Spring中初始化和销毁方法的执行顺序

Spring中初始化和销毁方法的执行顺序

在Spring中我们可以通过InitializingBean、@PostConstruct、以及制定init-method等方式在bean初始化时做一些初始化相关的 *** 作，以及通过DisposableBean、@PreDestroy和destroy-method等方式在bean销毁时执行一些销毁 *** 作。那么这些不同方式的执行顺序是什么呢？接下来我们通过实战来看下具体的执行顺序。

定义bean

package com.example.demo.service;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;

public class HelloService implements InitializingBean, DisposableBean {

    private String name;

    public HelloService(String name) {
        this.name = name;
    }

    @PostConstruct
    public void postConstruct() {
        System.out.println("PostConstruct name=" + name);
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("InitializingBean name=" + name);
    }

    @Override
    public void destroy() throws Exception {
        System.out.println("DisposableBean name=" + name);
    }

    @PreDestroy
    public void preDestroy() {
        System.out.println("PreDestroy name=" + name);
    }

    public void initMethod() {
        System.out.println("initMethod name=" + name);
    }

    public void destroyMethod() {
        System.out.println("destroyMethod name=" + name);
    }
}

xml中配置bean声明

run项目

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.importResource;

@SpringBootApplication
@importResource(locations = {"classpath:applicationContext.xml"})
public class ArthasDemoApplication {

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

}

执行结果

PostConstruct name=chyang
InitializingBean name=chyang
initMethod name=chyang

PreDestroy name=chyang
DisposableBean name=chyang
destroyMethod name=chyang

结论

• 初始化执行顺序：constructor(构造器) -> PostConstruct -> InitializingBean -> init-method
• 销毁执行顺序：PreDestroy -> DisposableBean -> destroy-method