Java 如何在Struts 2中使用<;s:if>;标签?
我在Struts 2中有一个操作,我想在JSP中使用Java 如何在Struts 2中使用<;s:if>;标签?,java,jsp,struts2,ognl,Java,Jsp,Struts2,Ognl,我在Struts 2中有一个操作,我想在JSP中使用测试条件测试电子邮件ID是空的还是null class EmailAction extends ActionSupport { private ArrayList<Email> emailList; //setter and getters } class Email { private String username; Private String password;
测试条件测试电子邮件ID是空的还是null
class EmailAction extends ActionSupport {
private ArrayList<Email> emailList;
//setter and getters
}
class Email {
private String username;
Private String password;
private String emailId;
//getters and setters
}
class EmailAction扩展了ActionSupport{
私有ArrayList电子邮件列表;
//二传手和接球手
}
班级电子邮件{
私有字符串用户名;
私有字符串密码;
私有字符串emailId;
//接球手和接球手
}
您应该为emailId
<s:if test="emailId == null || emailId == ''">