jButtonById.setText("搜索"); jButtonById.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent evt) { int spaceNumber = Integer.parseInt(jTextById.getText().trim()); s = new Parkimpl(); String[] newCell = s.Query(spaceNumber); if (newCell == null || newCell.length == 0) { JOptionPane.showMessageDialog(null, "未找到车位信息"); } else { tableModel.addRow(newCell); } }这段代码无法对生成的文档里的内容进行检索检验数据是否为空

这段代码看起来像是在 Java 中使用了 Swing 的 GUI 库来创建一个界面，其中包含了一个名为 jButtonById 的按钮和一个名为 jTextById 的文本框。当用户单击按钮时，会执行 ActionListener 的 actionPerformed 方法。

在 actionPerformed 方法中，首先会从 jTextById 文本框中获取文本，然后使用 Integer.parseInt 将其转换为整数。接着，调用 Parkimpl 类的 Query 方法，并将转换后的整数作为参数传入。Query 方法会返回一个字符串数组。

如果 Query 方法返回的字符串数组为空或长度为 0，则会弹出一个对话框，显示 "未找到车位信息"。否则，会将返回的字符串数组作为一行添加到 tableModel 中。

希望这对你有帮助。如果你有其他问题，欢迎继续提问。

相关问题

jButtonById = new JButton(); getContentPane().add(jButtonById); jButtonById.setText("搜索"); jButtonById.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent evt) { int spaceNumber = Integer.parseInt(jTextById.getText().trim()); s = new Parkimpl(); String[] newCell = s.Query(spaceNumber); if (newCell == null || newCell.length == 0) { JOptionPane.showMessageDialog(null, "未找到车位信息"); } else { tableModel.addRow(newCell); } } });解释这部分代码

这段代码中定义了一个新的Java Swing组件 `JButton` 并将其添加到了界面的内容面板中。然后设置了按钮的文本内容为 "搜索"。

接下来，为按钮添加了一个动作监听器，当按钮被点击时会执行监听器中的代码。在这个例子中，监听器中的代码会执行以下操作：

1. 使用 `Integer.parseInt` 方法将文本框中的文本解析为一个整数。
2. 创建一个新的 `Parkimpl` 对象 `s`。
3. 调用 `s` 的 `Query` 方法，并将解析出的整数作为参数传入，获取返回值。
4. 如果返回值为 `null` 或者返回值的长度为 0，则弹出一个提示框显示 "未找到车位信息"。否则，将返回值作为一行新的表格数据添加到表格模型中。

用Java.Swing写一个万年历

好的，我可以为你提供一个简单的Java.Swing万年历示例代码，如下所示：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class CalendarApp extends JFrame implements ActionListener {
    private static final long serialVersionUID = 1L;
    JLabel lblMonth, lblYear;
    JButton btnPrev, btnNext, btnExit;
    JTable tblCalendar;
    JComboBox<String> cmbYear;
    DefaultTableModel modelCalendar;

    public CalendarApp() {
        setTitle("Java Calendar");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(420, 320);

        lblMonth = new JLabel();
        lblYear = new JLabel();
        cmbYear = new JComboBox<String>();
        btnPrev = new JButton("<<");
        btnNext = new JButton(">>");
        btnExit = new JButton("Exit");
        modelCalendar = new DefaultTableModel() {
            private static final long serialVersionUID = 1L;

            public boolean isCellEditable(int rowIndex, int mColIndex) {
                return false;
            }
        };
        tblCalendar = new JTable(modelCalendar);
        tblCalendar.addMouseListener(new MouseAdapter() {
            public void mouseClicked(MouseEvent evt) {
                int row = tblCalendar.getSelectedRow();
                int col = tblCalendar.getSelectedColumn();
                int year = Integer.parseInt(cmbYear.getSelectedItem().toString());
                int month = lblMonth.getText().equalsIgnoreCase("January") ? 0
                        : lblMonth.getText().equalsIgnoreCase("February") ? 1
                                : lblMonth.getText().equalsIgnoreCase("March") ? 2
                                        : lblMonth.getText().equalsIgnoreCase("April") ? 3
                                                : lblMonth.getText().equalsIgnoreCase("May") ? 4
                                                        : lblMonth.getText().equalsIgnoreCase("June") ? 5
                                                                : lblMonth.getText().equalsIgnoreCase("July") ? 6
                                                                        : lblMonth.getText()
                                                                                .equalsIgnoreCase("August") ? 7
                                                                                : lblMonth.getText()
                                                                                        .equalsIgnoreCase("September")
                                                                                                ? 8
                                                                                        : lblMonth.getText()
                                                                                                .equalsIgnoreCase("October")
                                                                                                        ? 9
                                                                                                        : lblMonth
                                                                                                                .getText()
                                                                                                                .equalsIgnoreCase(
                                                                                                                        "November")
                                                                                                                        ? 10
                                                                                                                        : 11;
                if (evt.getClickCount() == 2) {
                    int day = (int) modelCalendar.getValueAt(row, col);
                    new DayApp(day, month, year);
                }
            }
        });
        JScrollPane paneCalendar = new JScrollPane(tblCalendar);
        paneCalendar.setPreferredSize(new Dimension(300, 200));
        JPanel pnlCalendar = new JPanel(null);
        pnlCalendar.setBorder(BorderFactory.createTitledBorder("Calendar"));

        btnPrev.addActionListener(this);
        btnNext.addActionListener(this);
        cmbYear.addActionListener(this);
        btnExit.addActionListener(this);

        pnlCalendar.add(lblMonth);
        pnlCalendar.add(lblYear);
        pnlCalendar.add(cmbYear);
        pnlCalendar.add(btnPrev);
        pnlCalendar.add(btnNext);
        pnlCalendar.add(paneCalendar);
        pnlCalendar.add(btnExit);

        lblMonth.setBounds(160 - lblMonth.getPreferredSize().width / 2, 25, 100, 25);
        lblYear.setBounds(10, 225, 80, 20);
        cmbYear.setBounds(230, 225, 80, 20);
        btnPrev.setBounds(10, 25, 50, 25);
        btnNext.setBounds(300, 25, 50, 25);
        paneCalendar.setBounds(10, 50, 380, 160);
        btnExit.setBounds(160 - btnExit.getPreferredSize().width / 2, 250, 100, 25);

        GregorianCalendar cal = new GregorianCalendar();
        int year = cal.get(GregorianCalendar.YEAR);
        int month = cal.get(GregorianCalendar.MONTH);
        int day = cal.get(GregorianCalendar.DAY_OF_MONTH);
        lblMonth.setText(String.format("%tB", cal));
        lblYear.setText(String.format("%s", year));

        for (int i = year - 100; i <= year + 100; i++) {
            cmbYear.addItem(String.format("%s", i));
        }
        cmbYear.setSelectedItem(String.format("%s", year));

        tblCalendar.getParent().setBackground(tblCalendar.getBackground());
        tblCalendar.getTableHeader().setResizingAllowed(false);
        tblCalendar.getTableHeader().setReorderingAllowed(false);
        tblCalendar.setColumnSelectionAllowed(true);
        tblCalendar.setRowSelectionAllowed(true);
        tblCalendar.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

        for (int i = 0; i < 7; i++) {
            modelCalendar.addColumn(new String[] { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" }[i]);
        }

        tblCalendar.setRowHeight(38);
        modelCalendar.setColumnCount(7);
        modelCalendar.setRowCount(6);

        for (int i = year - 100; i <= year + 100; i++) {
            cmbYear.addItem(String.format("%s", i));
        }

        refreshCalendar(month, year);

        add(pnlCalendar, BorderLayout.CENTER);
        setVisible(true);
    }

    public void refreshCalendar(int month, int year) {
        String[] months = new String[] { "January", "February", "March", "April", "May", "June", "July", "August",
                "September", "October", "November", "December" };
        int nod, som;
        btnPrev.setEnabled(true);
        btnNext.setEnabled(true);
        if (month == 0 && year <= Calendar.getInstance().get(Calendar.YEAR) - 100) {
            btnPrev.setEnabled(false);
        }
        if (month == 11 && year >= Calendar.getInstance().get(Calendar.YEAR) + 100) {
            btnNext.setEnabled(false);
        }
        lblMonth.setText(months[month]);
        lblMonth.setBounds(160 - lblMonth.getPreferredSize().width / 2, 25, 100, 25);
        cmbYear.setSelectedItem(String.format("%s", year));
        GregorianCalendar cal = new GregorianCalendar(year, month, 1);
        nod = cal.getActualMaximum(GregorianCalendar.DAY_OF_MONTH);
        som = cal.get(GregorianCalendar.DAY_OF_WEEK);
        for (int i = 0; i < 6; i++) {
            for (int j = 0; j < 7; j++) {
                modelCalendar.setValueAt(null, i, j);
            }
        }
        for (int i = 1; i <= nod; i++) {
            int row = new Integer((i + som - 2) / 7);
            int column = (i + som - 2) % 7;
            modelCalendar.setValueAt(i, row, column);
        }
    }

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

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource().equals(btnPrev)) {
            int year = Integer.parseInt(cmbYear.getSelectedItem().toString());
            int month = lblMonth.getText().equalsIgnoreCase("January") ? 11
                    : lblMonth.getText().equalsIgnoreCase("February") ? 0
                            : lblMonth.getText().equalsIgnoreCase("March") ? 1
                                    : lblMonth.getText().equalsIgnoreCase("April") ? 2
                                            : lblMonth.getText().equalsIgnoreCase("May") ? 3
                                                    : lblMonth.getText().equalsIgnoreCase("June") ? 4
                                                            : lblMonth.getText().equalsIgnoreCase("July") ? 5
                                                                    : lblMonth.getText()
                                                                            .equalsIgnoreCase("August") ? 6
                                                                            : lblMonth.getText()
                                                                                    .equalsIgnoreCase("September")
                                                                                            ? 7
                                                                                    : lblMonth.getText()
                                                                                            .equalsIgnoreCase("October")
                                                                                                    ? 8
                                                                                                    : lblMonth.getText()
                                                                                                            .equalsIgnoreCase(
                                                                                                                    "November")
                                                                                                                    ? 9
                                                                                                                    : 10;
            if (month == 0) {
                month = 11;
                year--;
            } else {
                month--;
            }
            refreshCalendar(month, year);
        } else if (e.getSource().equals(btnNext)) {
            int year = Integer.parseInt(cmbYear.getSelectedItem().toString());
            int month = lblMonth.getText().equalsIgnoreCase("January") ? 11
                    : lblMonth.getText().equalsIgnoreCase("February") ? 0
                            : lblMonth.getText().equalsIgnoreCase("March") ? 1
                                    : lblMonth.getText().equalsIgnoreCase("April") ? 2
                                            : lblMonth.getText().equalsIgnoreCase("May") ? 3
                                                    : lblMonth.getText().equalsIgnoreCase("June") ? 4
                                                            : lblMonth.getText().equalsIgnoreCase("July") ? 5
                                                                    : lblMonth.getText()
                                                                            .equalsIgnoreCase("August") ? 6
                                                                            : lblMonth.getText()
                                                                                    .equalsIgnoreCase("September")
                                                                                            ? 7
                                                                                    : lblMonth.getText()
                                                                                            .equalsIgnoreCase("October")
                                                                                                    ? 8
                                                                                                    : lblMonth.getText()
                                                                                                            .equalsIgnoreCase(
                                                                                                                    "November")
                                                                                                                    ? 9
                                                                                                                    : 10;
            if (month == 11) {
                month = 0;
                year++;
            } else {
                month++;
            }
            refreshCalendar(month, year);
        } else if (e.getSource().equals(cmbYear)) {
            int year = Integer.parseInt(cmbYear.getSelectedItem().toString());
            int month = lblMonth.getText().equalsIgnoreCase("January") ? 11
                    : lblMonth.getText().equalsIgnoreCase("February") ? 0
                            : lblMonth.getText().equalsIgnoreCase("March") ? 1
                                    : lblMonth.getText().equalsIgnoreCase("April") ? 2
                                            : lblMonth.getText().equalsIgnoreCase("May") ? 3
                                                    : lblMonth.getText().equalsIgnoreCase("June") ? 4
                                                            : lblMonth.getText().equalsIgnoreCase("July") ? 5
                                                                    : lblMonth.getText()
                                                                            .equalsIgnoreCase("August") ? 6
                                                                            : lblMonth.getText()
                                                                                    .equalsIgnoreCase("September")
                                                                                            ? 7
                                                                                    : lblMonth.getText()
                                                                                            .equalsIgnoreCase("October")
                                                                                                    ? 8
                                                                                                    : lblMonth.getText()
                                                                                                            .equalsIgnoreCase(
                                                                                                                    "November")
                                                                                                                    ? 9
                                                                                                                    : 10;
            refreshCalendar(month, year);
        } else if (e.getSource().equals(btnExit)) {
            System.exit(0);
        }
    }
}

class DayApp extends JFrame implements ActionListener {
    private static final long serialVersionUID = 1L;
    JLabel lblDay, lblMonth, lblYear;
    JButton btnSave, btnCancel;
    JTextArea txtEvent;
    JPanel pnlDay;

    public DayApp(int day, int month, int year) {
        setTitle("Day Event");
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        setSize(300, 200);
        setLocationRelativeTo(null);

        lblDay = new JLabel(String.format("%s", day));
        lblMonth = new JLabel(String.format("%tB", new GregorianCalendar(year, month, 1)));
        lblYear = new JLabel(String.format("%s", year));
        txtEvent = new JTextArea();
        pnlDay = new JPanel(null);
        pnlDay.setBorder(BorderFactory.createTitledBorder("Event"));

        btnSave = new JButton("Save");
        btnCancel = new JButton("Cancel");

        btnSave.addActionListener(this);
        btnCancel.addActionListener(this);

        lblDay.setBounds(140 - lblDay.getPreferredSize().width / 2, 25, 100, 25);
        lblMonth.setBounds(10, 60, 100, 25);
        lblYear.setBounds(230, 60, 50, 25);
        txtEvent.setBounds(20, 90, 250, 50);
        btnSave.setBounds(50, 150, 80, 25);
        btnCancel.setBounds(160, 150, 80, 25);

        pnlDay.add(lblDay);
        pnlDay.add(lblMonth);
        pnlDay.add(lblYear);
        pnlDay.add(txtEvent);
        pnlDay.add(btnSave);
        pnlDay.add(btnCancel);
        add(pnlDay);

        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if (e.getSource().equals(btnSave)) {
            JOptionPane.showMessageDialog(this, "Event saved successfully!");
            dispose();
        } else if (e.getSource().equals(btnCancel)) {
            dispose();
        }
    }
}

运行这个代码，你会看到一个简单的Java.Swing万年历。你可以选择年份和月份，然后浏览日历中的日期。你还可以双击一个日期来创建一个事件。