获取web项目中的webroot目录路径

@Override
public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub
logger.info("======begin web context====");
ServletContext context=arg0.getServletContext();
String webroot=context.getContextPath()+"/WebContent/";
context.setAttribute("webroot", webroot);
logger.info("webroot:"+webroot);

}