servletconverter.java

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/*
 * Copyright 2005 Joe Walker
 *
 * 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.directwebremoting.convert;

import javax.servlet.ServletConfig;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.directwebremoting.WebContext;
import org.directwebremoting.WebContextFactory;
import org.directwebremoting.dwrp.SimpleOutboundVariable;
import org.directwebremoting.extend.Converter;
import org.directwebremoting.extend.InboundContext;
import org.directwebremoting.extend.InboundVariable;
import org.directwebremoting.extend.OutboundContext;
import org.directwebremoting.extend.OutboundVariable;

/**
 * A converter that magics up HTTP objects
 * @author Joe Walker [joe at eireneh dot com]
 * @version $Id: StringConverter.java,v 1.2 2004/11/04 15:54:07 joe_walker Exp $
 */
public class ServletConverter extends BaseV20Converter implements Converter
{
    /* (non-Javadoc)
     * @see org.directwebremoting.Converter#convertInbound(java.lang.Class, org.directwebremoting.InboundVariable, org.directwebremoting.InboundContext)
     */
    public Object convertInbound(Class paramType, InboundVariable iv, InboundContext inctx)
    {
        WebContext webcx = WebContextFactory.get();

        if (HttpServletRequest.class.isAssignableFrom(paramType))
        {
            return webcx.getHttpServletRequest();
        }

        if (HttpServletResponse.class.isAssignableFrom(paramType))
        {
            return webcx.getHttpServletResponse();
        }

        if (ServletConfig.class.isAssignableFrom(paramType))
        {
            return webcx.getServletConfig();
        }

        if (ServletContext.class.isAssignableFrom(paramType))
        {
            return webcx.getServletContext();
        }

        if (HttpSession.class.isAssignableFrom(paramType))
        {
            return webcx.getSession(true);
        }

        return null;
    }

    /* (non-Javadoc)
     * @see org.directwebremoting.Converter#convertOutbound(java.lang.Object, org.directwebremoting.OutboundContext)
     */
    public OutboundVariable convertOutbound(Object data, OutboundContext outctx)
    {
        return new SimpleOutboundVariable("null", outctx, true);
    }
}