自定义DWR拦截器

使用DWR和其它mvc框架混用时(如struts和springmvc)，不会经过struts和springmvc的拦截器，如果有需求，需要自定义一个dwr拦截器。

dwr.xml配置如下

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

DWRFilter.java
由于doFilter没有提供HttpServletRequest的参数，所以获取request需要使用WebContextFactory去获取

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过滤器
 * 
 * @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(); //获取request对象
		final UserSessionInfo userInfo=(UserSessionInfo) request.getSession().getAttribute(UserConstant.USER_SESSION_INFO);
		ContextContainer.setCurrentLoginUser(userInfo);
		return arg3.doFilter(arg0, arg1, arg2);
	}

}