springmvc取得Spring管理的bean

1、servlet方式加载时,
【web.xml】

<servlet>  
<servlet-name>springMVC</servlet-name>  
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
<init-param>  
<param-name>contextConfigLocation</param-name>  
<param-value>classpath*:/springMVC.xml</param-value>  
</init-param>  
<load-on-startup>1</load-on-startup>  
</servlet>  

spring容器放在ServletContext中的key是org.springframework.web.servlet.FrameworkServlet.CONTEXT.springMVC
注意后面的springMVC,是你的servlet-name配置的值,注意适时修改。

ServletContext sc=略   
WebApplicationContext attr = (WebApplicationContext)sc.getAttribute("org.springframework.web.servlet.FrameworkServlet.CONTEXT.springMVC");  

2、listener方式加载时:
【web.xml】

<context-param>  
  <param-name>contextConfigLocation</param-name>  
  <param-value>/WEB-INF/applicationContext</param-value>  
</context-param>  
  
<listener>  
  <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
</listener>  

【jsp/servlet】可以这样取得 

ServletContext context = getServletContext();   
WebApplicationContext applicationContext  = WebApplicationContextUtils .getWebApplicationContext(context);   

3、通用的方法来了,神器啊,前的  1、2两种方法并不通用,可以抛弃了。
在配置文件中加入:

<!-- 用于持有ApplicationContext,可以使用SpringContextHolder.getBean('xxxx')的静态方法得到spring bean对象 -->  
<bean class="com.xxxxx.SpringContextHolder" lazy-init="false" /> 
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中取出ApplicaitonContext.  
 *   
 */  
public class SpringContextHolder implements ApplicationContextAware {   
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   
}   
  
/**  
* 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, 自动转型为所赋值对象的类型.  
*/  
@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, 自动转型为所赋值对象的类型.  
*/  
@SuppressWarnings("unchecked")   
public static <T> T getBean(Class<T> clazz) {   
checkApplicationContext();   
return (T) applicationContext.getBeansOfType(clazz);   
}   
  
/**  
* 清除applicationContext静态变量.  
*/  
public static void cleanApplicationContext() {   
applicationContext = null;   
}   
  
private static void checkApplicationContext() {   
if (applicationContext == null) {   
throw new IllegalStateException("applicaitonContext未注入,请在applicationContext.xml中定义SpringContextHolder");   
}   
}   
} 

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转载自blog.csdn.net/huawen6/article/details/89338444