用Java制作一个简易的画图程序，要求有七种颜色，有矩形，直线，椭圆

好的，以下是一个简单的Java画图程序，包含七种颜色，可以绘制矩形、直线、椭圆。

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

public class SimplePaint extends JFrame implements ActionListener, MouseListener, MouseMotionListener {
    private int startX, startY, endX, endY;
    private int currentShape;
    private int currentColor;
    private JButton[] colorButtons;
    private JButton[] shapeButtons;
    private JPanel colorPanel;
    private JPanel shapePanel;
    private JPanel controlPanel;
    private DrawingArea drawingArea;

    public SimplePaint() {
        setTitle("Simple Paint");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(600, 400);

        // 初始化画布和颜色、形状按钮
        drawingArea = new DrawingArea();
        colorButtons = new JButton[7];
        colorButtons[0] = new JButton("Black");
        colorButtons[1] = new JButton("Red");
        colorButtons[2] = new JButton("Orange");
        colorButtons[3] = new JButton("Yellow");
        colorButtons[4] = new JButton("Green");
        colorButtons[5] = new JButton("Blue");
        colorButtons[6] = new JButton("Purple");
        for (int i = 0; i < colorButtons.length; i++) {
            colorButtons[i].addActionListener(this);
        }
        shapeButtons = new JButton[3];
        shapeButtons[0] = new JButton("Rectangle");
        shapeButtons[1] = new JButton("Line");
        shapeButtons[2] = new JButton("Oval");
        for (int i = 0; i < shapeButtons.length; i++) {
            shapeButtons[i].addActionListener(this);
        }

        // 设置颜色、形状按钮面板
        colorPanel = new JPanel();
        colorPanel.setLayout(new GridLayout(1, colorButtons.length));
        for (int i = 0; i < colorButtons.length; i++) {
            colorPanel.add(colorButtons[i]);
        }
        shapePanel = new JPanel();
        shapePanel.setLayout(new GridLayout(1, shapeButtons.length));
        for (int i = 0; i < shapeButtons.length; i++) {
            shapePanel.add(shapeButtons[i]);
        }

        // 设置控制面板
        controlPanel = new JPanel();
        controlPanel.setLayout(new BorderLayout());
        controlPanel.add(colorPanel, BorderLayout.NORTH);
        controlPanel.add(shapePanel, BorderLayout.SOUTH);

        // 添加组件
        add(drawingArea, BorderLayout.CENTER);
        add(controlPanel, BorderLayout.NORTH);

        // 添加鼠标事件监听器
        drawingArea.addMouseListener(this);
        drawingArea.addMouseMotionListener(this);
    }

    public void actionPerformed(ActionEvent e) {
        // 处理颜色按钮事件
        for (int i = 0; i < colorButtons.length; i++) {
            if (e.getSource() == colorButtons[i]) {
                currentColor = i;
                return;
            }
        }
        // 处理形状按钮事件
        for (int i = 0; i < shapeButtons.length; i++) {
            if (e.getSource() == shapeButtons[i]) {
                currentShape = i;
                return;
            }
        }
    }

    public void mouseClicked(MouseEvent e) {}
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e) {}
    public void mousePressed(MouseEvent e) {
        startX = e.getX();
        startY = e.getY();
    }
    public void mouseReleased(MouseEvent e) {
        endX = e.getX();
        endY = e.getY();
        // 绘制形状
        Graphics g = drawingArea.getGraphics();
        g.setColor(getColor(currentColor));
        switch (currentShape) {
            case 0: // 矩形
                g.drawRect(Math.min(startX, endX), Math.min(startY, endY), Math.abs(endX - startX), Math.abs(endY - startY));
                break;
            case 1: // 直线
                g.drawLine(startX, startY, endX, endY);
                break;
            case 2: // 椭圆
                g.drawOval(Math.min(startX, endX), Math.min(startY, endY), Math.abs(endX - startX), Math.abs(endY - startY));
                break;
        }
        g.dispose();
    }
    public void mouseDragged(MouseEvent e) {}
    public void mouseMoved(MouseEvent e) {}

    private Color getColor(int index) {
        switch (index) {
            case 0: // 黑色
                return Color.BLACK;
            case 1: // 红色
                return Color.RED;
            case 2: // 橙色
                return Color.ORANGE;
            case 3: // 黄色
                return Color.YELLOW;
            case 4: // 绿色
                return Color.GREEN;
            case 5: // 蓝色
                return Color.BLUE;
            case 6: // 紫色
                return new Color(128, 0, 128);
            default:
                return Color.BLACK;
        }
    }

    public static void main(String[] args) {
        SimplePaint paint = new SimplePaint();
        paint.setVisible(true);
    }

    // 画布面板
    class DrawingArea extends JPanel {
        public DrawingArea() {
            setPreferredSize(new Dimension(400, 300));
            setBackground(Color.WHITE);
        }
    }
}

这个程序使用了Java的Swing图形库，创建了一个窗口，在窗口中添加了一个画布和颜色、形状按钮。通过鼠标事件监听器实现了绘制矩形、直线、椭圆的功能，通过颜色按钮实现了七种颜色的选择。您可以根据需要对程序进行修改和完善。