使用if语句判断用户注册时是否填写了用户名和密码结果报错
直接点击注册会跳转到
@WebServlet(name = "RegisterServlet", urlPatterns = "/Register")
public class RegisterServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//解决网页乱码问题
response.setContentType("text/html;charset=utf-8");
request.setCharacterEncoding("utf-8");
response.setCharacterEncoding("utf-8");//设置编码
String name = request.getParameter("name");
String pwd = request.getParameter("pwd");
String pwd2 = request.getParameter("pwd2");
PrintWriter out = response.getWriter();
if(pwd==null&&pwd2==null) {
if (pwd.equals(pwd2)){
try {
Database database=new Database();
database.insert(name,pwd);
out.println("注册成功");
ArrayListusedata=database.getAlluser();
out.println("请返回登陆界面"+"返回登入");
} catch (ClassNotFoundException e) {
e.printStackTrace();
out.println("注册失败");
} catch (SQLException throwables) {
throwables.printStackTrace();
out.println("注册失败2");
}
}else {
out.println("两次输入的密码不一致");
out.println("请返注册页面"+"返回注册");
}
}else {
out.println("请输入密码");
out.println("请返注册页面"+"返回注册");
}
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request,response);
}
}
应该是else 里面的内容和try 弄混了,但是我该怎么改?
1 灰色的那个是因为那个变量没有在任何地方使用,所以IDEA 会这样灰色显示提示你
2 后面那个判断你写错了 if (pwd == null && pwd2 == null) 这个按照你的代码逻辑实际上应该是 if (pwd != null && pwd2 != null)