可视化查找之二分查找
如果查找过程和程序执行能结合起来，那么这个过程会更加直观。
本文简单地实现了二分查找的可视化。界面很简单就包括两个部分：界面左侧是可视化查找部分，右侧是二分查找的代码。如下图所示：
程序的关键点主要有两点：
1. 如何在页面上表示出查找程序的运行过程。
2. 如何将排序程序的运行过程和可视化查找结合起来，保持状态一致。
我的解决方法如下：
我采用了JList去模拟程序的执行，JList有一个setSelectedIndex的方法，能高亮显示指定的行。通过改变selectedIndex的值，能够达到模拟程序执行的效果。根据模拟程序中保存的状态值去修改可视化查找。
程序主要是随机产生10个数值，查找数字9.
可以找到的运行情况：
找不到的运行情况：
程序代码如下：
程序代码也没有优化过，注释也基本上没有加，不好意思。大家如果有其它好的想法，请共享一下哦。
本文简单地实现了二分查找的可视化。界面很简单就包括两个部分：界面左侧是可视化查找部分，右侧是二分查找的代码。如下图所示：
程序的关键点主要有两点：
1. 如何在页面上表示出查找程序的运行过程。
2. 如何将排序程序的运行过程和可视化查找结合起来，保持状态一致。
我的解决方法如下：
我采用了JList去模拟程序的执行，JList有一个setSelectedIndex的方法，能高亮显示指定的行。通过改变selectedIndex的值，能够达到模拟程序执行的效果。根据模拟程序中保存的状态值去修改可视化查找。
程序主要是随机产生10个数值，查找数字9.
可以找到的运行情况：
找不到的运行情况：
程序代码如下：
package my.visualization.search.binary;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JRadioButtonMenuItem;
/**
*
* @author Eric
* @version 1.0
*
*/
public class BinarySearchVisualizationFrame extends JFrame {
private static final long serialVersionUID = -6725108659717827278L;
private Container contentPane;
/**
* 设置三个Menu Item，分别用于开始程序，调整运行的速度以及退出程序
*
*/
private JMenuItem startMI = new JMenuItem("Start");
private JMenu speedMenu = new JMenu("Speed");
private JMenuItem exitMI = new JMenuItem("Exit");
private JMenuItem aboutMI = new JMenuItem("About");
/**
* 设定5个速度级别
*/
private JRadioButtonMenuItem speedMI1 = new JRadioButtonMenuItem("Speed1",
true);
private JRadioButtonMenuItem speedMI2 = new JRadioButtonMenuItem("Speed2",
false);
private JRadioButtonMenuItem speedMI3 = new JRadioButtonMenuItem("Speed3",
false);
private JRadioButtonMenuItem speedMI4 = new JRadioButtonMenuItem("Speed4",
false);
private JRadioButtonMenuItem speedMI5 = new JRadioButtonMenuItem("Speed5",
false);
public int speedFlag = 1;
/**
* 冒泡排序可视化的Panel
*/
private BinarySearchPanel panel;
public BinarySearchVisualizationFrame(){
setTitle("可视化查找之二分查找");
setSize(700, 400);
setResizable(false);
JMenuBar menuBar = new JMenuBar();
setJMenuBar(menuBar);
JMenu setMenu = new JMenu("Set");
JMenu helpMenu = new JMenu("Help");
setMenu.setMnemonic('s');
setMenu.setMnemonic('H');
menuBar.add(setMenu);
menuBar.add(helpMenu);
setMenu.add(startMI);
setMenu.addSeparator();
setMenu.addSeparator();
setMenu.add(speedMenu);
setMenu.addSeparator();
setMenu.add(exitMI);
ButtonGroup group = new ButtonGroup();
group.add(speedMI1);
group.add(speedMI2);
group.add(speedMI3);
group.add(speedMI4);
group.add(speedMI5);
speedMenu.add(speedMI1);
speedMenu.add(speedMI2);
speedMenu.add(speedMI3);
speedMenu.add(speedMI4);
speedMenu.add(speedMI5);
startMI.addActionListener(new StartAction());
speedMI1.addActionListener(new SpeedAction());
speedMI2.addActionListener(new SpeedAction());
speedMI3.addActionListener(new SpeedAction());
speedMI4.addActionListener(new SpeedAction());
speedMI5.addActionListener(new SpeedAction());
exitMI.addActionListener(new ExitAction());
helpMenu.add(aboutMI);
aboutMI.addActionListener(new AboutAction());
contentPane = getContentPane();
panel = new BinarySearchPanel(this);
contentPane.add(panel);
startMI.setEnabled(true);
}
private class StartAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
startMI.setEnabled(false);
panel.timer.start();
}
}
private class ExitAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
System.exit(0);
}
}
private class SpeedAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
Object speed = event.getSource();
if (speed == speedMI1) {
speedFlag = 1;
} else if (speed == speedMI2) {
speedFlag = 2;
} else if (speed == speedMI3) {
speedFlag = 3;
} else if (speed == speedMI4) {
speedFlag = 4;
} else if (speed == speedMI5) {
speedFlag = 5;
}
panel.timer.setDelay(1000 - 200 * (speedFlag - 1));
}
}
private class AboutAction implements ActionListener {
public void actionPerformed(ActionEvent event) {
String string = "说明:\n1.本程序可视化二分查找的过程\n" + "2.查找的数字为9\n" + "3.low的颜色用PINK表示\n"
+ "4.high的颜色用CYAN表示\n" + "5.如果能找到，找到的数字用蓝色表示\n"+"6. 如果没有找到，颜色全部为绿色";
JOptionPane.showMessageDialog(BinarySearchVisualizationFrame.this, string);
}
}
}
package my.visualization.search.binary;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Random;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.Timer;
public class BinarySearchPanel extends JPanel {
private static final long serialVersionUID = -9149581857139587792L;
private static final String[] code = {
"public int binarySearch0(int[] a, int key) {",
" int low = 0;",
" int high = a.length - 1;",
" while (low <= high) {",
" int mid = (low + high) >>> 1; ",
" int midVal = a[mid]; ",
" if (midVal < key)",
" low = mid + 1; ",
" else if (midVal > key) ",
" high = mid - 1; ",
" else ",
" return mid; ",
" }",
" return -1",
"}" };
/**
* 初始化10个数据
*/
private List<NumberRectangle> numbers = initialNumberRectangles();
private JList codeList = new JList(code);;
public TimerAction timerAction;
public Timer timer;
public BinarySearchVisualizationFrame frame;
public BinarySearchPanel(BinarySearchVisualizationFrame frame) {
timerAction = new TimerAction();
timer = new Timer(1000, timerAction);
codeList.setSelectedIndex(1);
JScrollPane scrollPane1 = new JScrollPane(codeList);
this.setLayout(new BorderLayout());
this.add(scrollPane1, BorderLayout.EAST);
this.frame = frame;
}
/**
* 判断排序是否已经结束
*/
private boolean completed = false;
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
drawNumberRectangles(g2);
}
private void drawNumberRectangles(Graphics2D g2) {
for (NumberRectangle rectangle : numbers) {
rectangle.draw(g2);
}
}
int low = 0;
int high = 9;
int selectedIndex = 1;
int mid = 0;
int key = 9;
int midVal = 0;
private class TimerAction implements ActionListener, Serializable {
private static final long serialVersionUID = -8671813189049345697L;
public void actionPerformed(ActionEvent event) {
if (completed) {
return;
}
/**
* 为low 和 high着色
*/
switch (selectedIndex) {
case 1:
codeList.setSelectedIndex(selectedIndex++);
break;
case 2:
codeList.setSelectedIndex(selectedIndex++);
break;
case 3:
numbers.get(low).setColor(Color.PINK);
numbers.get(high).setColor(Color.CYAN);
//while(low <high)
codeList.setSelectedIndex(selectedIndex);
if (low <= high) {
selectedIndex++;
} else {
numbers.get(low).setColor(Color.GREEN);
numbers.get(high).setColor(Color.GREEN);
selectedIndex = 13;
}
break;
case 4:
codeList.setSelectedIndex(selectedIndex++);
mid = (low + high) >>> 1;
break;
case 5:
codeList.setSelectedIndex(selectedIndex++);
midVal = numbers.get(mid).getValue();
break;
case 6 :
codeList.setSelectedIndex(selectedIndex);
if(midVal < key){
selectedIndex = 7;
}else{
selectedIndex = 8;
}
break;
case 7:
codeList.setSelectedIndex(selectedIndex);
numbers.get(low).setColor(Color.GREEN);
low = mid+1;
selectedIndex = 3;
break;
case 8:
codeList.setSelectedIndex(selectedIndex);
if(midVal > key){
selectedIndex = 9;
}else{
selectedIndex = 10;
}
break;
case 9:
codeList.setSelectedIndex(selectedIndex);
numbers.get(high).setColor(Color.GREEN);
high = mid -1;
selectedIndex = 3;
break;
case 10:
codeList.setSelectedIndex(selectedIndex++);
break;
case 11:
codeList.setSelectedIndex(selectedIndex);
//mid的方格着色
completed = true;
numbers.get(low).setColor(Color.GREEN);
numbers.get(high).setColor(Color.GREEN);
numbers.get(mid).setColor(Color.BLUE);
break;
case 13:
codeList.setSelectedIndex(selectedIndex);
completed = true;
break;
default:
break;
}
repaint();
}
}
private List<NumberRectangle> initialNumberRectangles() {
List<NumberRectangle> list = new ArrayList<NumberRectangle>();
/**
* 随机产生10个数组
*/
Random random = new Random();
int[] values = new int[10];
for (int i = 1; i <= 10; i++) {
//list.add(new NumberRectangle(i,1,random.nextInt(15)+1, Color.GREEN));
values[i - 1] = random.nextInt(15) + 1;
}
Arrays.sort(values);
for (int i = 1; i <= 10; i++) {
list.add(new NumberRectangle(i, 1, values[i - 1], Color.GREEN));
}
return list;
}
}
package my.visualization.search.binary;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.Rectangle2D;
public class NumberRectangle {
private int x;
private int y;
private int value;
private Color color;
public NumberRectangle() {
}
public NumberRectangle(int x, int y, int value, Color color) {
this.x = x;
this.y = y;
this.color = color;
this.value = value;
}
public void draw(Graphics2D g2) {
int clientX = 30 + x * 30;
int clientY = 20 + y * 10;
Rectangle2D.Double rect = new Rectangle2D.Double(clientX, clientY, 20,
value * 20);
g2.setPaint(color);
g2.fill(rect);
g2.setPaint(Color.BLACK);
g2.draw(rect);
g2.drawString(String.valueOf(value), clientX, clientY - 10);
}
/**
* @return the color
*/
public Color getColor() {
return color;
}
/**
* @param color
* the color to set
*/
public void setColor(Color color) {
this.color = color;
}
/**
* @return the x
*/
public int getX() {
return x;
}
/**
* @param x
* the x to set
*/
public void setX(int x) {
this.x = x;
}
/**
* @return the y
*/
public int getY() {
return y;
}
/**
* @param y
* the y to set
*/
public void setY(int y) {
this.y = y;
}
/**
* @return the value
*/
public int getValue() {
return value;
}
/**
* @param value
* the value to set
*/
public void setValue(int value) {
this.value = value;
}
}
package my.visualization.search.binary;
import javax.swing.JFrame;
public class SortApplication {
@SuppressWarnings("deprecation")
public static void main(String[] args) {
BinarySearchVisualizationFrame frame = new BinarySearchVisualizationFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.show();
}
}
程序代码也没有优化过，注释也基本上没有加，不好意思。大家如果有其它好的想法，请共享一下哦。