用Java代码编写一个程序实现一下功能 1）从已有的图象文件列表中选择某一个，即可显示该图象，并可做旋转等变换。 2）在画布区域上可以进行各种规则图形的绘制（如：线段、矩形、多边形、圆等），还可通过鼠标的拖动自由绘图。 3）可以连续播放所选文件夹下的所有图象。

好的，以下是Java代码实现上述功能的示例：

1. 显示图像并进行变换：

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;

public class ImageDisplay extends JFrame implements ActionListener {

    private JLabel imageLabel;
    private BufferedImage image;
    private JComboBox<String> imageList;
    private JCheckBox rotateBox;
    private JButton rotateButton;
    private double angle = 0.0;

    public ImageDisplay() {
        super("Image Display");

        JPanel controlPanel = new JPanel();
        controlPanel.setLayout(new FlowLayout());

        JLabel label = new JLabel("Select Image:");
        controlPanel.add(label);

        // 添加下拉列表框用于选择图像文件
        imageList = new JComboBox<String>(new String[]{"image1.jpg", "image2.jpg", "image3.jpg"});
        imageList.addActionListener(this);
        controlPanel.add(imageList);

        // 添加复选框用于控制是否旋转
        rotateBox = new JCheckBox("Rotate");
        rotateBox.addActionListener(this);
        controlPanel.add(rotateBox);

        // 添加按钮用于执行旋转操作
        rotateButton = new JButton("Rotate");
        rotateButton.addActionListener(this);
        controlPanel.add(rotateButton);

        // 将控制面板添加到窗口的南侧
        add(controlPanel, BorderLayout.SOUTH);

        // 读取默认的图像文件并将其显示
        try {
            image = ImageIO.read(new File(imageList.getSelectedItem().toString()));
            imageLabel = new JLabel(new ImageIcon(image));
            add(imageLabel, BorderLayout.CENTER);
        } catch (IOException e) {
            e.printStackTrace();
        }

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(800, 600);
        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        Object source = e.getSource();

        if (source == imageList) {
            // 当下拉列表框的选项改变时，读取新的图像文件并显示
            try {
                image = ImageIO.read(new File(imageList.getSelectedItem().toString()));
                imageLabel.setIcon(new ImageIcon(image));
                angle = 0.0;
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        } else if (source == rotateBox || source == rotateButton) {
            // 当复选框或按钮被选中时，旋转图像
            if (rotateBox.isSelected()) {
                angle += Math.PI / 4.0;
            } else {
                angle -= Math.PI / 4.0;
            }
            // 使用 AffineTransform 对图像进行变换
            AffineTransform transform = new AffineTransform();
            transform.translate(image.getWidth() / 2.0, image.getHeight() / 2.0);
            transform.rotate(angle);
            transform.translate(-image.getWidth() / 2.0, -image.getHeight() / 2.0);
            BufferedImage rotatedImage = new BufferedImage(image.getWidth(), image.getHeight(), image.getType());
            Graphics2D g = rotatedImage.createGraphics();
            g.drawImage(image, transform, null);
            g.dispose();
            imageLabel.setIcon(new ImageIcon(rotatedImage));
        }
    }

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

2. 绘制图形：

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

public class DrawingApplication extends JFrame implements MouseListener, MouseMotionListener, ActionListener {

    private JPanel canvas;
    private JButton lineButton, rectButton, ellipseButton, polygonButton, freehandButton;
    private Shape currentShape;
    private Point startPoint, endPoint;
    private Polygon currentPolygon;

    public DrawingApplication() {
        super("Drawing Application");

        // 创建绘图区域
        canvas = new JPanel() {
            @Override
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                if (currentShape != null) {
                    ((Graphics2D) g).draw(currentShape);
                }
                if (currentPolygon != null) {
                    ((Graphics2D) g).drawPolygon(currentPolygon);
                }
            }
        };
        canvas.setBackground(Color.WHITE);
        canvas.addMouseListener(this);
        canvas.addMouseMotionListener(this);
        add(canvas, BorderLayout.CENTER);

        // 创建绘图工具栏
        JPanel toolBar = new JPanel();
        toolBar.setLayout(new FlowLayout());

        lineButton = new JButton("Line");
        lineButton.addActionListener(this);
        toolBar.add(lineButton);

        rectButton = new JButton("Rectangle");
        rectButton.addActionListener(this);
        toolBar.add(rectButton);

        ellipseButton = new JButton("Ellipse");
        ellipseButton.addActionListener(this);
        toolBar.add(ellipseButton);

        polygonButton = new JButton("Polygon");
        polygonButton.addActionListener(this);
        toolBar.add(polygonButton);

        freehandButton = new JButton("Freehand");
        freehandButton.addActionListener(this);
        toolBar.add(freehandButton);

        add(toolBar, BorderLayout.NORTH);

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(800, 600);
        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        Object source = e.getSource();
        if (source == lineButton) {
            currentShape = null;
            currentPolygon = null;
            canvas.repaint();
            JOptionPane.showMessageDialog(this, "Click and drag to draw a line");
        } else if (source == rectButton) {
            currentShape = null;
            currentPolygon = null;
            canvas.repaint();
            JOptionPane.showMessageDialog(this, "Click and drag to draw a rectangle");
        } else if (source == ellipseButton) {
            currentShape = null;
            currentPolygon = null;
            canvas.repaint();
            JOptionPane.showMessageDialog(this, "Click and drag to draw an ellipse");
        } else if (source == polygonButton) {
            currentShape = null;
            currentPolygon = new Polygon();
            canvas.repaint();
            JOptionPane.showMessageDialog(this, "Click to add points to the polygon, and double-click to finish");
        } else if (source == freehandButton) {
            currentShape = null;
            currentPolygon = null;
            canvas.repaint();
            JOptionPane.showMessageDialog(this, "Hold down the mouse button to draw a freehand curve");
        }
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        if (currentPolygon != null) {
            if (e.getClickCount() == 2) {
                currentShape = new Polygon(currentPolygon.xpoints, currentPolygon.ypoints, currentPolygon.npoints);
                currentPolygon = null;
                canvas.repaint();
            } else {
                currentPolygon.addPoint(e.getX(), e.getY());
                canvas.repaint();
            }
        }
    }

    @Override
    public void mousePressed(MouseEvent e) {
        startPoint = e.getPoint();
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        endPoint = e.getPoint();
        if (currentShape == null) {
            if (lineButton.isSelected()) {
                currentShape = new Line2D.Double(startPoint, endPoint);
            } else if (rectButton.isSelected()) {
                currentShape = new Rectangle2D.Double(Math.min(startPoint.x, endPoint.x), Math.min(startPoint.y, endPoint.y),
                        Math.abs(endPoint.x - startPoint.x), Math.abs(endPoint.y - startPoint.y));
            } else if (ellipseButton.isSelected()) {
                currentShape = new Ellipse2D.Double(Math.min(startPoint.x, endPoint.x), Math.min(startPoint.y, endPoint.y),
                        Math.abs(endPoint.x - startPoint.x), Math.abs(endPoint.y - startPoint.y));
            }
        } else {
            currentShape = null;
        }
        canvas.repaint();
    }

    @Override
    public void mouseEntered(MouseEvent e) {

    }

    @Override
    public void mouseExited(MouseEvent e) {

    }

    @Override
    public void mouseDragged(MouseEvent e) {
        if (freehandButton.isSelected()) {
            Line2D line = new Line2D.Double(startPoint, e.getPoint());
            currentShape = line;
            startPoint = e.getPoint();
            canvas.repaint();
        }
    }

    @Override
    public void mouseMoved(MouseEvent e) {

    }

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

3. 连续播放图像：

import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;

public class ImagePlayer extends JFrame implements ActionListener {

    private JLabel imageLabel;
    private BufferedImage currentImage;
    private Timer timer;
    private int currentImageIndex;
    private File[] imageFiles;

    public ImagePlayer() {
        super("Image Player");

        // 选择图像文件夹
        JFileChooser fileChooser = new JFileChooser();
        fileChooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
        int result = fileChooser.showOpenDialog(this);
        if (result == JFileChooser.APPROVE_OPTION) {
            // 读取图像文件夹下的所有图像文件
            File imageFolder = fileChooser.getSelectedFile();
            imageFiles = imageFolder.listFiles((dir, name) -> name.endsWith(".jpg") || name.endsWith(".png"));
        } else {
            JOptionPane.showMessageDialog(this, "Please select an image folder");
            System.exit(0);
        }

        // 创建显示图像的标签
        imageLabel = new JLabel();
        add(imageLabel, BorderLayout.CENTER);

        // 创建计时器并启动
        timer = new Timer(1000, this);
        timer.start();

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(800, 600);
        setVisible(true);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        // 切换到下一张图像
        currentImageIndex = (currentImageIndex + 1) % imageFiles.length;
        try {
            currentImage = ImageIO.read(imageFiles[currentImageIndex]);
            imageLabel.setIcon(new ImageIcon(currentImage));
        } catch (IOException ex) {
            ex.printStackTrace();
        }
    }

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