/*

  * Copyright 2004-2011 the Seasar Foundation and the Others.

  *

  * Licensed 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.webapp;

 import javax.faces.component.UIComponent;

 import javax.faces.internal.WebAppUtil;

 import javax.servlet.jsp.JspException;

 import javax.servlet.jsp.tagext.TagSupport;

 /**

  * @author shot

  */

 public class AttributeTag extends TagSupport {

     private static final long serialVersionUID = 1L;

     private String name = null;

     private String value = null;

     public AttributeTag() {

     }

     public void setName(String name) {

         this.name = name;

     }

     public void setValue(String value) {

         this.value = value;

     }

     public int doStartTag() throws JspException {

         UIComponentTag componentTag = UIComponentTag

                 .getParentUIComponentTag(pageContext);

         if (componentTag == null) {

             throw new JspException("Not nested in a UIComponentTag");

         }

         UIComponent component = componentTag.getComponentInstance();

         if (component == null) {

             throw new JspException(

                     "No component associated with UIComponentTag");

         }

         String nameObj = name;

         if (UIComponentTag.isValueReference(name)) {

             nameObj = (String) WebAppUtil.getValueFromCreatedValueBinding(name);

         }

         Object valueObj = value;

         if (UIComponentTag.isValueReference(value)) {

             valueObj = WebAppUtil.getValueFromCreatedValueBinding(value);

         }

         if (component.getAttributes().get(nameObj) == null) {

             component.getAttributes().put(nameObj, valueObj);

         }

         return SKIP_BODY;

     }

     public void release() {

         name = null;

         value = null;

     }

 }