java - 在 MySql 中存储形状

Question

我正在尝试将形状插入我的 mysql。

有什么方法可以将形状保存到我的数据库中。 稍后可以恢复。

import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import com.mysql.jdbc.PreparedStatement;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.sql.Connection;
import java.util.LinkedList;
import java.util.List;

公共(public)类 MyApp 扩展 JFrame 实现 ChangeListener {

private static final long serialVersionUID = 1L;
private JPanel contentPane;
private List<Shape> shapes;
private Canvas canvas;
Shape shapeObject = null;
// private JButton btnClear;
private JColorChooser cc;
private JButton btnLoad;
private JButton btnSave;

Connection con;
PreparedStatement ps;

公共(public)MyApp(){

    setResizable(false);

    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    setBounds(100, 100, 1348, 660);
    contentPane = new JPanel();
    contentPane.setBackground(Color.LIGHT_GRAY);
    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
    setContentPane(contentPane);
    contentPane.setLayout(null);

    JRadioButton[] shape = getShapesRadioButtons();
    for (int i = 0; i < shape.length; i++) {
        this.getContentPane().add(shape[i]);
    }
    JCheckBox[] color = getColor();
    for (int i = 0; i < color.length; i++) {
        this.getContentPane().add(color[i]);
    }

    canvas = new Canvas();
    canvas.setBackground(Color.WHITE);
    canvas.setBounds(608, 56, 724, 565);
    contentPane.add(canvas);


    canvas.addMouseListener(new MouseListener() {

        @Override
        public void mouseReleased(MouseEvent mr) {
            // TODO Auto-generated method stub

            shapeObject.pos.x1 = mr.getX();
            shapeObject.pos.y1 = mr.getY();
            shapeObject.pos.calculate();

            if (shapeObject.pos.x > shapeObject.pos.x1) {
                shapeObject.pos.x2 = shapeObject.pos.x;
                shapeObject.pos.x = shapeObject.pos.x1;
                shapeObject.pos.x1 = shapeObject.pos.x2;
            }
            if (shapeObject.pos.y > shapeObject.pos.y1) {
                shapeObject.pos.y2 = shapeObject.pos.y;
                shapeObject.pos.y = shapeObject.pos.y1;
                shapeObject.pos.y1 = shapeObject.pos.y2;
            }

            shapes.add(shapeObject);
            repaint();
        }

        @Override
        public void mousePressed(MouseEvent e) {
            // TODO Auto-generated method stub

            shapeObject.pos.x = e.getX();
            shapeObject.pos.y = e.getY();

        }

        @Override
        public void mouseExited(MouseEvent e) {
            // TODO Auto-generated method stub

        }

        @Override
        public void mouseEntered(MouseEvent e) {
            // TODO Auto-generated method stub

        }

        @Override
        public void mouseClicked(MouseEvent event) {

        }

    });

    // Add Shapes jButtons

    shapes = new LinkedList<>();

    cc = new JColorChooser(canvas.getForeground());
    cc.setBounds(10, 267, 592, 354);
    cc.getSelectionModel().addChangeListener(this);
    contentPane.add(cc);

    btnSave = new JButton("Save");
    btnSave.setBounds(513, 243, 89, 23);
    btnSave.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            // TODO Auto-generated method stub
        }
    });
    contentPane.add(btnSave);

}

private ActionListener createActionListener(String shapeType) {
    ActionListener al = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            if (shapeType.equalsIgnoreCase("Circle")) {
                shapeObject = new Circle();
            } else if (shapeType.equalsIgnoreCase("Square")) {
                shapeObject = new Square();
            } else if (shapeType.equalsIgnoreCase("Rectangle")) {
                shapeObject = new Rectangle();
            } else if (shapeType.equalsIgnoreCase("Line")) {
                shapeObject = new Line();
            }
        }
    };
    return al;
}

private ActionListener getColor(String color) {
    ActionListener a = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            if (color.equalsIgnoreCase("White")) {
                canvas.setBackground(Color.white);
            } else if (color.equalsIgnoreCase("Black")) {
                canvas.setBackground(Color.black);
            } else if (color.equalsIgnoreCase("Red")) {
                canvas.setBackground(Color.red);
            } else if (color.equalsIgnoreCase("Blue")) {
                canvas.setBackground(Color.blue);
            } else if (color.equalsIgnoreCase("Green")) {
                canvas.setBackground(Color.green);
            } else if (color.equalsIgnoreCase("Yellow")) {
                canvas.setBackground(Color.yellow);
            }
            repaint();
        }
    };
    return a;
}

私有(private) JCheckBox[] getColor() {

    JCheckBox[] color = new JCheckBox[6];
    color[0] = new JCheckBox("White");
    color[0].setBounds(500, 200, 20, 20);
    color[0].addActionListener(getColor("White"));
    color[0].setBackground(Color.white);

    color[1] = new JCheckBox("Black");
    color[1].setBounds(520, 200, 20, 20);
    color[1].addActionListener(getColor("Black"));
    color[1].setBackground(Color.black);

    color[2] = new JCheckBox("Red");
    color[2].setBounds(540, 200, 20, 20);
    color[2].addActionListener(getColor("Red"));
    color[2].setBackground(Color.red);

    color[3] = new JCheckBox("Blue");
    color[3].setBounds(500, 220, 20, 20);
    color[3].addActionListener(getColor("Blue"));
    color[3].setBackground(Color.blue);

    color[4] = new JCheckBox("Green");
    color[4].setBounds(520, 220, 20, 20);
    color[4].addActionListener(getColor("Green"));
    color[4].setBackground(Color.green);

    color[5] = new JCheckBox("Yellow");
    color[5].setBounds(540, 220, 20, 20);
    color[5].addActionListener(getColor("Yellow"));
    color[5].setBackground(Color.yellow);

    ButtonGroup bg = new ButtonGroup();
    bg.add(color[0]);
    bg.add(color[1]);
    bg.add(color[2]);
    bg.add(color[3]);
    bg.add(color[4]);
    bg.add(color[5]);

    return color;

}

私有(private) JRadioButton[] getShapesRadioButtons() { JRadioButton[] 形状 = new JRadioButton[4];

    shape[0] = new JRadioButton("Circle");
    shape[0].addActionListener(createActionListener("Circle"));
    shape[0].getColorModel();
    shape[0].setBounds(10, 200, 60, 60);

    shape[1] = new JRadioButton("Square");
    shape[1].addActionListener(createActionListener("Square"));
    shape[1].setBounds(70, 200, 80, 60);

    shape[2] = new JRadioButton("Rectangle");
    shape[2].addActionListener(createActionListener("Rectangle"));
    shape[2].setBounds(150, 200, 100, 60);

    shape[3] = new JRadioButton("Line");
    shape[3].addActionListener(createActionListener("Line"));
    shape[3].setBounds(250, 200, 80, 60);

    ButtonGroup bg = new ButtonGroup();
    bg.add(shape[0]);
    bg.add(shape[1]);
    bg.add(shape[2]);
    bg.add(shape[3]);

    return shape;
}

@Override
public void stateChanged(ChangeEvent arg0) {
    // TODO Auto-generated method stub
    Color newColor = cc.getColor();
    canvas.setForeground(newColor);
    repaint();
}

@Override
public void paint(Graphics g) {
    super.paint(g);

    for (Shape shape : shapes) {
        shape.paintComponent((Graphics2D) canvas.getGraphics());

    }

    /*
     * for (int i = 0; i < shapes.size(); i++) { Shape shape =
     * shapes.get(i);
     * shape.paintComponent((Graphics2D)canvas.getGraphics()); }
     */}}

还有一些用于计算和绘制形状的类

Answer 1

我想说，一种选择是使要保留在数据库中的对象可序列化，然后将它们存储在 BLOB 列中。

您会在网上找到很多有关序列化的教程，这只是其中之一:https://www.tutorialspoint.com/java/java_serialization.htm