SpringContextHolder.java工具类

import org.apache.commons.lang3.Validate;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;

/**
 * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候取出ApplicaitonContext.
 * 
 */
//@Service
public class SpringContextHolder implements ApplicationContextAware, DisposableBean {

	private static ApplicationContext applicationContext = null;

	private static Logger logger = LoggerFactory.getLogger(SpringContextHolder.class);

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

	/**
	 * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
	 */
	@SuppressWarnings("unchecked")
	public static  T getBean(String name) {
		assertContextInjected();
		return (T) applicationContext.getBean(name);
	}

	/**
	 * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
	 */
	public static  T getBean(Class requiredType) {
		assertContextInjected();
		return applicationContext.getBean(requiredType);
	}

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

	/**
	 * 实现ApplicationContextAware接口, 注入Context到静态变量中.
	 */
	public void setApplicationContext(ApplicationContext applicationContext) {
//		logger.debug("注入ApplicationContext到SpringContextHolder:{}", applicationContext);

		if (SpringContextHolder.applicationContext != null) {
			logger.warn("SpringContextHolder中的ApplicationContext被覆盖, 原有ApplicationContext为:" + SpringContextHolder.applicationContext);
		}

		SpringContextHolder.applicationContext = applicationContext; // NOSONAR
	}

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

	/**
	 * 检查ApplicationContext不为空.
	 */
	private static void assertContextInjected() {
		Validate.validState(applicationContext != null, "applicaitonContext属性未注入, 请在applicationContext.xml中定义SpringContextHolder.");
	}
}

 

 

 SpringContextUtil.java

 

 
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
 
public class SpringContextUtil implements ApplicationContextAware {
	
  private static ApplicationContext applicationContext;     //Spring应用上下文环境
  
  /**
  * 实现ApplicationContextAware接口的回调方法，设置上下文环境   
  * @param applicationContext
  * @throws BeansException
  */
  public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {	
      SpringContextUtil.applicationContext = applicationContext;
  }
 
  /**
  * @return ApplicationContext
  */
  public static ApplicationContext getApplicationContext() 
   {
    return SpringContextUtil.applicationContext;
  }
 
  /**
  * 获取对象   
  * 
  * @param name
  * @return Object 一个以所给名字注册的bean的实例
  * @throws BeansException
  */
  public static Object getBean(String name) throws BeansException {
	 return applicationContext.getBean(name);
  }
 
  /**
  * 获取类型为requiredType的对象
  * 如果bean不能被类型转换，相应的异常将会被抛出（BeanNotOfRequiredTypeException）
  * @param name       bean注册名
  * @param requiredType 返回对象类型
  * @return Object 返回requiredType类型对象
  * @throws BeansException
  */
  public static Object getBean(String name, Class requiredType) throws BeansException {
    return applicationContext.getBean(name, requiredType);
  }
 
  /**
  * 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 applicationContext.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 NoSuchBeanDefinitionException
  */
  public static boolean isSingleton(String name) throws NoSuchBeanDefinitionException {
    return applicationContext.isSingleton(name);
  }
 
  /**
  * @param name
  * @return Class 注册对象的类型
  * @throws NoSuchBeanDefinitionException
  */
  public static Class getType(String name) throws NoSuchBeanDefinitionException {
    return applicationContext.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 NoSuchBeanDefinitionException
  */
  public static String[] getAliases(String name) throws NoSuchBeanDefinitionException {
    return applicationContext.getAliases(name);
  }
}