Spring上下文信息获取简单实现

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我们经常会在工作中需要获取Spring上下文信息，来获取程序中的一些要素，以下就是一个简单的获取Spring上下文的简单实现。

public class SpringContextHolder implements ApplicationContextAware {

    private static ApplicationContext applicationContext;

    public void setApplicationContext(ApplicationContext applicationContext) {
        SpringContextHolder.applicationContext = applicationContext;
    }

    /**
     * 得到Spring 上下文环境
     * 
     * @return
     */
    public static ApplicationContext getApplicationContext() {
        checkApplicationContext();
        return applicationContext;
    }

    /**
     * 通过Spring Bean name 得到Bean
     * 
     * @param name bean 上下文定义名称
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) {
        checkApplicationContext();
        return (T) applicationContext.getBean(name);
    }

    /**
     * 通过类型得到Bean
     * 
     * @param clazz
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(Class<T> clazz) {
        checkApplicationContext();
        return (T) applicationContext.getBeansOfType(clazz);
    }

    private static void checkApplicationContext() {
        if (applicationContext == null) {
            throw new IllegalStateException("applicaitonContext未注入,请在application-context.xml中定义SpringContextHolder");
        }
    }

}

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public abstract interface ApplicationContextAware extends Aware {
    public abstract void setApplicationContext(
            ApplicationContext paramApplicationContext) throws BeansException;
}

public abstract interface Aware {
}