springboot 項目 ,突然在@Component注解下@Autowired的類為null的情況,也就是沒注入成功,或者說是此類在bean加載之前就被調用了。
以下是解決辦法:
編寫工具類實現ApplicationContextAware接口,重寫setApplicationContext方法
@Component
public class SpringContextUtil implements ApplicationContextAware {
private static ApplicationContext applicationContext; // Spring應用上下文環境
/*
* 實現了ApplicationContextAware 接口,必須實現該方法;
* 通過傳遞applicationContext參數初始化成員變量applicationContext
*/
@Override
public void setApplicationContext(ApplicationContext applicationContext)
throws BeansException {
SpringContextUtil.applicationContext = applicationContext;
}
public static ApplicationContext getApplicationContext() {
return applicationContext;
}
@SuppressWarnings("unchecked")
public static <T> T getBean(String name) throws BeansException {
return (T) applicationContext.getBean(name);
}
public static <T> T getBean(Class<T> clazz) throws BeansException {
return (T) applicationContext.getBean(clazz);
}
}
調用方式:
在無法引入的類中,通過beanName引入
public RedisConfig getRedisConfig() { return SpringContextUtil.getBean("redisConfig"); }