/*

  * 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 org.apache.myfaces.taglib.core;

 import javax.el.ELContext;

 import javax.el.ValueExpression;

 import javax.faces.application.Application;

 import javax.faces.application.FacesMessage;

 import javax.faces.component.StateHolder;

 import javax.faces.component.UIComponent;

 import javax.faces.context.FacesContext;

 import javax.faces.validator.Validator;

 import javax.faces.validator.ValidatorException;

 /**

  * This class is used in conjunction with ValidatorImplTag. 

  * 

  * When a tag like this is in a jsp page:

  * 

  * <f:validator binding="#{mybean}"/>

  *  

  *  or

  *  

  * <f:validator validatorId="#{'anyid'}" binding="#{mybean}"/>

  * 

  * The value of mybean could be already on the context, so this

  * converter avoid creating a new variable and use the previous one.

  *

  * @author Leonardo Uribe (latest modification by $Author$)

  * @version $Revision$ $Date$

  *

  */

 public class DelegateValidator implements Validator, StateHolder

 {

     private ValueExpression _validatorId;

     private ValueExpression _binding;

     private String _validatorIdString = null;

     public DelegateValidator()

     {

     }

     public DelegateValidator(ValueExpression id, ValueExpression binding, String converterIdString)

     {

         super();

         _validatorId = id;

         _binding = binding;

         _validatorIdString = converterIdString;

     }

     public boolean isTransient()

     {

         return false;

     }

     public void restoreState(FacesContext facesContext, Object state)

     {

         Object[] values = (Object[]) state;

         _validatorId = (ValueExpression) values[0];

         _binding = (ValueExpression) values[1];

         _validatorIdString = (String) values[2];

     }

     public Object saveState(FacesContext facesContext)

     {

         Object[] values = new Object[3];

         values[0] = _validatorId;

         values[1] = _binding;

         values[2] = _validatorIdString;

         return values;

     }

     public void setTransient(boolean arg0)

     {

         // Do nothing        

     }

     private Validator _getDelegate()

     {

         return _createValidator();

     }

     private Validator _createValidator()

     {

         FacesContext facesContext = FacesContext.getCurrentInstance();

         ELContext elContext = facesContext.getELContext();

         if (null != _binding)

         {

             Object validator;

             try

             {

                 validator = _binding.getValue(elContext);

             }

             catch (Exception e)

             {

                 throw new ValidatorException(new FacesMessage("Error while creating the Validator"), e);

             }

             if (validator instanceof Validator)

             {

                 return (Validator) validator;

             }

         }

         Application application = facesContext.getApplication();

         Validator validator = null;

         try

         {

             // first check if an ValidatorId was set by a method

             if (null != _validatorIdString)

             {

                 validator = application.createValidator(_validatorIdString);

             }

             else if (null != _validatorId)

             {

                 String validatorId = (String) _validatorId.getValue(elContext);

                 validator = application.createValidator(validatorId);

             }

         }

         catch (Exception e)

         {

             throw new ValidatorException(new FacesMessage("Error while creating the Validator"), e);

         }

         if (null != validator)

         {

             if (null != _binding)

             {

                 _binding.setValue(elContext, validator);

             }

             return validator;

         }

         throw new ValidatorException(new FacesMessage("validatorId and/or binding must be specified"));

     }

     public void validate(FacesContext facesContext, UIComponent component, Object value)

             throws ValidatorException

     {

         _getDelegate().validate(facesContext, component, value);

     }

 }