<project xmlns="http://maven.apache.org/POM/4.0.0" ...>
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.example.rtfviewer</groupId>
  <artifactId>rtf-viewer</artifactId>
  <version>1.0.0</version>
  <properties>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>
  <dependencies>
    <!-- JUnit 5 -->
    <dependency>
      <groupId>org.junit.jupiter</groupId>
      <artifactId>junit-jupiter</artifactId>
      <version>5.9.2</version>
      <scope>test</scope>
    </dependency>
    <!-- SLF4J + Logback -->
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>1.4.8</version>
    </dependency>
  </dependencies>
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <version>3.0.0-M7</version>
      </plugin>
    </plugins>
  </build>
</project>

// 文件：src/main/java/com/example/rtfviewer/RtfViewer.java
package com.example.rtfviewer;
 
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.File;
 
/**
 * 主界面：RTF 文件查看器
 */
public class RtfViewer extends JFrame {
    private final RtfPanel rtfPanel;
    private final FindDialog findDialog;
 
    public RtfViewer() {
        super("RTF 文件查看器");
        setDefaultCloseOperation(EXIT_ON_CLOSE);
        setSize(800, 600);
        setLocationRelativeTo(null);
 
        rtfPanel = new RtfPanel();
        findDialog = new FindDialog(this, rtfPanel);
 
        setJMenuBar(createMenuBar());
        add(createToolBar(), BorderLayout.NORTH);
        add(new JScrollPane(rtfPanel), BorderLayout.CENTER);
    }
 
    private JMenuBar createMenuBar() {
        JMenuBar mb = new JMenuBar();
        JMenu file = new JMenu("文件");
        JMenuItem open = new JMenuItem("打開");
        open.addActionListener(e -> openFile());
        file.add(open);
        mb.add(file);
 
        JMenu view = new JMenu("查看");
        JMenuItem zoomIn = new JMenuItem("放大");
        zoomIn.addActionListener(e -> rtfPanel.zoomIn());
        JMenuItem zoomOut = new JMenuItem("縮小");
        zoomOut.addActionListener(e -> rtfPanel.zoomOut());
        view.add(zoomIn); view.add(zoomOut);
        JMenuItem find = new JMenuItem("查找");
        find.addActionListener(e -> findDialog.setVisible(true));
        view.add(find);
        mb.add(view);
        return mb;
    }
 
    private JToolBar createToolBar() {
        JToolBar tb = new JToolBar();
        JButton btnOpen = new JButton("打開");
        btnOpen.addActionListener(e -> openFile());
        JButton btnZoomIn = new JButton("放大");
        btnZoomIn.addActionListener(e -> rtfPanel.zoomIn());
        JButton btnZoomOut = new JButton("縮小");
        btnZoomOut.addActionListener(e -> rtfPanel.zoomOut());
        JButton btnFind = new JButton("查找");
        btnFind.addActionListener(e -> findDialog.setVisible(true));
        tb.add(btnOpen); tb.add(btnZoomIn); tb.add(btnZoomOut); tb.add(btnFind);
        return tb;
    }
 
    private void openFile() {
        JFileChooser chooser = new JFileChooser();
        chooser.setFileFilter(new javax.swing.filechooser.FileNameExtensionFilter("RTF 文檔", "rtf"));
        int ret = chooser.showOpenDialog(this);
        if (ret == JFileChooser.APPROVE_OPTION) {
            File file = chooser.getSelectedFile();
            rtfPanel.loadRtf(file);
        }
    }
}
 
// 文件：src/main/java/com/example/rtfviewer/RtfPanel.java
package com.example.rtfviewer;
 
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.text.rtf.RTFEditorKit;
import java.awt.*;
import java.io.*;
import java.util.*;
import org.slf4j.*;
 
/**
 * RTF 文檔顯示面板
 */
public class RtfPanel extends JTextPane {
    private static final Logger logger = LoggerFactory.getLogger(RtfPanel.class);
    private float fontSize = 12f;
 
    public RtfPanel() {
        super();
        setEditable(false);
        setEditorKit(new RTFEditorKit());
        setFont(getFont().deriveFont(fontSize));
    }
 
    /**
     * 加載并顯示 RTF 文件
     */
    public void loadRtf(File file) {
        try (InputStream in = new FileInputStream(file)) {
            Document doc = getEditorKit().createDefaultDocument();
            getEditorKit().read(in, doc, 0);
            setDocument(doc);
            setCaretPosition(0);
            logger.info("成功加載 RTF 文件：{}", file.getAbsolutePath());
        } catch (Exception ex) {
            logger.error("加載 RTF 文件失敗", ex);
            JOptionPane.showMessageDialog(this, "加載失?。? + ex.getMessage(), "錯誤", JOptionPane.ERROR_MESSAGE);
        }
    }
 
    /** 放大字體 */
    public void zoomIn() {
        fontSize = Math.min(fontSize + 2f, 48f);
        setFont(getFont().deriveFont(fontSize));
    }
 
    /** 縮小字體 */
    public void zoomOut() {
        fontSize = Math.max(fontSize - 2f, 8f);
        setFont(getFont().deriveFont(fontSize));
    }
 
    /**
     * 查找并高亮關鍵詞
     * @param keyword 關鍵詞
     * @return 所有匹配位置列表
     */
    public List<MatchPosition> find(String keyword) {
        List<MatchPosition> result = new ArrayList<>();
        removeHighlights();
        if (keyword == null || keyword.isEmpty()) return result;
        try {
            StyledDocument doc = getStyledDocument();
            String text = doc.getText(0, doc.getLength()).toLowerCase();
            String key = keyword.toLowerCase();
            int index = 0;
            Highlighter hilite = getHighlighter();
            Highlighter.HighlightPainter painter = new DefaultHighlighter.DefaultHighlightPainter(Color.YELLOW);
            while ((index = text.indexOf(key, index)) >= 0) {
                hilite.addHighlight(index, index + key.length(), painter);
                result.add(new MatchPosition(index, key.length()));
                index += key.length();
            }
        } catch (BadLocationException e) {
            logger.warn("查找出錯", e);
        }
        return result;
    }
 
    /** 清除所有高亮 */
    public void removeHighlights() {
        getHighlighter().removeAllHighlights();
    }
}
 
// 文件：src/main/java/com/example/rtfviewer/FindDialog.java
package com.example.rtfviewer;
 
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.List;
 
/**
 * 查找對話框
 */
public class FindDialog extends JDialog {
    private final JTextField tfKeyword = new JTextField(20);
    private final JButton btnNext = new JButton("下一個");
    private final JButton btnPrev = new JButton("上一個");
    private List<MatchPosition> matches = Collections.emptyList();
    private int currentIndex = -1;
    private final RtfPanel rtfPanel;
 
    public FindDialog(JFrame owner, RtfPanel panel) {
        super(owner, "查找", false);
        this.rtfPanel = panel;
        setLayout(new FlowLayout(FlowLayout.LEFT, 5, 10));
        add(new JLabel("關鍵詞："));
        add(tfKeyword);
        add(btnNext);
        add(btnPrev);
        setSize(350, 120);
        setLocationRelativeTo(owner);
 
        tfKeyword.addActionListener(e -> doSearch());
        btnNext.addActionListener(e -> moveTo(true));
        btnPrev.addActionListener(e -> moveTo(false));
    }
 
    private void doSearch() {
        matches = rtfPanel.find(tfKeyword.getText());
        currentIndex = -1;
        if (!matches.isEmpty()) {
            moveTo(true);
        }
    }
 
    private void moveTo(boolean forward) {
        if (matches.isEmpty()) return;
        currentIndex = forward ? (currentIndex + 1) % matches.size()
                               : (currentIndex - 1 + matches.size()) % matches.size();
        MatchPosition pos = matches.get(currentIndex);
        rtfPanel.setCaretPosition(pos.getOffset());
        rtfPanel.requestFocusInWindow();
    }
}
 
// 文件：src/main/java/com/example/rtfviewer/MatchPosition.java
package com.example.rtfviewer;
 
/**
 * 匹配位置記錄
 */
public class MatchPosition {
    private final int offset;
    private final int length;
    public MatchPosition(int offset, int length) {
        this.offset = offset;
        this.length = length;
    }
    public int getOffset() { return offset; }
    public int getLength() { return length; }
}
 
// 文件：src/main/java/com/example/rtfviewer/DemoMain.java
package com.example.rtfviewer;
 
import javax.swing.*;
 
/**
 * 啟動類
 */
public class DemoMain {
    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new RtfViewer().setVisible(true));
    }
}
 
// 文件：src/test/java/com/example/rtfviewer/RtfViewerTest.java
package com.example.rtfviewer;
 
import org.junit.jupiter.api.*;
import javax.swing.text.*;
import java.io.*;
import static org.junit.jupiter.api.Assertions.*;
 
/**
 * 單元測試 RtfPanel 加載與查找
 */
class RtfViewerTest {
    private RtfPanel panel;
 
    @BeforeEach
    void setUp() {
        panel = new RtfPanel();
    }
 
    @Test
    void testLoadEmpty() {
        File tmp = new File("src/test/resources/empty.rtf");
        panel.loadRtf(tmp);
        try {
            String text = panel.getDocument().getText(0, panel.getDocument().getLength());
            assertTrue(text.trim().isEmpty());
        } catch (Exception e) {
            fail(e);
        }
    }
 
    @Test
    void testFind() {
        // 向文檔插入測試字符串
        try {
            StyledDocument doc = (StyledDocument) panel.getDocument();
            doc.insertString(0, "Hello RTF Viewer Hello", null);
        } catch (BadLocationException e) {
            fail(e);
        }
        List<MatchPosition> matches = panel.find("Hello");
        assertEquals(2, matches.size());
        assertEquals(0, matches.get(0).getOffset());
        assertEquals(18, matches.get(1).getOffset());
    }
}