递归解决汉诺塔问题[java/Eclipse]

package ui; import java.awt.Graphics; import java.awt.HeadlessException; import java.awt.Rectangle; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.FocusEvent; import java.awt.event.FocusListener; import java.util.ArrayList; import java.util.List; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.SwingUtilities; import logic.Pillar; public class WinMain extends JFrame { public static final int DISC_HEIGHT = 10;// 碟子的厚度 public static final int X = 30; public static final int Y = 150;// 柱子基部的Y坐标 private int speed = 100; private List list = new ArrayList(); private Pillar A = new Pillar(X + 80, Y, 0, "A");// 起始柱子 private Pillar B = new Pillar(X + 200, Y, 0, "B");// 经过柱子 private Pillar C = new Pillar(X + 320, Y, 0, "C");// 目标柱子 JButton button1 = new JButton("Go"); // 碟子的集合 Rectangle[] rects = new Rectangle[] { //new Rectangle(0, 0, 30, DISC_HEIGHT), //new Rectangle(0, 0, 50, DISC_HEIGHT), new Rectangle(0, 0, 70, DISC_HEIGHT), new Rectangle(0, 0, 90, DISC_HEIGHT), new Rectangle(0, 0, 110, DISC_HEIGHT) }; public WinMain() throws HeadlessException { super(); init(); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); this.setLocation(0, 0); this.setSize(450, 350); this.getContentPane().setLayout(null); this.getContentPane().add(button1); button1.setSize(200, 100); button1.setLocation(this.getWidth() / 2 - button1.getWidth() / 2, 200); button1.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent arg0) { init(); go(rects.length - 1, A, C); } }); this.addFocusListener(new FocusListener() { public void focusGained(FocusEvent arg0) { WinMain.this.repaint(); } public void focusLost(FocusEvent arg0) { } }); } @Override public void paint(Graphics g) { super.paint(g); int delt = 15; g.drawString(A.getName(), A.getX(), A.getY() + delt); g.drawString(B.getName(), B.getX(), B.getY() + delt); g.drawString(C.getName(), C.getX(), C.getY() + delt); for (Rectangle r : rects) { g.drawRect(r.x, r.y, (int) r.getWidth(), (int) r.getHeight()); } } /** * 设置初始位置 * */ private void init() { A.setNum(0); B.setNum(0); C.setNum(0); try { Thread.sleep(500); } catch (InterruptedException e) { e.printStackTrace(); } for (int i = rects.length - 1; i >= 0; i--) { addDiscToZhu(rects[i], A); } } /** * 把r加到目标柱子上 * * @param r * @param dest */ private void addDiscToZhu(Rectangle r, Pillar dest) { dest.setNum(dest.getNum() + 1); r.setLocation(dest.getX() - (int) r.getWidth() / 2, Y - dest.getNum() * WinMain.DISC_HEIGHT); } private Pillar getOher(Pillar a, Pillar b) { list.clear(); list.add(A); list.add(B); list.add(C); list.remove(a); list.remove(b); return (Pillar) list.get(0); } /** * 把0-i的元素从from移到to * * @param i * @param A * @param C */ private void go(int i, Pillar from, Pillar to) { if (i == 0) { moveTo(i, from, to); } else { go(i - 1, from, this.getOher(from, to)); moveTo(i, from, to); go(i - 1, this.getOher(from, to), to); } } /** * 将一个元素i从from移到to * * @param i * @param from * @param to */ private void moveTo(int i, Pillar from, Pillar to) { from.setNum(from.getNum() - 1); addDiscToZhu(rects[i], to); repaint(); this.update(this.getGraphics()); try { Thread.sleep(500 - speed); } catch (InterruptedException e) { e.printStackTrace(); } } public static void main(String[] args) { new Thread(new Runnable(){ public void run() { JFrame win = new WinMain(); win.setVisible(true); } }).start(); } }