自定義DWR攔截器

使用DWR和其它mvc框架混用時(如struts和springmvc)，不會經過struts和springmvc的攔截器，如果有需求，需要自定義一個dwr攔截器。 

dwr.xml配置如下

<dwr>
    <allow>
        <filter class="com.twl.util.DWRFilter"></filter>
    </allow>
</dwr>

DWRFilter.java 
由於doFilter沒有提供HttpServletRequest的參數，所以獲取request需要使用WebContextFactory去獲取 

package com.twl.util;
 
import java.lang.reflect.Method;
 
import javax.servlet.Filter;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
 
import org.directwebremoting.AjaxFilter;
import org.directwebremoting.AjaxFilterChain;
import org.directwebremoting.WebContextFactory;
 
import com.twl.core.framework.constant.UserConstant;
import com.twl.core.framework.user.UserSessionInfo;
import com.twl.core.framework.util.ContextContainer;
 
/**
 * DWR過濾器
 * 
 * @version 1.0
 * @author Quinn He
 * @date 2013-6-4
 */
public class DWRFilter implements AjaxFilter {
 
    /**
     * @see Filter#destroy()
     */
    public void destroy() {
    }
 
    /**
     * @see Filter#init(FilterConfig)
     */
    public void init(FilterConfig fConfig) throws ServletException {
    }
 
    @Override
    public Object doFilter(Object arg0, Method arg1, Object[] arg2,
            AjaxFilterChain arg3) throws Exception {
        final HttpServletRequest request = WebContextFactory.get().getHttpServletRequest(); //獲取request對象
        final UserSessionInfo userInfo=(UserSessionInfo) request.getSession().getAttribute(UserConstant.USER_SESSION_INFO);
        ContextContainer.setCurrentLoginUser(userInfo);
        return arg3.doFilter(arg0, arg1, arg2);
    }
 
}