大家帮帮看看这段代码的是不是有逻辑问题
String   Sql   =   "select   *   from   LoginPwd   where   Name= "+   " ' "+jTextField.getText()+ " ' ";
  ResultSet   rs   =   st.executeQuery(Sql);
  while(rs.next())
  {
  if(jTextField.getText().equals(rs.getString( "Name ").trim())   &&   jTextField1.getText().equals(rs.getString( "Password ").trim()))
  {
  JOptionPane.showMessageDialog(null, "welcome ");
  break;
  }
  else
  {
  JOptionPane.showMessageDialog(null,   "wrong   account/password ");
  break;
  }
  }


我数据库有两个账号kaka,edison密码都是123
我输进去会不会有问题,另外我随便输入字符没有反应,请问一下是什么原因.!




------解决方案--------------------
//SQL查询返回结果集对象
public ResultSet SqlSelect(String sqlstr) {
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(sqlstr);
} catch (SQLException ex) {
ex.printStackTrace();
rs = null;
}
return rs;
}


//验证用户是否存在
public boolean is(String sqlstr) {
rs = SqlSelect(sqlstr);
try {
if (rs.next()) {
return true;
}
return false;

} catch (SQLException ex) {
ex.printStackTrace();
return false;
}
}