struts2注册问题,能正常跳转，但是数据无法进入数据库

Question

public class RegisterDao {
public boolean hasName(String vip_loginname,String vip_password,String vip_sex){

    Connection conn= ConnectionUtil.getConnection();
    try{
    PreparedStatement pstm=conn.prepareStatement("select * from vip_info where vip_loginname='"+vip_loginname+"'");
    ResultSet rs=pstm.executeQuery();
    if(rs.next()){
        return true;
    }else {
        String sql="insert into vip_info(vip_loginname,vip_password,vip_sex) values ('"+vip_loginname+"','"+vip_password+"','"+vip_sex+"')";
        pstm=conn.prepareStatement(sql);
        pstm.setString(1, vip_loginname);
        pstm.setString(2,vip_password );
        pstm.setString(3, vip_sex);
        int check=pstm.executeUpdate();
        if(check!=0){return false;}
        else return true;
    }

}catch(SQLException e){
    e.printStackTrace();
}

return false;
}

Answer 1

public String execute()throws Exception{
RegisterDao regdao=new RegisterDao();
if(regdao.hasName(vip_loginname,vip_password,vip_sex)){
return "error";
}else return "success";
这是action页面