zkoss/zk

/* ServletPortletDispatcher.java

    Purpose:
        
    Description:
        
    History:
        Tue Jan 17 00:44:46     2006, Created by tomyeh

Copyright (C) 2006 Potix Corporation. All Rights Reserved.

{{IS_RIGHT
    This program is distributed under LGPL Version 2.1 in the hope that
    it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.web.portlet;

import java.io.IOException;
import java.lang.reflect.Method;

import javax.portlet.PortletException;
import javax.portlet.PortletRequest;
import javax.portlet.PortletRequestDispatcher;
import javax.portlet.PortletResponse;
import javax.portlet.RenderRequest;
import javax.portlet.RenderResponse;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;

/**
 * A facade of a RequestDispatch for implementing PortletRequestDispatcher.
 *
 * @author tomyeh
 */
public class ServletPortletDispatcher implements PortletRequestDispatcher {
    private final RequestDispatcher _rd;

    /** Returns a facade instance for the specified dispatcher. */
    public static final PortletRequestDispatcher getInstance(RequestDispatcher rd) {
        if (rd instanceof PortletRequestDispatcher)
            return (PortletRequestDispatcher) rd;
        return new ServletPortletDispatcher(rd);
    }

    private ServletPortletDispatcher(RequestDispatcher rd) {
        if (rd == null)
            throw new IllegalArgumentException("null");
        _rd = rd;
    }

    public void include(RenderRequest request, RenderResponse response) throws PortletException, java.io.IOException {
        try {
            // B60-ZK-1337: issues with RenderHttpServletRequest/RenderHttpServletResponse Wrapper
            //   will cause ServletException: Original SevletRequest or wrapped original ServletRequest
            //       not passed to RequestDispatcher in violation of SRV.8.2 and SRV.14.2.5.1
            if (_rd instanceof PortletRequestDispatcher) {
                ((PortletRequestDispatcher) _rd).include(request, response);
            } else {
                if (request instanceof HttpServletRequest && response instanceof HttpServletResponse) {
                    _rd.include((HttpServletRequest) request, (HttpServletResponse) response);
                } else {
                    Method m = null;

                    HttpServletRequest hreq = null;
                    try {
                        try {
                            m = request.getClass().getMethod("getHttpServletRequest");
                        } catch (NoSuchMethodException ex) {
                            m = request.getClass().getMethod("getRequest");
                        }
                        hreq = (HttpServletRequest) m.invoke(request);
                    } catch (Throwable ex) {
                        // expected
                    }

                    HttpServletResponse hres = null;
                    try {
                        try {
                            m = response.getClass().getMethod("getHttpServletResponse");
                        } catch (NoSuchMethodException ex) {
                            m = response.getClass().getMethod("getResponse");
                        }
                        hres = (HttpServletResponse) m.invoke(response);
                    } catch (Throwable ex) {
                        // expected
                    }

                    // To avoid casting exceptions when strict Servlet 2.5 compliance
                    // is turned off on JBoss/Tomcat servers
                    _rd.include(new HttpServletRequestWrapper(hreq), new HttpServletResponseWrapper(hres));
                }
            }
        } catch (ServletException ex) {
            if (ex.getRootCause() != null) {
                throw new PortletException(ex.getRootCause());
            } else {
                throw new PortletException(ex);
            }
        }
    }

    public void include(PortletRequest request, PortletResponse response) throws PortletException, IOException {
    }

    public void forward(PortletRequest request, PortletResponse response) throws PortletException, IOException {
    }
}