Springboot普通类如何获取bean实例?

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private JWTConfig jwtConfig=null;
    public JWTConfig getJWTConfig(){
        if(jwtConfig==null){
        	//根据类名获取
            jwtConfig = SpringContextUtil.getBeanByClass(JWTConfig.class);
        }
        return jwtConfig;
    }

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@Component
public class SpringContextUtil implements ApplicationContextAware {

    private static ApplicationContext applicationContext;


    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        SpringContextUtil.applicationContext = applicationContext;
    }

    /**
     * 获得spring上下文
     * @return ApplicationContext spring上下文
     */
    public static ApplicationContext getApplicationContext(){
        return applicationContext;
    }

    /***
     * 根据一个bean的id获取配置文件中相应的bean
     */
    public static Object getBean(String beanId) throws BeansException {
        if (applicationContext.containsBean(beanId)) {
            return applicationContext.getBean(beanId);
        }
        return null;
    }

    /***
     * 根据一个bean的类型获取配置文件中相应的bean
     */
    public static <T> T getBeanByClass(Class<T> requiredType) throws BeansException {
        return applicationContext.getBean(requiredType);
    }

    /**
     * 如果BeanFactory包含一个与所给名称匹配的bean定义，则返回true
     */
    public static boolean containsBean(String name) {
        return applicationContext.containsBean(name);
    }
}