Spring扩展接口-初始化（@PostConstruct，afterPropertiesset, init-method）

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Spring实例化之后，提供三种初始化的方法：

• 使用JSR-250规范定义的@Postconstruct注解。
• 实现InitializingBean接口，实现afterPropertiesset()方法。
• 使用Spring提供的@Bean init-method标签。

执行顺序：@Postconstruct -> afterPropertiesset -> init-method
示例:

@Service
public class BService implements InitializingBean {

    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("===初始化===");
    }
}

更多信息请移步Spring专栏：www.yuque.com/mrhuang-ire…