JSP：自定义标签之标签

public class IfTag extends SimpleTagSupport {          private boolean test;            public void setTest(boolean test) {                    this.test = test;          }            @Override          public void doTag() throws JspException, IOException {                    // TODO Auto-generated method stub                    if(test)//如果有EL表达式就会先执行                             this.getJspBody().invoke(null);                    else                             super.doTag();                             } }

<% session.setAttribute("user","mmmm") ;%>       未登陆.              welcome用户已经登录.             ssss

Outputs Hello, World         if         cn.itcast.web.tag.example.IfTag         scriptless                          test                  true                  true