@PostConstruct and @PreDestroy in Spring

Spring Framework (24 Part Series)

1 Spring Configuration
2 External Properties in Spring
… 20 more parts…
3 Profiles in Spring
4 Spring Expression Language (SpEL)
5 How Spring implements Singleton Beans
6 Converting explicit into implicit configuration in Spring
7 Autowiring in Spring
8 Lazy Beans in Spring
9 @PostConstruct and @PreDestroy in Spring
10 Stereotype and Meta Annotations in Spring
11 Spring’s FactoryBean Interface
12 The Spring Bean Lifecycle
13 Spring AOP
14 Caching in Spring
15 Spring JDBC
16 Spring Transaction Management
17 JPA with Spring
18 JPA with Spring Boot
19 Spring Web MVC
20 Spring Boot for war
21 Spring MVC REST
22 Reactive Spring Applications
23 Spring Security
24 Spring Injection Types

@PostConstruct adds behavior at startup (after all dependency injection, constructors, and setters) and @PreDestroy adds behavior at shutdown (prior to destroying the bean instance, when a configurable application context is closed and if application shuts down normally. Not called for prototype beans). The annotated methods can have any visibility but must take no parameters and only return void.

@PostConstruct
void populateCache() {
  ...
}

@PreDestroy 
void flushCache() {
  ...
}

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Alternatively, the @Bean annotation has the initMethod and destroyMethod options:

@Bean(initMethod="populateCache", destroyMethod="flushCache")
public Repository repository() {
  ...
}

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原文链接：@PostConstruct and @PreDestroy in Spring