在这里遇到了问题,试图在此刻创建一个到数据库系统的登录名。我必须上课:UserLogManagerMainWindow和DatabaseConnectionFrame。我的程序是关于日志管理的。我想建立数据库连接:
UserLogManagerMainWindow类具有一个“连接到数据库”按钮,单击DatabaseConnectionFrame初始化并获得一个带有jlabels和jtextfields的框架,在输入所需的所有内容后,我按“登录”按钮,此后,我希望我的UserLogManagerMainWindow类继续从连接的数据库中添加日志。
我已经写了一些有关其外观的代码:“关于我要说的逻辑”
connectToDatabaseBtn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
DatabaseConnectionFrame dcf = new DatabaseConnectionFrame();
dcf.setVisible(true);
if(dcf.answer == true) {
importButtons(menuBar);
setJMenuBar(menuBar);
try {
DatabaseComm.getColumnNamesToPanel(model, titles);
projects = DatabaseComm.AddLogsToArrayReturnProjectNames(events);
DatabaseComm.fillDataToPanel(model, events, titles, row);
DatabaseComm.resizeColumnWidth(table);
} catch (SQLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
else {
System.out.println("not working");
}
}
});
但是,如果声明不起作用,我知道为什么。这就是为什么我要问如何使其工作?更有可能的是,线程化是关键,但目前还不太好。有没有穿线的技巧吗?如果只有线程化方法,我可以从中获得帮助吗?
在下面提供DatabaseConnectionFrame类:
package manager;
import java.awt.BorderLayout;
import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import java.awt.GridBagLayout;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import java.awt.GridBagConstraints;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.InetAddress;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import javax.swing.JTextField;
import javax.swing.JPasswordField;
import javax.swing.SwingConstants;
import javax.swing.JButton;
public class DatabaseConnectionFrame extends JFrame{
private JPanel contentPane;
private JTextField address;
private JPasswordField password;
private JTextField username;
private JButton btnLogin;
private JButton btnCancel;
private JLabel lblPort;
private JTextField port;
public boolean answer = false;
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
DatabaseConnectionFrame frame = new DatabaseConnectionFrame();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public DatabaseConnectionFrame() {
setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
setSize(450,250);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
GridBagLayout gbl_contentPane = new GridBagLayout();
contentPane.setLayout(gbl_contentPane);
JLabel lblDatabaseIpAddress = new JLabel("Database ip address:");
GridBagConstraints gbc_lblDatabaseIpAddress = new GridBagConstraints();
gbc_lblDatabaseIpAddress.anchor = GridBagConstraints.EAST;
gbc_lblDatabaseIpAddress.insets = new Insets(0, 0, 5, 5);
gbc_lblDatabaseIpAddress.gridx = 0;
gbc_lblDatabaseIpAddress.gridy = 0;
contentPane.add(lblDatabaseIpAddress, gbc_lblDatabaseIpAddress);
address = new JTextField();
GridBagConstraints gbc_textField = new GridBagConstraints();
gbc_textField.insets = new Insets(0, 0, 5, 0);
gbc_textField.fill = GridBagConstraints.HORIZONTAL;
gbc_textField.gridx = 1;
gbc_textField.gridy = 0;
contentPane.add(address, gbc_textField);
address.setColumns(10);
lblPort = new JLabel("Port");
GridBagConstraints gbc_lblPort = new GridBagConstraints();
gbc_lblPort.anchor = GridBagConstraints.EAST;
gbc_lblPort.insets = new Insets(0, 0, 5, 5);
gbc_lblPort.gridx = 0;
gbc_lblPort.gridy = 1;
contentPane.add(lblPort, gbc_lblPort);
port = new JTextField();
GridBagConstraints gbc_textField1 = new GridBagConstraints();
gbc_textField1.insets = new Insets(0, 0, 5, 0);
gbc_textField1.fill = GridBagConstraints.HORIZONTAL;
gbc_textField1.gridx = 1;
gbc_textField1.gridy = 1;
contentPane.add(port, gbc_textField1);
port.setColumns(10);
JLabel lblUsername = new JLabel("Username:");
lblUsername.setHorizontalAlignment(SwingConstants.CENTER);
GridBagConstraints gbc_lblUsername = new GridBagConstraints();
gbc_lblUsername.anchor = GridBagConstraints.EAST;
gbc_lblUsername.insets = new Insets(0, 0, 5, 5);
gbc_lblUsername.gridx = 0;
gbc_lblUsername.gridy = 2;
contentPane.add(lblUsername, gbc_lblUsername);
username = new JTextField();
GridBagConstraints gbc_textField_1 = new GridBagConstraints();
gbc_textField_1.insets = new Insets(0, 0, 5, 0);
gbc_textField_1.fill = GridBagConstraints.HORIZONTAL;
gbc_textField_1.gridx = 1;
gbc_textField_1.gridy = 2;
contentPane.add(username, gbc_textField_1);
username.setColumns(10);
JLabel lblPassword = new JLabel("Password");
GridBagConstraints gbc_lblPassword = new GridBagConstraints();
gbc_lblPassword.anchor = GridBagConstraints.EAST;
gbc_lblPassword.insets = new Insets(0, 0, 5, 5);
gbc_lblPassword.gridx = 0;
gbc_lblPassword.gridy = 3;
contentPane.add(lblPassword, gbc_lblPassword);
password = new JPasswordField();
GridBagConstraints gbc_passwordField = new GridBagConstraints();
gbc_passwordField.insets = new Insets(0, 0, 5, 0);
gbc_passwordField.fill = GridBagConstraints.HORIZONTAL;
gbc_passwordField.gridx = 1;
gbc_passwordField.gridy = 3;
contentPane.add(password, gbc_passwordField);
btnLogin = new JButton("Login");
GridBagConstraints gbc_btnLogin = new GridBagConstraints();
gbc_btnLogin.insets = new Insets(0, 0, 0, 5);
gbc_btnLogin.gridx = 0;
gbc_btnLogin.gridy = 4;
contentPane.add(btnLogin, gbc_btnLogin);
btnCancel = new JButton("Cancel");
GridBagConstraints gbc_btnCancel = new GridBagConstraints();
gbc_btnCancel.gridx = 1;
gbc_btnCancel.gridy = 4;
contentPane.add(btnCancel, gbc_btnCancel);
btnCancel.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
dispose();
}
});
btnLogin.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
String dbAddress = address.getText();
String dbPort = port.getText();
String dbUsername = username.getText();
char[] dbPassword = password.getPassword();
if( dbAddress.isEmpty() || dbPort.isEmpty() || dbUsername.isEmpty() || dbPassword.length == 0) {
JOptionPane.showMessageDialog(getParent(),
"All fields have to be filled!");
}
else {
if(databaseValidation(dbAddress, dbPort, dbUsername, dbPassword)) {
JOptionPane.showMessageDialog(getParent(),
"Connected!");
answer = true;
setVisible(false);
}
else {
JOptionPane.showMessageDialog(getParent(),
"There was error connecting to the database!");
answer = false;
}
}
System.out.println(answer);
}
});
}
public boolean databaseValidation(String address, String port, String username, char[] password) {
String pw = String.valueOf(password);
System.out.println(pw);
try {
Connection con = DriverManager.getConnection("jdbc:mysql://" + address + ":" + port + "/logctrl?user=" + username + "&password=" + pw );
} catch (SQLException e) {
System.out.println("Error connecting to database!");
return false;
}
System.out.println("Connected");
return true;
}
}
最佳答案
如果要等待用户输入,则有两种选择,您可以选择自己的观察者模式,以将来以某种方式更改状态时调用该模式,也可以使用对话框来阻止代码在对话框可见的那一刻执行,将等到对话框关闭
有关详细信息,请参见How to use dialogs
import java.awt.Frame;
import java.awt.GridBagLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
public TestPane() {
setLayout(new GridBagLayout());
JButton btn = new JButton("Show the dialog");
add(btn);
btn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
JDialog dialog = new JDialog((Frame)SwingUtilities.getWindowAncestor(TestPane.this), "I'm in charge now", true);
JButton btn = new JButton("Waiting");
btn.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
dialog.dispose();
}
});
dialog.add(btn);
dialog.pack();
dialog.setLocationRelativeTo(TestPane.this);
dialog.setVisible(true);
JOptionPane.showMessageDialog(TestPane.this, "You won't see this till the dialog is closed");
}
});
}
}
}