多线程访问到过期Session的测试代码

AccessSessionInAnotherThread.java

import org.apache.catalina.Context;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.session.StandardManager;
import org.apache.catalina.startup.Tomcat;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

/**
 *
 * 1. 新建一个maven项目
 * 2. 在pom.xml里添加以下依赖
   <dependency>
     <groupId>org.apache.tomcat.embed</groupId>
     <artifactId>tomcat-embed-core</artifactId>
     <version>7.0.57</version>
   </dependency>
   <dependency>
     <groupId>org.apache.tomcat.embed</groupId>
     <artifactId>tomcat-embed-logging-juli</artifactId>
     <version>7.0.57</version>
   </dependency>
   <dependency>
     <groupId>org.apache.tomcat.embed</groupId>
     <artifactId>tomcat-embed-jasper</artifactId>
     <version>7.0.57</version>
   </dependency>
   <dependency>
     <groupId>org.apache.tomcat.embed</groupId>
     <artifactId>tomcat-embed-el</artifactId>
     <version>7.0.57</version>
   </dependency>
 * 3. 运行这个程序
 * 4. 然后访问 http://localhost:8080/
 * 5. 等待一会儿看控制台输出，会有IllegateStateException抛出
 *
 */
public class AccessSessionInAnotherThread {

  public static void main(String[] args) throws LifecycleException, ServletException {

    Tomcat tomcat = new Tomcat();
    tomcat.getHost().setBackgroundProcessorDelay(1);
    tomcat.setPort(8080);

    Context rootCtx = tomcat.addContext("/", "/");
    tomcat.addServlet("/", "default", new HttpServlet() {
      @Override
      protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        final HttpSession session = req.getSession();
        session.setAttribute("abc", "fsfsdfsdfsdf");
        Thread thread = new Thread(new Runnable() {
          @Override
          public void run() {
            try {
              // 2秒后再尝试访问session
              // attempt to access session after 2 seconds
              Thread.sleep(2000l);
              session.getAttribute("abc");
            } catch (InterruptedException e) {
              e.printStackTrace();
            }
          }
        });
        thread.start();
        resp.getWriter().println("DefaultServlet");
      }
    });
    rootCtx.addServletMapping("/", "default");

    tomcat.start();
    // 设置默认的session 最大非激活间隔时长1秒
    // set session max inactive interval to 1 second
    rootCtx.getManager().setMaxInactiveInterval(1);
    // 设置manager的清理频率，默认是6，这里改成1
    // set session expiring frequence to 1
    ((StandardManager)rootCtx.getManager()).setProcessExpiresFrequency(1);
    tomcat.getServer().await();

  }

}