無法從 mysql 獲取要在我的 jList 中顯示的數據

Question

無法從 mysql 獲取要在我的 jList 中顯示的數據。 數據將使用 system.out.println 命令顯示在控制台中，因此我知道我的數據庫連接良好。 這是我正在嘗試使用的代碼部分......

public class NewJFrame extends javax.swing.JFrame 
{

{

String dbData;
//String dbUrl = "jdbc:mysql://your.database.domain/yourdatabasename";
String dbUrl = "jdbc:mysql://localhost:3306/movedb?autoReconnect=true&useSSL=false";
//String dbClass = "com.mysql.jdbc.Driver";
String query = "SELECT PID, + FirstName, + LastName FROM patientlist";
try 
{
    String selectQuery = "SELECT PID, + FirstName, + LastName FROM patientlist";
    Class.forName("com.mysql.cj.jdbc.Driver");
    Connection con = DriverManager.getConnection (dbUrl, "root", "Menace12!");
    Statement stmt = con.createStatement();
    ResultSet rs = stmt.executeQuery(query);
    while (rs.next()) 
    {
        dbData = rs.getString(1) + ", " +  rs.getString(3) + ", " +  rs.getString(2);
        System.out.println(dbData);
        Object FirstName;
        String LastName;
        String PID;

    }
                  DefaultListModel dlm = new DefaultListModel(); //needed to get the items from our combined string data into the list
     //actually adding stuff to list.
   dlm.addElement("PID" + ", " + "LastName" + " ," + "FirstName"); //adding objects to dlm
    //jList1.setModel(dlm); //setting the objects in dlm to our list.


    con.close();
} //end try
catch(ClassNotFoundException e) 
{
e.printStackTrace();
}
catch(SQLException e) 
{
e.printStackTrace();
}       
}

Answer 1

如果要填充列表，請在while循環內遍歷 resultSet 時執行此操作：

DefaultListModel dlm = new DefaultListModel();
while (rs.next()) {
    dlm.addElement(new StringBuilder("")append(rs.getString("PID")).append(", ")
                   .append(rs.getString("FirstName")).append(", ")
                   .append(ra.getString("LastName")).toString());
    // Providing that "FileName", "LastName", and "PID" are actally
    // the field names within your database table.
}
jList1.setModel(dlm);