spring框架业务上获取IOC容器原理及使用

墨蓝 2022-10-16 02:53 87阅读 0赞

1、业务启动时获取容器，核心代码：

/**
     * @author wanghuainan
     * @date 2020/12/10 15:24
     */
    @Component //启动时扫描
    public class BeanHelper implements ApplicationContextAware {
        private static ApplicationContext applicationContext;
    
        public static <T> T getBeanClass(Class<T> clazz){
            if(Objects.isNull(applicationContext)){
                throw new NullPointerException("Spring容器上下文未初始化");
            }
            return applicationContext.getBean(clazz);
        }
    
        // Object getBean(String var1) throws BeansException;通过对象类型获取
        public static Object getServiceBeanClass(String serviceType){
            if(Objects.isNull(applicationContext)){
                throw new NullPointerException("Spring容器上下文未初始化");
            }
            return applicationContext.getBean(serviceType);
        }
    
    
        //启动服务时初始化获取容器
        @Override
        public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
            this.applicationContext = applicationContext;
        }
    
    }

2、业务方法通过容器获取初始化好的对象

RelationService relationService = (RelationService) BeanHelper.getServiceBeanClass(relationModel.getRelationType());

3、启动时DEBUG 断点验证初始化

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25hbmRhbzE1OA_size_16_color_FFFFFF_t_70][]

4、使用场景

一般策略模式或者工厂模式使用

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