我一直在寻找这个问题的答案，但还没有找到。
基本上，我试图通过GUI连接到数据库服务器。我的老板希望能够输入所有字段，然后检查它们是否是有效的条目，然后如果有任何无效的条目，他希望我将文本变为红色，表明该字段无效。我有try语句catch ClassNotFoundException和SQLException。因为有多个字段需要检查，所以我尝试使用一组if语句来检查连接信息。下面是代码，希望有意义...

//The cancel boolean values in this code are used elsewhere to regulate the Threads
    try 
    {
                   //attempt connection here
    } 
    catch(ClassNotFoundException | SQLException e)
    {
        String[] errors = new String[4]; //This will create a String array of the errors it catches
                                         //and will later get called into a method that displays
                                         //the messages in a JOptionPane.showMessageDialog()
        if (e.getMessage().startsWith("The TCP/IP connection to the host"))
        {
            errors[0] = "SQL CONNECTION FAILED: Please check the server URL you entered to make sure it is correct.";
            cancel = true;
            mGUI.serverNameTextField.setForeground(Color.RED);
        }

        if (e.getMessage().startsWith("Login failed for user"))
        {
            errors[1] = "LOGIN FAILED: You do not have sufficient access to the server.";
            cancel = true;

        }
        if (e.getMessage().startsWith("Cannot open database"))
        {
            errors[2] = "SQL CONNECTION FAILED: Please check the database name you entered to make sure it is correct.";
            cancel = true;
            mGUI.dbNameTextField.setForeground(Color.RED);
        }

        mGUI.reportErrors(errors); //Method where it reports the String[] array of errors
                                   //However, the 'errors' parameter only returns one error
                                   //message at a time, which is the problem.

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谢谢你的帮助！

• • 我更改了if语句，添加了一个AND参数，用于检查特定的错误代码。您可以通过设置断点并查看调试透视图来查找错误代码，也可以像我所做的那样设置print语句来查看错误代码。下面是print语句：

System.out.println(((SQLException) e).getErrorCode());

型
以下是我的新for语句：

try 
    {
        //attempt connection here
    } 
    catch(SQLException | ClassNotFoundException e)
    {
        if (e instanceof SQLServerException && ((SQLServerException) e).getErrorCode() == 0)
        {
            //code here
        }
        else{
            //code here
        }
        System.out.println(((SQLException) e).getErrorCode()); //Here is the print statement to see the error code.
        if (e instanceof SQLServerException && ((SQLServerException) e).getErrorCode() == 4060)
        {
            //code here
        }else{
            //code here
        }
        if(cancel != true)
        {
            //code here
        }
    }

型