顯示到JTable的

Question

我想用JTable 當我輸入客戶ID，然後再上我要到同一個窗口或另一個窗口的客戶的所有細節壓上顯示特定客戶詳細Java頁面特定用戶的數據？

怎麼辦？我嘗試使用下面的代碼，但失敗。

import java.awt.BorderLayout; 
import java.awt.Container; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.sql.*; 
import java.util.Vector; 
import java.util.logging.Level; 
import java.util.logging.Logger; 
import javax.swing.*; 
import javax.swing.table.DefaultTableModel; 

public abstract class Bill extends JFrame implements ActionListener 
{ 
JTextField textFieldId; 
JLabel l1; 
JLabel l2; 
    JButton b2; 
Container c = getContentPane(); 
    ResultSet rs1 = null;   
    DefaultTableModel dtm = new DefaultTableModel(); 

Bill() 
{ 
    super("Shree Datta Digambar"); 
    setBounds(140,250,777,555); 
    c.setLayout(null); 
    textFieldId = new JTextField(); 
    l1 = new JLabel("New Customer Entry :-"); 
    l2 = new JLabel("Customer Id"); 
    l1.setBounds(10,10,340,20); 
    l2.setBounds(10,20,140,70);  
    textFieldId.setBounds(10,70,70,20);    
    b2 = new JButton("Ok");  
    b2.setBounds(10,160,50,20);   
    c.add(b2); 
    c.add(l1); 
    c.add(l2); 
    c.add(textFieldId);     
      setVisible(true); 
    setDefaultCloseOperation(EXIT_ON_CLOSE);     
      b2.addActionListener(this); 
} 
    public static void main(String[] args) 
    { 
     Bill bc=new Bill() {}; 
    } 
    public void actionPerformed(ActionEvent e) 
     { 

      System.out.println("You clicked the button");     
      if(e.getSource()==b2) 
      { 
       try 
       { 
        Connection con; 
      try { 
       Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); 
      } catch (ClassNotFoundException ex) { 
       Logger.getLogger(Bill.class.getName()).log(Level.SEVERE, null, ex); 
      } 
      con =DriverManager.getConnection("jdbc:odbc:devendra");      
        java.sql.Statement st = con.createStatement(); 
        PreparedStatement ps = con.prepareStatement(null); 
        ps=con.prepareStatement("SELECT FROM Customer 
              where Customer_Id = ?"); 
        rs1 = ps.executeQuery(); 
        while(rs1.next()) 
        { 
         dtm.addRow(new Object[]{ 
      rs1.getString(1),rs1.getString(2),rs1.getInt(3),rs1.getString(4) }); 
        } 
       JOptionPane.showMessageDialog(null,"You successfully Enter the Entry"); 
       } 
      catch (SQLException s) 
        { 
         System.out.println("SQL code does not execute."); 
       JOptionPane.showMessageDialog(null,"Please Enter the Detail Correctly"); 
        }   
      } 
     }} 

Answer 1

有很多事情，我可以看到，不會幫助你。

1. Bill是abstract。沒有理由是abstract。
2. 沒有JTable。這實際上是非常令人驚訝的，因爲你有一個實際的TableModel
3. 你正在使用null佈局。這永遠不會幫助你。
4. 您正在從JFrame延伸。這不是一個好主意，因爲它會立即阻止您以其他形式重新使用此課程。
5. 您的查詢不會將任何值綁定到變量參數。
6. 你的異常處理極不理想一點點...

一種更好的方法可能看起來像......

import java.awt.BorderLayout; 
import java.awt.EventQueue; 
import java.awt.event.ActionEvent; 
import java.awt.event.ActionListener; 
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 
import java.sql.SQLException; 
import javax.swing.JButton; 
import javax.swing.JFrame; 
import javax.swing.JLabel; 
import javax.swing.JOptionPane; 
import javax.swing.JPanel; 
import javax.swing.JScrollPane; 
import javax.swing.JTable; 
import javax.swing.JTextField; 
import javax.swing.UIManager; 
import javax.swing.UnsupportedLookAndFeelException; 
import javax.swing.table.DefaultTableModel; 

public class TestTable { 

    public static void main(String[] args) { 
     new TestTable(); 
    } 

    public TestTable() { 
     EventQueue.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       try { 
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName()); 
       } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) { 
       } 

       JFrame frame = new JFrame("Testing"); 
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
       frame.setLayout(new BorderLayout()); 
       frame.add(new Bill()); 
       frame.pack(); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 
    } 

    public class Bill extends JPanel implements ActionListener { 

     JTextField textFieldId; 
     JLabel l1; 
     JLabel l2; 
     JButton b2; 
     ResultSet rs1 = null; 
     DefaultTableModel dtm = new DefaultTableModel(); 

     public Bill() { 
      setLayout(new BorderLayout()); 

      JPanel fields = new JPanel(); 

      textFieldId = new JTextField(10); 
      l1 = new JLabel("New Customer Entry :-"); 
      l2 = new JLabel("Customer Id"); 
      b2 = new JButton("Ok"); 

      fields.add(l2); 
      fields.add(textFieldId); 
      fields.add(b2); 

      add(fields, BorderLayout.NORTH); 

      b2.addActionListener(this); 

      // Don't forget to add a table. 
      add(new JScrollPane(new JTable(dtm))); 

     } 

     public void actionPerformed(ActionEvent e) { 

      System.out.println("You clicked the button"); 
      if (e.getSource() == b2) { 
       PreparedStatement ps = null; 
       try { 
        Connection con; 
        Class.forName("sun.jdbc.odbc.JdbcOdbcDriver"); 
        con = DriverManager.getConnection("jdbc:odbc:devendra"); 
        ps = con.prepareStatement("SELECT FROM Customer where Customer_Id = ?"); 
        // You must bind the parameter with a value... 
        ps.setString(1, textFieldId.getText()); 
        rs1 = ps.executeQuery(); 
        while (rs1.next()) { 
         dtm.addRow(new Object[]{ 
          rs1.getString(1), rs1.getString(2), rs1.getInt(3), rs1.getString(4)}); 
        } 
        JOptionPane.showMessageDialog(null, "You successfully Enter the Entry"); 
       } catch (SQLException s) { 
        System.out.println("SQL code does not execute."); 
        s.printStackTrace(); 
        JOptionPane.showMessageDialog(null, "Please Enter the Detail Correctly"); 
       } catch (Exception exp) { 
        exp.printStackTrace(); 
        JOptionPane.showMessageDialog(this, "Failed to perform query: " + exp.getMessage()); 
       } finally { 

        try { 
         ps.close(); 
        } catch (Exception ex) { 
        } 

       } 
      } 
     } 
    } 
} 

我想你可能要花費多讀一點點時間...

• Creating a UI with Swing
• How to use tables
• JDBC Database Access