Spring工具类（获取bean，发布事件）

spring-beans-5.3.1.jar

@Component
public final class SpringUtils implements BeanFactoryPostProcessor{
	
	/**
     * Spring应用上下文环境
     */
    private static ConfigurableListableBeanFactory beanFactory;

	//初始化成员变量
 	@Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        SpringUtils.beanFactory = beanFactory;
    }

	 /**
     * 获取对象
     *
     * @param name
     * @return Object 一个以所给名字注册的bean的实例
     * @throws org.springframework.beans.BeansException
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) throws BeansException {
        return (T) beanFactory.getBean(name);
    }
	
	 /**
     * 获取类型为requiredType的对象
     *
     * @param clz
     * @return
     * @throws org.springframework.beans.BeansException
     */
    public static <T> T getBean(Class<T> clz) throws BeansException {
        T result = (T) beanFactory.getBean(clz);
        return result;
    }

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

    /**
     * 判断以给定名字注册的bean定义是一个singleton还是一个prototype。 如果与给定名字相应的bean定义没有被找到，将会抛出一个异常（NoSuchBeanDefinitionException）
     *
     * @param name
     * @return boolean
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     */
    public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.isSingleton(name);
    }

    /**
     * @param name
     * @return Class 注册对象的类型
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     */
    public static Class<?> getType(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.getType(name);
    }

    /**
     * 如果给定的bean名字在bean定义中有别名，则返回这些别名
     *
     * @param name
     * @return
     * @throws org.springframework.beans.factory.NoSuchBeanDefinitionException
     */
    public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
        return beanFactory.getAliases(name);
    }
}

/**
 * SpringContext
 * @author jack
 */
@Slf4j
@Service
@Lazy(false)
public class SpringContextHolder implements ApplicationContextAware, DisposableBean {
    private static ApplicationContext applicationContext = null;

    /**
     * 取得存储在静态变量中的ApplicationContext.
     */
    public static ApplicationContext getApplicationContext() {
        return applicationContext;
    }

    /**
     * 实现ApplicationContextAware接口, 注入Context到静态变量中.
     */
    @Override
    public void setApplicationContext(ApplicationContext applicationContext) {
        SpringContextHolder.applicationContext = applicationContext;
    }

    /**
     * 清除SpringContextHolder中的ApplicationContext为Null.
     */
    public static void clearHolder() {
        if (log.isDebugEnabled()) {
            log.debug("清除SpringContextHolder中的ApplicationContext:" + applicationContext);
        }
        applicationContext = null;
    }

    /**
     * 发布事件
     *
     * @param event
     */
    public static void publishEvent(ApplicationEvent event) {
        if (applicationContext == null) {
            return;
        }
        applicationContext.publishEvent(event);
    }

    /**
     * 实现DisposableBean接口, 在Context关闭时清理静态变量.
     */
    @Override
    @SneakyThrows
    public void destroy() {
        SpringContextHolder.clearHolder();
    }

    /**
     * 获取运行环境
     * @return
     */
    public static String getActiveProfile() {
        return applicationContext.getEnvironment().getActiveProfiles()[0];
    }

}