我在Java中创建了一个GUI，它连接MySQL服务器并插入，删除，更新数据。我在此GUI上有一个部分，您可以在文本区域中编写MySQL查询，结果显示在Jtable上。一切正常！我可以打印JTable中的数据或将它们保存到文本文件中！
现在，我想添加另一个功能：当我双击特定单元格时，我想更改JTable的数据，我希望在MySQL表中更新此数据点击一个按钮。
我在互联网上搜索过，但我找不到一个好的例子或一个好的解决方案。我JTable是动态的;这意味着插入了任何查询，数据将显示所需的列名称和数据
以下是代码：
ArrayList columnNames = new ArrayList();
ArrayList data = new ArrayList();
data_connector getdata1 = new data_connector();
host = getdata1.getHost();
username = getdata1.getUsername();
password1 = getdata1.getPassword();
mysql_command = getdata1.getMysql_command();
command_name = getdata1.getCommand_name();
setTitle(command_name);
// Connect to an MySQL Database, run query, get result set
String url = "jdbc:mysql://"+host+":3306/xxxxx";
String userid = username;
String password = password1;
String sql = mysql_command;
// Java SE 7 has try-with-resources
// This will ensure that the sql objects are closed when the program
// is finished with them
try (Connection connection = DriverManager.getConnection( url, userid, password );
Statement stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery( sql ))
{
ResultSetMetaData md = rs.getMetaData();
int columns = md.getColumnCount();
// Get column names
for (int i = 1; i <= columns; i++)
columnNames.add(md.getColumnName(i));
// Get row data
while (rs.next())
{
ArrayList row = new ArrayList(columns);
for (int i = 1; i <= columns; i++)
row.add(rs.getObject(i));
data.add(row);
}
}
catch (SQLException e)
{
System.out.println(e.getMessage());
JOptionPane.showMessageDialog(null, e.getMessage());
mysql_fail_flag = 1;
}
// Create Vectors and copy over elements from ArrayLists to them
// Vector is deprecated but I am using them in this example to keep
// things simple - the best practice would be to create a custom defined
// class which inherits from the AbstractTableModel class
Vector columnNamesVector = new Vector();
Vector dataVector = new Vector();
for (int i = 0; i < data.size(); i++)
{
ArrayList subArray = (ArrayList)data.get(i);
Vector subVector = new Vector();
for (int j = 0; j < subArray.size(); j++)
subVector.add(subArray.get(j));
dataVector.add(subVector);
}
for (int i = 0; i < columnNames.size(); i++ )
columnNamesVector.add(columnNames.get(i));
contentPane.setLayout(null);
// Create table with database data
table = new JTable(dataVector, columnNamesVector)
{
public Class getColumnClass(int column)
{
for (int row = 0; row < getRowCount(); row++)
{
Object o = getValueAt(row, column);
if (o != null)
return o.getClass();
}
return Object.class;
}
};
// table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
JScrollPane scrollPane = new JScrollPane(table);
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
scrollPane.setBounds(5, 5, xframeWidth-20, yframeHeight-70);
getContentPane().add(scrollPane);
JPanel buttonPanel = new JPanel();
buttonPanel.setBounds(5, 856, 1574, 1);
getContentPane().add(buttonPanel);
buttonPanel.setLayout(null);
答案 0 :(得分：0)
在您实际创建JTable的表单中，我不认为这很容易。您要做的是对AbstractTableModel进行子类化，并覆盖setValueAt()方法。你的子类看起来像这样：
class MyModel extends AbstractTableModel
{
private ResultSet result;
private ResultSetMetaData metadata;
public MyModel (ResultSet rs)
{
super();
result = rs; // mustn't be null, maybe check and throw NPE
metadata = result.getMetaData();
}
public int getRowCount ()
{
result.last();
return result.getRow(); // See http://stackoverflow.com/questions/8292256/get-number-of-rows-returned-by-resultset-in-java
}
public int getColumnCount ()
{
return metadata.getColumnCount();
}
public Object getValueAt (int row, int col)
{
result.absolute(row);
return result.getString(col);
}
public String getColumnName (int col)
{
return metadata.getColumnName(col);
}
public void setValueAt (Object value, int row, int col)
{
result.absolute(row);
result.updateObject(col, value);
}
}
我还没有对它进行测试，但您的代码必须如下所示。请注意，您不能关闭Statement，Connection或ResultSet（或创建新的ResultSet，因为某些数据库驱动程序（如MySQL会破坏旧版本）防止任何例外。
答案 1 :(得分：0)
行!!!我设法通过编辑单元格然后按回车来分别更新每个单元格！ 这只适用于1个表，但对我的项目来说还可以！这是代码......
private class RowColumnListSelectionListener implements ListSelectionListener {
public void valueChanged(ListSelectionEvent e) {
rowIndexStart = table.getSelectedRow();
rowIndexEnd = table.getSelectionModel().getMaxSelectionIndex();
colIndexStart = table.getSelectedColumn();
colIndexEnd = table.getColumnModel().getSelectionModel().getMaxSelectionIndex();
for ( i = rowIndexStart; i <= rowIndexEnd; i++) {
for ( j = colIndexStart; j <= colIndexEnd; j++) {
Object cell_value = table.getValueAt(i,j);
Cell_value_string_before = (String) cell_value;
}
}
}
}
public test_table() {
setIconImage(Toolkit.getDefaultToolkit().getImage(test_table.class.getResource("/com/sun/java/swing/plaf/windows/icons/Computer.gif")));
//setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//setBounds(100, 100, 688, 589);
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
xframeWidth = screenSize.width; //dynamic size for frame x-axes
yframeHeight = screenSize.height; //dynamic size for frame y-axes
int xlocation = xframeWidth*2; //dynamic location x-axes
int ylocation = yframeHeight*2; //dynamic location y-axes
setBounds(0,0, xframeWidth, yframeHeight);
setResizable(false);
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu mnNewMenu = new JMenu("Αρχείο");
menuBar.add(mnNewMenu);
JMenuItem mntmNewMenuItem_1 = new JMenuItem("Εξαγωγή σε .txt αρχείο");
mntmNewMenuItem_1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JFileChooser fileChooser =new JFileChooser();
fileChooser.setDialogTitle("Δημιουργία αρχείου .txt");
FileNameExtensionFilter filter = new FileNameExtensionFilter(".txt", "text");
fileChooser.setFileFilter(filter);
int returnVal = fileChooser.showSaveDialog(null);
if (returnVal == JFileChooser.APPROVE_OPTION) {
try {
File file = fileChooser.getSelectedFile();
File newfile = new File(file.getPath()+".txt");
// PrintWriter os = new PrintWriter(file);
FileWriter fw = new FileWriter(newfile,true); //filewriter
BufferedWriter bw = new BufferedWriter(fw); //buffered writer
PrintWriter os = new PrintWriter(bw, true);
os.print("");
for (int col = 0; col < table.getColumnCount(); col++) {
os.print(table.getColumnName(col) + "\t");
os.print(";");
}
os.println("");
os.println("");
for (int row = 0; row < table.getRowCount(); row++) {
for (int col = 0; col < table.getColumnCount(); col++) {
//os.print(table.getColumnName(col) + "\t");
// os.print(": ");
os.print(table.getValueAt(row, col) + "\t");
os.print(";");
// os.print(table.getRowCount() + "\t");
}
os.println("");
}
os.close();
System.out.println("Done!");
}
catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
}
});
mnNewMenu.add(mntmNewMenuItem_1);
JMenuItem mntmNewMenuItem_2 = new JMenuItem("Εκτύπωση");
mntmNewMenuItem_2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
try {
if (! table.print()) {
System.err.println("User cancelled printing");
}
} catch (java.awt.print.PrinterException e1) {
System.err.format("Cannot print %s%n", e1.getMessage());
}
}
});
mnNewMenu.add(mntmNewMenuItem_2);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
ArrayList columnNames = new ArrayList();
ArrayList data = new ArrayList();
// data_connector getdata1 = new data_connector();
// host = getdata1.getHost();
// username = getdata1.getUsername();
// password1 = getdata1.getPassword();
// mysql_command = getdata1.getMysql_command();
// command_name = getdata1.getCommand_name();
//setTitle(command_name);
// Connect to an MySQL Database, run query, get result set
String url = "jdbc:mysql://localhost:3306/υπαλληλοι απε-μπε";
String userid = "ziorange";
String password = "120736";
String sql = "SELECT * FROM `ΥΠΑΛΛΗΛΟΙ 2 test`";
//String sql = "SELECT `ΚΩΔΙΚΟΣ`,`ΕΠΩΝΥΜΟ`,`ΟΝΟΜΑ`,`ΟΝΟΜΑ ΠΑΤΡΟΣ`,`ΑΜΚΑ`,`ΑΡΙΘΜΟΣ ΜΗΤΡΩΟΥ ΙΚΑ (αν υπάρχει)` FROM `ΥΠΑΛΛΗΛΟΙ 2` WHERE `ΚΩΔΙΚΟΣ`>'0' AND `ΗΜΕΡΟΜΗΝΙΑ ΑΠΟΧΩΡΗΣΗΣ`>'2009-12-31 00:00:00' OR `ΕΙΔΙΚΟΤΗΤΑ` !='ΑΝΤΑΠΟΚΡΙΤΗΣ ΕΞ' AND `ΛΟΓΟΣ ΑΠΟΧΩΡΗΣΗΣ`='-' ORDER BY `ΕΠΩΝΥΜΟ`";
// Java SE 7 has try-with-resources
// This will ensure that the sql objects are closed when the program
// is finished with them
try
{
connection = DriverManager.getConnection( url, userid, password );
Statement stmt = connection.createStatement();
ResultSet rs = stmt.executeQuery( sql );
ResultSetMetaData md = rs.getMetaData();
int columns = md.getColumnCount();
// Get column names
for (int i = 1; i <= columns; i++)
{
columnNames.add( md.getColumnName(i) );
}
// Get row data
while (rs.next())
{
ArrayList row = new ArrayList(columns);
for (int i = 1; i <= columns; i++)
{
row.add( rs.getObject(i) );
}
data.add( row );
}
}
catch (SQLException e)
{
//
System.out.println( e.getMessage() );
JOptionPane.showMessageDialog(null, e.getMessage() );
mysql_fail_flag=1;
}
// Create Vectors and copy over elements from ArrayLists to them
// Vector is deprecated but I am using them in this example to keep
// things simple - the best practice would be to create a custom defined
// class which inherits from the AbstractTableModel class
Vector columnNamesVector = new Vector();
Vector dataVector = new Vector();
for (int i = 0; i < data.size(); i++)
{
ArrayList subArray = (ArrayList)data.get(i);
Vector subVector = new Vector();
for (int j = 0; j < subArray.size(); j++)
{
subVector.add(subArray.get(j));
}
dataVector.add(subVector);
}
for (int i = 0; i < columnNames.size(); i++ )
columnNamesVector.add(columnNames.get(i));
contentPane.setLayout(null);
// Create table with database data
table = new JTable(dataVector, columnNamesVector)
{
public Class getColumnClass(int column)
{
for (int row = 0; row < getRowCount(); row++)
{
Object o = getValueAt(row, column);
if (o != null)
{
return o.getClass();
}
}
return Object.class;
}
};
table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
table.setColumnSelectionAllowed(true); //epilegei to kathe keli ksexwrista
table.getSelectionModel().addListSelectionListener(
new RowColumnListSelectionListener());
table.getDefaultEditor(String.class).addCellEditorListener(
new CellEditorListener() {
public void editingCanceled(ChangeEvent e) {
System.out.println("editingCanceled");
}
public void editingStopped(ChangeEvent e) {
System.out.println("editingStopped: apply additional action");
rowIndexStart = table.getSelectedRow();
rowIndexEnd = table.getSelectionModel().getMaxSelectionIndex();
colIndexStart = table.getSelectedColumn();
colIndexEnd = table.getColumnModel().getSelectionModel().getMaxSelectionIndex();
for ( i = rowIndexStart; i <= rowIndexEnd; i++) {
for ( j = colIndexStart; j <= colIndexEnd; j++) {
Object cell_value = table.getValueAt(i,j);
Cell_value_string_after = (String) cell_value;
ia=i+1;
ja=j+1;
column_name_selected2 = table.getColumnName(ja-1);
}
}
if(Cell_value_string_before.equals(Cell_value_string_after)){
System.out.println("Do nothing");
}
else{
System.out.println("UPDATE DATABASE");
update_database();
}
}
});
JScrollPane scrollPane = new JScrollPane( table );
scrollPane.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS);
scrollPane.setBounds(5, 5, xframeWidth-20, yframeHeight-70);
getContentPane().add( scrollPane );
JPanel buttonPanel = new JPanel();
buttonPanel.setBounds(5, 856, 1574, 1);
getContentPane().add( buttonPanel );
buttonPanel.setLayout(null);
}
public void update_database(){
Object get_lastname = table.getValueAt(ia-1, 5);
String get_lastname_string = (String) get_lastname;
Object get_name = table.getValueAt(ia-1, 6);
String get_name_string=(String) get_name;
System.out.println("RESULT= "+ column_name_selected2 + " - "+Cell_value_string_after+ " - " + get_lastname_string+ " - " + get_name_string );
if(column_name_selected2.equals("ΕΠΩΝΥΜΟ") || column_name_selected2.equals("ΟΝΟΜΑ")){
JOptionPane.showMessageDialog(null, "To επώνυμο και το όνομα δεν μπορεί να αλλάξει","Μήνυμα:",JOptionPane.WARNING_MESSAGE);
}
else{
try {
PreparedStatement update = (PreparedStatement) connection.prepareStatement
("UPDATE `ΥΠΑΛΛΗΛΟΙ 2 TEST` SET `" +column_name_selected2+"` = ? WHERE ΕΠΩΝΥΜΟ= ? AND ΟΝΟΜΑ =? ");
update.setString(1,Cell_value_string_after);
update.setString(2,get_lastname_string);
update.setString(3,get_name_string);
int all_edit_query_status=update.executeUpdate();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}