添加了session过滤器，判断session是否过期，若过期则添加session过期标识

src/main/java/org/hqu/production_ms/filter/SessionFilter.java

+package org.hqu.production_ms.filter;
+
+import org.apache.shiro.SecurityUtils;
+
+import javax.servlet.*;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+
+/**
+ * created on 2017年5月29日 
+ *
+ * session过滤器，修改response对象，设置session超时标识
+ *
+ * @author  megagao
+ * @version  0.0.1
+ */
+public class SessionFilter implements Filter {
+
+    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException,
+            ServletException {
+
+        HttpServletRequest request = (HttpServletRequest) servletRequest;
+        HttpServletResponse response = (HttpServletResponse) servletResponse;
+        if (!SecurityUtils.getSubject().isAuthenticated()) {
+            //判断session里是否有用户信息,且是否为ajax请求，如果是ajax请求响应头会有，x-requested-with
+            if (request.getHeader("x-requested-with") != null
+                    && request.getHeader("x-requested-with").equalsIgnoreCase("XMLHttpRequest")) {
+                response.setHeader("session-status", "timeout");//在响应头设置session状态
+            }
+        }
+        filterChain.doFilter(request, servletResponse);
+    }
+
+    @Override
+    public void destroy() {
+        // TODO Auto-generated method stub
+    }
+
+    @Override
+    public void init(FilterConfig arg0) throws ServletException {
+        // TODO Auto-generated method stub
+    }
+}