/**
 * Description:
 * SpringContextHolder.java Create on 2013-3-8 上午10:19:20 
 * @author xiaopin
 * @version 1.0
 * Copyright (c) 2013 BMS,Inc. All Rights Reserved.
 */
package com.sv.netty.config;

import org.springframework.context.ApplicationContext;

/**
 * 以静态变量保存Spring ApplicationContext, 可在任何代码任何地方任何时候中取出ApplicaitonContext.
 *
 * @author calvin
 */
public class SpringContextHolder  {

	private static ApplicationContext applicationContext;

	/**
	 * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.
	 */
	public  void setApplicationContext(ApplicationContext applicationContext) {
		SpringContextHolder.applicationContext = applicationContext; // NOSONAR
	}


	/**
	 * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.
	 */
	public static  void setContext(ApplicationContext applicationContext) {
		SpringContextHolder.applicationContext = applicationContext; // NOSONAR
	}
	/**
	 * 取得存储在静态变量中的ApplicationContext.
	 */
	public static ApplicationContext getApplicationContext() {
		checkApplicationContext();
		return applicationContext;
	}

	/**
	 * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋于对象的类
	 */
	@SuppressWarnings("unchecked")
	public static <T> T getBean(String name) {
		checkApplicationContext();
		return (T) applicationContext.getBean(name);
	}

	/**
	 * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋对象的类 如果有多个Bean符合Class, 取出第一个
	 */
	public static <T> T getBean(Class<T> requiredType) {
		checkApplicationContext();
		return SpringContextHolder.applicationContext.getBean(requiredType);
	}

	/**
	 * 清除applicationContext静态变量.
	 */
	public static void cleanApplicationContext() {
		applicationContext = null;
	}

	private static void checkApplicationContext() {
		if (SpringContextHolder.applicationContext == null) {
			throw new IllegalStateException("applicaitonContext未注册请在applicationContext.xml中定义SpringContextHolder");
		}
	}
}
