user != null <br>
</class3g:if>
</span>
处理类
<span style="font-size:16px;">public class MyIfTag extends SimpleTagSupport {
private boolean exp;
public void setExp(boolean exp) {
this.exp = exp;
}
public void doTag() throws JspException, IOException {
if(exp){
JspFragment jf = this.getJspBody();
jf.invoke(null);
