用@Component注解的类中@Autowired为null

编写一个工具类实现ApplicationContextAware接口,重写setApplicationContext方法

@Component
public class ApplicationContextUtils implements ApplicationContextAware {

    private static ApplicationContext context;


    /**
     * Set the ApplicationContext that this object runs in.
     * Normally this call will be used to initialize the object.
     * <p>Invoked after population of normal bean properties but before an init callback such
     * as {@link InitializingBean#afterPropertiesSet()}
     * or a custom init-method. Invoked after {@link ResourceLoaderAware#setResourceLoader},
     *  and
     * {@link MessageSourceAware}, if applicable.
     *
     * @param applicationContext the ApplicationContext object to be used by this object
     * @throws ApplicationContextException in case of context initialization errors
     * @throws BeansException              if thrown by application context methods
     * @see BeanInitializationException
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        context = applicationContext;
    }

    /**
     * 获取bean
     * @param beanName
     * @return
     */
    public static Object getBean(String beanName) {
        return context.getBean(beanName);
    }
}

在需要引入的类中获取bean

public Bean getTemp() {
        return (Bean) ApplicationContextUtils.getBean("temp");
    }

这样就引入进来了,直接调用就可以

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