spring synchronizeOnSession example #Java

to run this synchronizeOnSession example:

set adapter.setSynchronizeOnSession(true) in MyPostProcessor
run http://localhost:8080/sleep
run http://localhost:8080/xxx
then xxx will wait for sleep wake up!

or test the synchronizeOnSession = false

set adapter.setSynchronizeOnSession(false) in MyPostProcessor
run http://localhost:8080/sleep
run http://localhost:8080/xxx
then xxx will NOT wait for sleep wake up!

DemoApplication.java

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportResource;

@SpringBootApplication
@Configuration
@ImportResource("servlet-context.xml")
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

HelloWorldController.java

package com.example.demo;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.tomcat.util.http.parser.Cookie;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 *  * Spring Boot HelloWorld.  synchronizeOnSession example
 */
@RestController
public class HelloWorldController {
    @RequestMapping(value = "/{param}")
    public String sayHello(@PathVariable String param, HttpServletRequest request, HttpSession session) {
        System.out.println("param=" + param);

        Object id = session.getId();
        if (id == null) {
            System.out.println("session not exist " + id);
            //session.setAttribute("p", p);
        } else {
            System.out.println("session existed ，id=" + id);
            if (param.equals("sleep")) {
                try {
                    Thread.sleep(15000);
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                System.out.println("wake up!");
            }
        }
        return "Hello,World! " + param;
    }
}

MyPostProcessor.java

package com.example.demo;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter;

@Component
public class MyPostProcessor implements BeanPostProcessor {
    @Override
    public Object postProcessBeforeInitialization(Object bean, String name) throws BeansException {
        if (bean instanceof RequestMappingHandlerAdapter) {
            RequestMappingHandlerAdapter adapter = (RequestMappingHandlerAdapter) bean;
            adapter.setSynchronizeOnSession(true);
        }

        return bean;
    }

    @Override
    public Object postProcessAfterInitialization(Object bean, String beanName) throws BeansException {
        return bean;
    }
}

servlet-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <context:property-placeholder
        location="classpath:*.properties" />
    <context:component-scan
        base-package="com.example.demo.MyPostProcessor" />

</beans>

details ref: https://github.com/siumennel/demo
https://dzone.com/articles/creating-a-spring-boot-project-with-eclipse-and-ma