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--笔记

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Spring Bean初始化方法

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Spring Bean初始化及@Bean销毁

  • @PostConstruct
  • @Bean(initMethod = “X”)
  • @InitilizingBean#afterPropertiesSet

@PostConstruct

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@PostConstruct
public void init(){
  System.out.println("PostConstruct init.......");
}

@Bean(initMethod = “X”)

  • 初始化
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/**
* 显式指定bean的名称,初始化调用方法即销毁调用方法
* @return
*/
@Bean(name = "orderBean",initMethod = "init",destroyMethod = "destroy")
public static  OrderAllServiceImpl orderBeanFactory(){
  return new OrderAllServiceImpl();
}
  • 销毁方式-1：在 OrderAllServiceImpl 实现类中写 init 方法和 destroy 方法
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public class OrderAllServiceImpl implements  OrderAllService{
  public void init(){
    log.info("bean init start...");
  }

  @Override
  public List<Product> getProductList(String orderCode) {
    //TODO
    return new ArrayList<>();
  }

  public void destroy(){
    log.info("bean destory...");
  }}
  • 销毁方式-2：使用方法注解 @PostConstruct @PreDestroy
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public class OrderAllServiceImpl implements OrderAllService {
    @PostConstruct
    public void init(){
        System.out.println("bean init");
    }
    @Override
    public List<Product> getProductNameByOrderCode(String code) {
        //TODO
        return new ArrayList<>();
    }
    @PreDestroy
    public void destroy(){
        System.out.println("bean desory");
    }
}

@InitilizingBean#afterPropertiesSet

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@Component
public class OrderProcessors implements InitializingBean {

  @Autowired
  private ApplicationContext applicationContext;

  private static OrderAllService OrderAllService;

  private static final List<OrderProcessor> PROCESSOR_LIST = new ArrayList<>();

  @Autowired
  public void setOrderAllService(OrderAllService OrderAllService) {
    OrderProcessors.OrderAllService = OrderAllService;
  }

  @Override
  public void afterPropertiesSet() throws Exception {
    log.info("init processors");
    // 按顺序添加处理器
    PROCESSOR_LIST.add(applicationContext.getBean(FirstProcessor.class));
    PROCESSOR_LIST.add(applicationContext.getBean(SecondProcessor.class));

  }}

初始化顺序

  • 1.@PostConstruct
  • 2.@InitializingBean#afterPropertiesSet
  • 3.@Bean(initMethod=”X”)

@Bean初始化与销毁方法和 bean 中方法执行的顺序

  • 类的构造函数执行 —》自定义初始化方法执行 —》自定义 destroy 方法 —》 bean 销毁。
来源：

https://github.com/mifunc/Spring-BeanInitialization