trunk/pluto-taglib/src/main/java/org/apache/pluto/tags/DefineObjectsTag.java

/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * 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 org.apache.pluto.tags;

import javax.portlet.PortletConfig;
import javax.portlet.PortletRequest;
import javax.portlet.RenderResponse;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.TagData;
import javax.servlet.jsp.tagext.TagExtraInfo;
import javax.servlet.jsp.tagext.TagSupport;
import javax.servlet.jsp.tagext.VariableInfo;

/**
 * Supporting class for the <CODE>defineObjects</CODE> tag. Creates the
 * following variables to be used in the JSP: <UL> <LI><CODE>renderRequest</CODE>
 * <LI><CODE>renderResponse</CODE> <LI><CODE>portletConfig</CODE> </UL>
 * @see javax.portlet.PortletRequest
 * @see javax.portlet.RenderResponse
 * @see javax.portlet.PortletConfig
 */
public class DefineObjectsTag extends TagSupport {

    /**
     * Processes the <CODE>defineObjects</CODE> tag.
     * @return <CODE>SKIP_BODY</CODE>
     */
    public int doStartTag() throws JspException {
        PortletRequest renderRequest = (PortletRequest) pageContext.getRequest()
            .getAttribute(Constants.PORTLET_REQUEST);
        RenderResponse renderResponse = (RenderResponse) pageContext.getRequest()
            .getAttribute(Constants.PORTLET_RESPONSE);
        PortletConfig portletConfig = (PortletConfig) pageContext.getRequest()
            .getAttribute(Constants.PORTLET_CONFIG);

        if (pageContext.getAttribute("renderRequest") == null)   //Set attributes only once
        {
            pageContext.setAttribute("renderRequest",
                                     renderRequest,
                                     PageContext.PAGE_SCOPE);
        }

        if (pageContext.getAttribute("renderResponse") == null) {
            pageContext.setAttribute("renderResponse",
                                     renderResponse,
                                     PageContext.PAGE_SCOPE);
        }

        if (pageContext.getAttribute("portletConfig") == null) {
            pageContext.setAttribute("portletConfig",
                                     portletConfig,
                                     PageContext.PAGE_SCOPE);
        }

        return SKIP_BODY;
    }

    public static class TEI extends TagExtraInfo {

        public VariableInfo[] getVariableInfo(TagData tagData) {
            VariableInfo[] info = new VariableInfo[]{
                new VariableInfo("renderRequest",
                                 "javax.portlet.PortletRequest",
                                 true,
                                 VariableInfo.AT_BEGIN),
                new VariableInfo("renderResponse",
                                 "javax.portlet.RenderResponse",
                                 true,
                                 VariableInfo.AT_BEGIN),
                new VariableInfo("portletConfig",
                                 "javax.portlet.PortletConfig",
                                 true,
                                 VariableInfo.AT_BEGIN)
            };

            return info;
        }
    }
}