified Expression Language".
An example of a get value expression is: #{1 + 2}

Type Parameters:

T - Type of the expression.

Parameters:

expression - The expression to evaluate.
The expression should either be enclosed within #{...} or ${...}.

expectedType - The expected type of the supplied expression.

Returns:

The value of the supplied expression.

Throws:

javax.el.ELException - When the supplied expression is invalid.

IllegalArgumentException - When the supplied expression is empty.

NullPointerException - When either the supplied expression or expectedType is null.

evaluateExpressionSet

public static <T> void evaluateExpressionSet(String expression,
                                             Class<T> expectedType,
                                             T value)

Evaluates a set value expression, where the expression uses the "Unified Expression Language".
An example of a set value expression is: #{userSettingsBean.locale}

Type Parameters:

T - Type of the expression.

Parameters:

expression - The expression to evaluate.
The expression should either be enclosed within #{...} or ${...}.

expectedType - The expected type of the supplied expression.

value - The value to set.

Throws:

javax.el.ELException - When the supplied expression is invalid.

IllegalArgumentException - When the supplied expression is empty.

NullPointerException - When either the supplied expression or expectedType is null.

evaluateExpressionCall

public static <T> T evaluateExpressionCall(String expression,
                                           Class<T> expectedReturnType,
                                           Class<?>[] parameterTypes,
                                           Object[] parameterValues)

Evaluates a method call value expression, where the expression uses the "Unified Expression Language".
An example of a method call value expression is:
#{applicationSettingsBean.isSupportedStyleSheet}
Note: It is legal to pass in parameters into the expression.

Type Parameters:

T - Type of the expression.

Parameters:

expression - The method call expression to evaluate.
The expression should either be enclosed within #{...} or ${...}.

expectedReturnType - The expected return type of the called method.

parameterTypes - The parameter types.

parameterValues - The parameter values.

Returns:

The result of evaluating the method call expression.

Throws:

javax.el.ELException - When the supplied expression is invalid.

NullPointerException - When either the supplied expression or expectedReturnType is null.

createMethodExpressionActionListener

public static javax.faces.event.MethodExpressionActionListener createMethodExpressionActionListener(String stringMethodExpression)

Creates a MethodExpressionActionListener from the supplied stringMethodExpression.

Parameters:

stringMethodExpression - The method expression to create a MethodExpressionActionListener from.
For example: "#{beanName.methodName}". The methodName should be an existing method on the named bean that accepts an ActionEvent as a parameter.

Returns:

A MethodExpressionActionListener from the supplied stringMethodExpression.

Throws:

IllegalArgumentException - When the supplied stringMethodExpression is empty.

NullPointerException - When the supplied stringMethodExpression is null.