/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License.  You may obtain a copy of the License at

  *

  *   http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied.  See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package javax.faces.validator;

 import javax.el.ELException;

 import javax.el.MethodExpression;

 import javax.faces.application.FacesMessage;

 import javax.faces.component.StateHolder;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 /**

  * see Javadoc of <a href="http://java.sun.com/j2ee/javaserverfaces/1.2/docs/api/index.html">JSF Specification</a>

  *

  * @author Stan Silvert

  */

 public class MethodExpressionValidator implements Validator, StateHolder {

     private MethodExpression methodExpression;

     private boolean isTransient = false;

     /** Creates a new instance of MethodExpressionValidator */

     public MethodExpressionValidator() {

     }

     public MethodExpressionValidator(MethodExpression methodExpression) {

         if (methodExpression == null) throw new NullPointerException("methodExpression can not be null.");

         this.methodExpression = methodExpression;

     }

     public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {

         Object[] params = new Object[3];

         params[0] = context;

         params[1] = component;

         params[2] = value;

         try {

             methodExpression.invoke(context.getELContext(), params);

         } 

         catch (ELException e) {

             Throwable cause = e.getCause();

             if (cause instanceof ValidatorException) {

                 throw (ValidatorException) cause;

             }

             else {

                 throw e;

             }

         }

     }

     public void restoreState(FacesContext context, Object state) {

         methodExpression = (MethodExpression)state;

     }

     public Object saveState(FacesContext context) {

         return methodExpression;

     }

     public void setTransient(boolean newTransientValue) {

         isTransient = newTransientValue;

     }

     public boolean isTransient() {

         return isTransient;

     }

 }