java - "The Statement did not return a result set error"怎么解决？

Question

我正在尝试在语句未返回结果集时处理 SQLServerException。我还是 java 的新手，所以我无法找到解决它的方法。请任何人都可以建议我如何解决错误？我遇到困难的地方是当此存储过程不返回任何结果集并且我想显示类似“未找到记录”的内容时。我该如何解决？

stmt = conn.prepareCall("{call p_GetAllowedPublicIPs(?,?,?)}");

---

 @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //processRequest(request, response);
        PrintWriter out = response.getWriter();
        String IsLoginDisabled = null;
         String  BankID =null;
         String publicip=null;
        try {
          //processRequest(request, response);
          Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
          Connection conn = null;
          CallableStatement myStmt = null;
          int count =0;

          conn = DriverManager.getConnection("jdbc:sqlserver://MPESA\\SQL2012;user=realm;password=friend;database=ElmaTest");

          if(conn!=null)
          {
              out.println("Connection Succcesful");
          myStmt = conn.prepareCall("{call sp_GetPortalUser(?,?,?)}");

                myStmt.setString("Country", "Kenya");
                myStmt.setString("BankName", "CS");
                myStmt.setString("UserID", "Frank");

               ResultSet rs= myStmt.executeQuery();
              while(rs.next())       
              {
                  count++;
                  BankID = rs.getString("BankID");
                  String employeeid= rs.getString("EmployeeID");
                  String FirstName = rs.getString("FirstName");
                  String LastName= rs.getString("LastName");
                 String MiddleName = rs.getString("MiddleName");
                 String  Address = rs.getString("Address");
                  String MobileNumber= rs.getString("MobileNumber");
                  String Emailid = rs.getString("EmailID");
                  String TypeofID= rs.getString("TypeOfID");
                 String IDNumber = rs.getString("IDNumber");
                 String ipaddress = rs.getString("IPAddress");
                 IsLoginDisabled = rs.getString("isLoginDisabled");
                 String LoginFailureIPaddress = rs.getString("LoginFailureIPAddress");



                  System.out.println("count"+count);
                  System.out.println("BankID" +BankID);
                  System.out.println("EmployeeId"+employeeid);
                  System.out.println("FirstName"+FirstName);
                  System.out.println("MiddleName"+MiddleName);
                   System.out.println("LastName"+LastName);
                   System.out.println("Address"+Address);
                  System.out.println("MobileNumber"+MobileNumber);
                  System.out.println("EmailId"+Emailid);
                  System.out.println("TypeoFiD"+TypeofID);
                   System.out.println("Idnumber"+IDNumber);
                     System.out.println("ipaddress"+ipaddress);
                  System.out.println("isLoginDisabled"+IsLoginDisabled);
                   System.out.println("LoginFailureIPaddress"+LoginFailureIPaddress);







              }

            if(count>0)
              {
                  int logindisabled = Integer.valueOf(IsLoginDisabled);
                  CallableStatement stmt = null;
                  if (logindisabled!=1)
                  {
                      try {
                          stmt = conn.prepareCall("{call p_GetAllowedPublicIPs(?,?,?)}");
                      } catch (SQLException ex) {
                          Logger.getLogger(LoginController.class.getName()).log(Level.SEVERE, null, ex);
                      }
                   stmt.setString("Country", "Kenya");
                   stmt.setString("BankID", "99");
                   stmt.setString("PublicIP", "1");
                  ResultSet rp = stmt.executeQuery();
                  //  System.out.println(rp.next());
                  while(rp.next())
                  {
                      String ipaddress = rp.getString("IPAddress");
                      System.out.println("ipaddress"+ipaddress);
                  }



                  }
          }





        }
      } catch (ClassNotFoundException | SQLException ex) {
          Logger.getLogger(Search.class.getName()).log(Level.SEVERE, null, ex);
      }









    }

Answer 1

事实上，您的程序没有引发任何异常，没有结果也不异常(exception)。

您可以使用 CallableStatement 的 execute() 方法。 execute 方法将返回一个 boolean 值，指示是否存在与您的请求执行对应的 ResultSet。

Javadoc 链接:https://docs.oracle.com/javase/7/docs/api/java/sql/PreparedStatement.html#execute()

仍然可以通过父类(super class)Statement: https://docs.oracle.com/javase/7/docs/api/java/sql/Statement.html#getResultSet()的getResultSet方法获取ResultSet

在您的情况下，您将执行以下操作:

boolean gotResults = myStmt.execute();
ResultSet rs = null;
if(!gotResults){
   System.out.println("No results returned");
} else {
   rs = myStmt.getResultSet();
}