普通java类在Tomcat启动时获取ServletContext

1、web.xml配置文件

<context-param>
　　<param-name>messagePrefix</param-name>
　　<param-value>需要在tomcat启动时获取的字符串</param-value>
</context-param>

2、普通java类

 1 import org.springframework.web.context.ContextLoader;
 2 import org.springframework.web.context.WebApplicationContext;
 3 
 4 public class WebConfig{
 5     
 6     /**
 7      * 获取web文件中配置的参数
 8      * paramName参数名称
 9      * */
10     public static String getWebConfig(String paramName){
11         WebApplicationContext wac = ContextLoader.getCurrentWebApplicationContext();
12         String param = "";
13         param = wac.getServletContext().getInitParameter(paramName);
14         if(param==null||"".equals(param)||"null".equals(param)){
15             param="";
16         }
17         return param;
18     }
19 
20 }