/*
    * 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.context.FacesContext;
  import javax.faces.validator.Validator;
  import javax.faces.webapp.ValidatorELTag;
  import javax.servlet.jsp.JspException;
  
  /**
   * Basic Validator implementation.
   * 
   * @author Andreas Berger (latest modification by $Author$)
   * @version $Revision$ $Date$
   * @since 1.2
   */
  public class ValidatorTag extends ValidatorELTag
  {
      private ValueExpression _validatorId;
      private ValueExpression _binding;
      private String _validatorIdString = null;
  
      public void setValidatorId(ValueExpression validatorId)
      {
          _validatorId = validatorId;
      }
  
      public void setBinding(ValueExpression binding)
      {
          _binding = binding;
      }
  
      /**
       * Use this method to specify the validatorId programmatically.
       * 
       * @param validatorIdString
       */
      public void setValidatorIdString(String validatorIdString)
      {
          _validatorIdString = validatorIdString;
      }
  
      @Override
      public void release()
      {
          super.release();
          _validatorId = null;
          _binding = null;
          _validatorIdString = null;
      }
  
      @Override
      protected Validator createValidator() throws javax.servlet.jsp.JspException
      {
          FacesContext facesContext = FacesContext.getCurrentInstance();
          ELContext elContext = facesContext.getELContext();
          if (null != _binding)
          {
              Object validator;
              try
              {
                  validator = _binding.getValue(elContext);
              }
              catch (Exception e)
              {
                  throw new JspException("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 JspException("Error while creating the Validator", e);
         }
 
         if (null != validator)
         {
             if (null != _binding)
             {
                 _binding.setValue(elContext, validator);
             }
             return validator;
         }
         throw new JspException("validatorId and/or binding must be specified");
     }
 
 }