VirtualUserInterceptor.java

package com.sp2p.system.interceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;
import com.shove.vo.HelpMessage;
import com.shove.web.action.BaseAction;
import com.sp2p.constants.IConstants;
import com.sp2p.system.exception.FrontHelpMessageException;

/**
 * 前台登录跳转
 * 
 * @author 杨程
 * @Create Jun 3, 2011
 * 
 */
public class VirtualUserInterceptor implements Interceptor {
	public static Log log = LogFactory.getLog(VirtualUserInterceptor.class);
	private static final long serialVersionUID = 1L;
	private HttpServletRequest request;
	private HttpServletResponse response;
	
	public void destroy() {
	}

	public void init() {
	}

	public String intercept(ActionInvocation invocation) throws Exception {
		request = ServletActionContext.getRequest();
		response = ServletActionContext.getResponse();
		String result;
		try {
			result = invocation.invoke();
		} catch (FrontHelpMessageException e) {
			BaseAction action = (BaseAction) invocation.getAction();
			HelpMessage helpMessage = action.getHelpMessage();
			request.getSession().setAttribute("helpMessage", helpMessage);
			if (isAjaxRequest()) {
				response.getWriter().print(IConstants.FRONTPAGEJUMP);
				return null;
			} else {
				return IConstants.FRONTPAGEJUMP;
			}
		}
		return result;
	}
	private boolean isAjaxRequest() {
		String header = request.getHeader("X-Requested-With");
		if (header != null && "XMLHttpRequest".equals(header)){
			return true;
		}
		return false;
	}
	
}