我需要在我的Java程序中添加表。我使用netbeans GUI来帮助我创建程序。但是当我在其上插入表格时。它不会显示表格。这是我的代码:(请查看方法setTableItemList（））
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package Program;
import java.awt.BorderLayout;
import java.awt.CardLayout;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Date;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableColumn;
import javax.swing.table.TableModel;
import javax.swing.JTable;
public class MainPage extends javax.swing.JFrame {
/**
* Creates new form test
*/
public MainPage() {
initComponents();
}
private Connection connect = null;
private Statement statement = null;
private PreparedStatement preparedStatement = null;
private ResultSet resultSet = null;
private JTable table;
private JScrollPane ScrollPane;
private JPanel topPanel;
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents() {
contentPanel = new javax.swing.JPanel();
jPanel2 = new javax.swing.JPanel();
jLabel2 = new javax.swing.JLabel();
jPanel1 = new javax.swing.JPanel();
jLabel1 = new javax.swing.JLabel();
jLabel3 = new javax.swing.JLabel();
jTextField1 = new javax.swing.JTextField();
jTextField2 = new javax.swing.JTextField();
jLabel4 = new javax.swing.JLabel();
jScrollPane1 = new javax.swing.JScrollPane();
jTextArea1 = new javax.swing.JTextArea();
jButton1 = new javax.swing.JButton();
jPanel3 = new javax.swing.JPanel();
jPanel4 = new javax.swing.JPanel();
jMenuBar1 = new javax.swing.JMenuBar();
jMenu1 = new javax.swing.JMenu();
jMenuItem2 = new javax.swing.JMenuItem();
jMenu2 = new javax.swing.JMenu();
jMenuItem1 = new javax.swing.JMenuItem();
jMenuItem3 = new javax.swing.JMenuItem();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
contentPanel.setLayout(new java.awt.CardLayout());
jLabel2.setText("WELCOME TO .....");
org.jdesktop.layout.GroupLayout jPanel2Layout = new org.jdesktop.layout.GroupLayout(jPanel2);
jPanel2.setLayout(jPanel2Layout);
jPanel2Layout.setHorizontalGroup(
jPanel2Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel2Layout.createSequentialGroup()
.add(144, 144, 144)
.add(jLabel2)
.addContainerGap(166, Short.MAX_VALUE))
);
jPanel2Layout.setVerticalGroup(
jPanel2Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel2Layout.createSequentialGroup()
.add(125, 125, 125)
.add(jLabel2)
.addContainerGap(184, Short.MAX_VALUE))
);
contentPanel.add(jPanel2, "card3");
jLabel1.setText("ID");
jLabel3.setText("Nama");
jTextField1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jTextField1ActionPerformed(evt);
}
});
jLabel4.setText("Keterangan");
jTextArea1.setColumns(20);
jTextArea1.setRows(5);
jScrollPane1.setViewportView(jTextArea1);
jButton1.setText("Submit");
org.jdesktop.layout.GroupLayout jPanel1Layout = new org.jdesktop.layout.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel1Layout.createSequentialGroup()
.add(30, 30, 30)
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.TRAILING)
.add(jButton1)
.add(jPanel1Layout.createSequentialGroup()
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jLabel1)
.add(jLabel3)
.add(jLabel4))
.add(24, 24, 24)
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING, false)
.add(jTextField1)
.add(jTextField2)
.add(jScrollPane1, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, 248, Short.MAX_VALUE))))
.addContainerGap(42, Short.MAX_VALUE))
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel1Layout.createSequentialGroup()
.addContainerGap()
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.BASELINE)
.add(jLabel1)
.add(jTextField1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
.addPreferredGap(org.jdesktop.layout.LayoutStyle.UNRELATED)
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.BASELINE)
.add(jLabel3)
.add(jTextField2, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
.add(18, 18, 18)
.add(jPanel1Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jLabel4)
.add(jScrollPane1, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, 152, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
.add(18, 18, 18)
.add(jButton1)
.addContainerGap(50, Short.MAX_VALUE))
);
contentPanel.add(jPanel1, "card2");
org.jdesktop.layout.GroupLayout jPanel4Layout = new org.jdesktop.layout.GroupLayout(jPanel4);
jPanel4.setLayout(jPanel4Layout);
jPanel4Layout.setHorizontalGroup(
jPanel4Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(0, 400, Short.MAX_VALUE)
);
jPanel4Layout.setVerticalGroup(
jPanel4Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(0, 53, Short.MAX_VALUE)
);
org.jdesktop.layout.GroupLayout jPanel3Layout = new org.jdesktop.layout.GroupLayout(jPanel3);
jPanel3.setLayout(jPanel3Layout);
jPanel3Layout.setHorizontalGroup(
jPanel3Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel4, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
jPanel3Layout.setVerticalGroup(
jPanel3Layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(jPanel3Layout.createSequentialGroup()
.addContainerGap(270, Short.MAX_VALUE)
.add(jPanel4, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.PREFERRED_SIZE))
);
contentPanel.add(jPanel3, "card4");
jMenu1.setText("File");
jMenuItem2.setText("Home");
jMenuItem2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jMenuItem2ActionPerformed(evt);
}
});
jMenu1.add(jMenuItem2);
jMenuBar1.add(jMenu1);
jMenu2.setText("Edit");
jMenuItem1.setText("Item");
jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jMenuItem1ActionPerformed(evt);
}
});
jMenu2.add(jMenuItem1);
jMenuItem3.setText("ItemList");
jMenuItem3.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
jMenuItem3ActionPerformed(evt);
}
});
jMenu2.add(jMenuItem3);
jMenuBar1.add(jMenu2);
setJMenuBar(jMenuBar1);
org.jdesktop.layout.GroupLayout layout = new org.jdesktop.layout.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(org.jdesktop.layout.GroupLayout.TRAILING, contentPanel, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(org.jdesktop.layout.GroupLayout.LEADING)
.add(contentPanel, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, org.jdesktop.layout.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
pack();
}// </editor-fold>
//Edit to see what are you searching
public void readDataBase() throws Exception {
try {
// This will load the MySQL driver, each DB has its own driver
Class.forName("com.mysql.jdbc.Driver");
// Setup the connection with the DB
connect = DriverManager.getConnection("jdbc:mysql://localhost/amp", "root", "root");
// Statements allow to issue SQL queries to the database
statement = connect.createStatement();
// Result set get the result of the SQL query
resultSet = statement
.executeQuery("select * from amp.barang");
//writeResultSet(resultSet);
while (resultSet.next()) {
System.out.println(resultSet.getNString(1));
}
//writeMetaData(resultSet);
// PreparedStatements can use variables and are more efficient
} catch (Exception e) {
throw e;
} finally {
close();
}
}
//Show table + collumns name
private void writeMetaData(ResultSet resultSet) throws SQLException {
// Now get some metadata from the database
// Result set get the result of the SQL query
System.out.println("The columns in the table are: ");
System.out.println("Table: " + resultSet.getMetaData().getTableName(1));
for (int i = 1; i <= resultSet.getMetaData().getColumnCount(); i++) {
System.out.println("Column " + i + " " + resultSet.getMetaData().getColumnName(i));
}
}
//Edit to set in table
private void insertQueryBarang() throws Exception {
try {
// This will load the MySQL driver, each DB has its own driver
Class.forName("com.mysql.jdbc.Driver");
// Setup the connection with the DB
connect = DriverManager.getConnection("jdbc:mysql://localhost/amp", "root", "root");
// Statements allow to issue SQL queries to the database
statement = connect.createStatement();
// Result set get the result of the SQL query
statement
.executeUpdate("INSERT INTO `amp`.`barang` (`idbarang`,`namaBarang`,`keteranganBarang`) "
+ "VALUES ('02','B','this is B')");
//writeResultSet(resultSet);
//writeMetaData(resultSet);
// PreparedStatements can use variables and are more efficient
} catch (Exception e) {
throw e;
} finally {
close();
}
}
//See result
private void writeResultSet(ResultSet resultSet) throws SQLException {
// ResultSet is initially before the first data set
while (resultSet.next()) {
// It is possible to get the columns via name
// also possible to get the columns via the column number
// which starts at 1
// e.g. resultSet.getSTring(2);
String user = resultSet.getString("myuser");
String website = resultSet.getString("webpage");
String summary = resultSet.getString("summary");
Date date = resultSet.getDate("datum");
String comment = resultSet.getString("comments");
System.out.println("User: " + user);
System.out.println("Website: " + website);
System.out.println("Summary: " + summary);
System.out.println("Date: " + date);
System.out.println("Comment: " + comment);
}
}
private void setTableItemList() {
topPanel = new JPanel();
topPanel.setLayout(new BorderLayout());
getContentPane().add(topPanel);
// Create columns names
String columnNames[] = {"Column 1", "Column 2", "Column 3"};
// Create some data
String dataValues[][] = {
{"12", "234", "67"},
{"-123", "43", "853"},
{"93", "89.2", "109"},
{"279", "9033", "3092"}
};
// Create a new table instance
table = new JTable(dataValues, columnNames);
// Add the table to a scrolling pane
ScrollPane = new JScrollPane(table);
topPanel.add(ScrollPane, BorderLayout.CENTER);
jPanel3.add(topPanel);
}
private void close() {
try {
if (resultSet != null) {
resultSet.close();
}
if (statement != null) {
statement.close();
}
if (connect != null) {
connect.close();
}
} catch (Exception e) {
}
}
private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
CardLayout cl = (CardLayout) (contentPanel.getLayout());
cl.show(contentPanel, "card2");
}
private void jMenuItem2ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
CardLayout cl = (CardLayout) (contentPanel.getLayout());
cl.show(contentPanel, "card3");
}
private void jTextField1ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
}
private void jMenuItem3ActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
CardLayout cl = (CardLayout) (contentPanel.getLayout());
cl.show(contentPanel, "card4");
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) throws Exception {
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try {
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (ClassNotFoundException ex) {
java.util.logging.Logger.getLogger(MainPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (InstantiationException ex) {
java.util.logging.Logger.getLogger(MainPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (IllegalAccessException ex) {
java.util.logging.Logger.getLogger(MainPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
} catch (javax.swing.UnsupportedLookAndFeelException ex) {
java.util.logging.Logger.getLogger(MainPage.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
}
//</editor-fold>
/* Create and display the form */
MainPage dao = new MainPage();
//dao.insertQueryBarang();
dao.readDataBase();
dao.setTableItemList();
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new MainPage().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JPanel contentPanel;
private javax.swing.JButton jButton1;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel2;
private javax.swing.JLabel jLabel3;
private javax.swing.JLabel jLabel4;
private javax.swing.JMenu jMenu1;
private javax.swing.JMenu jMenu2;
private javax.swing.JMenuBar jMenuBar1;
private javax.swing.JMenuItem jMenuItem1;
private javax.swing.JMenuItem jMenuItem2;
private javax.swing.JMenuItem jMenuItem3;
private javax.swing.JPanel jPanel1;
private javax.swing.JPanel jPanel2;
private javax.swing.JPanel jPanel3;
private javax.swing.JPanel jPanel4;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JTextArea jTextArea1;
private javax.swing.JTextField jTextField1;
private javax.swing.JTextField jTextField2;
// End of variables declaration
}
答案 0 :(得分：0)
一些事情：
1-如果您正在使用GUI构建器，您可以“直观地”添加该表并通过其表模型填充它。
2-用这种方法：
private void setTableItemList() {
topPanel = new JPanel();
topPanel.setLayout(new BorderLayout());
getContentPane().add(topPanel); // <-- topPanel added for first time
// Create columns names
String columnNames[] = {"Column 1", "Column 2", "Column 3"};
// Create some data
String dataValues[][] = {
{"12", "234", "67"},
{"-123", "43", "853"},
{"93", "89.2", "109"},
{"279", "9033", "3092"}
};
// Create a new table instance
table = new JTable(dataValues, columnNames);
// Add the table to a scrolling pane
ScrollPane = new JScrollPane(table);
topPanel.add(ScrollPane, BorderLayout.CENTER);
jPanel3.add(topPanel); // <-- topPanel added second time to another container
}
您在两个不同的容器中添加topPanel。来自javadoc：
public Component add(Component comp)将指定的组件追加到此容器的末尾。这是 addImpl的便捷方法（java.awt.Component，java.lang.Object， INT）。
此方法更改与布局相关的信息，因此， 使组件层次结构无效。如果容器已经存在 显示后，必须在此后验证层次结构 显示添加的组件。
因此，如果您想将此topPanel直接添加到框架的内容窗格中，请在添加后调用frame.pack()方法。如果您想将topPanel添加到jPanel3，请在添加后调用jPanel3.validate()。