完善QQ登录窗口，实现以下功能：模拟你的QQ帐号登录，对帐号格式进行验证，即帐号只能是数字型数据，密码框支持敲回车键相当于单击登录按钮的效果。如果登录成功，则出现一确认对话框（showConfirmDialog），上面显示“XXX，您好！欢迎您！”，如果登录不成功，则出现一消息对话框（showMessageDialog），显示“对不起，你输入的帐号或密码有误，请重新输入！”，字体大小为13号，单击“关闭”按钮，可关闭此对话框；图片可以随时间变化，如系统时间为单号显示左下图的界面，双号则显示为右下图的界面。

这是一个具体的编程问题，需要使用Java Swing编写窗口和对话框，以及使用Java代码进行帐号验证和时间获取。以下是代码示例：

import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Calendar;
import java.util.regex.Pattern;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;

public class QQLoginWindow extends JFrame implements ActionListener {
    private static final long serialVersionUID = 1L;
    private JTextField accountField;
    private JPasswordField passwordField;

    public QQLoginWindow() {
        super("QQ登录");
        JPanel accountPanel = new JPanel(new FlowLayout());
        JLabel accountLabel = new JLabel("QQ帐号：");
        accountField = new JTextField(10);
        accountPanel.add(accountLabel);
        accountPanel.add(accountField);

        JPanel passwordPanel = new JPanel(new FlowLayout());
        JLabel passwordLabel = new JLabel("密码：");
        passwordField = new JPasswordField(10);
        passwordField.addActionListener(this);
        passwordPanel.add(passwordLabel);
        passwordPanel.add(passwordField);

        JPanel buttonPanel = new JPanel(new FlowLayout());
        JButton loginButton = new JButton("登录");
        loginButton.addActionListener(this);
        buttonPanel.add(loginButton);

        add(accountPanel);
        add(passwordPanel);
        add(buttonPanel);

        setSize(250, 150);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        setVisible(true);
    }

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

    @Override
    public void actionPerformed(ActionEvent e) {
        if (validateAccountFormat(accountField.getText()) && validatePassword()) {
            showConfirmationDialog();
        } else {
            showMessageDialog();
        }
    }

    private boolean validateAccountFormat(String account) {
        return Pattern.matches("\\d+", account);
    }

    private boolean validatePassword() {
        return new String(passwordField.getPassword()).equals("123456");
    }

    private void showConfirmationDialog() {
        String username = accountField.getText();
        String message = username + "，您好！欢迎您！";
        JOptionPane.showConfirmDialog(this, message, "登录成功", JOptionPane.DEFAULT_OPTION);
    }

    private void showMessageDialog() {
        String message = "对不起，你输入的帐号或密码有误，请重新输入！";
        JLabel label = new JLabel(message);
        label.setFont(new Font("宋体", Font.PLAIN, 13));
        JOptionPane.showMessageDialog(this, label, "登录失败", JOptionPane.ERROR_MESSAGE);
    }

    private static boolean isOdd(Calendar calendar) {
        return calendar.get(Calendar.DAY_OF_MONTH) % 2 != 0;
    }

    private static void showWindow() {
        JFrame frame = new JFrame();
        frame.setTitle("QQ登录");
        frame.setSize(400, 300);
        frame.setLocationRelativeTo(null);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        Calendar calendar = Calendar.getInstance();
        int hour = calendar.get(Calendar.HOUR_OF_DAY);
        String imageName = isOdd(calendar) ? "left.png" : "right.png";
        JLabel imageLabel = new JLabel();
        imageLabel.setIcon(new ImageIcon(imageName));
        frame.add(imageLabel);

        frame.setVisible(true);
    }
}

注意，这只是一个简单的示例，实际应用中需要进行更严格的帐号验证和密码加密等操作。