java選擇排序視覺化
阿新 • • 發佈：2018-12-25
工具類
import java.awt.*;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Rectangle2D;
import java.lang.InterruptedException;
public class AlgoVisHelper {
private AlgoVisHelper(){}
public static final Color Red = new Color(0xF44336);
public static final Color Pink = new Color(0xE91E63 資料層
public class SelectionSortData {
private int[] numbers;
public int orderedIndex = -1; // [0...orderedIndex) 是有序的
public int currentCompareIndex = -1; // 當前正在比較的元素索引
public int currentMinIndex = -1; // 當前找到的最小元素的索引
public SelectionSortData(int N, int randomBound){
numbers = new int[N];
//準備資料
for( int i = 0 ; i < N ; i ++)
numbers[i] = (int)(Math.random()*randomBound) + 1;
}
public int N(){
return numbers.length;
}
public int get(int index){
if( index < 0 || index >= numbers.length)
throw new IllegalArgumentException("Invalid index to access Sort Data.");
return numbers[index];
}
public void swap(int i, int j) {
if( i < 0 || i >= numbers.length || j < 0 || j >= numbers.length)
throw new IllegalArgumentException("Invalid index to access Sort Data.");
int t = numbers[i];
numbers[i] = numbers[j];
numbers[j] = t;
}
}
檢視層
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class AlgoFrame extends JFrame{
private int canvasWidth;
private int canvasHeight;
public AlgoFrame(String title, int canvasWidth, int canvasHeight){
super(title);
this.canvasWidth = canvasWidth;
this.canvasHeight = canvasHeight;
AlgoCanvas canvas = new AlgoCanvas();
setContentPane(canvas);
pack();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setResizable(false);
setVisible(true);
}
public AlgoFrame(String title){
this(title, 1024, 768);
}
public int getCanvasWidth(){return canvasWidth;}
public int getCanvasHeight(){return canvasHeight;}
// data
private SelectionSortData data;
public void render(SelectionSortData data){
this.data = data;
repaint();
}
private class AlgoCanvas extends JPanel{
public AlgoCanvas(){
// 雙快取
super(true);
}
@Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D)g;
// 抗鋸齒
RenderingHints hints = new RenderingHints(
RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
g2d.addRenderingHints(hints);
// 具體繪製
int w = canvasWidth/data.N();
for(int i = 0 ; i < data.N() ; i ++ ) {
//判斷是否以排序
if (i < data.orderedIndex)
AlgoVisHelper.setColor(g2d, AlgoVisHelper.Red);
else
AlgoVisHelper.setColor(g2d, AlgoVisHelper.Grey);
//判斷是否是當前正在比較的元素索引
if(i == data.currentCompareIndex)
AlgoVisHelper.setColor(g2d, AlgoVisHelper.LightBlue);
//判斷是否當前找到的最小元素的索引
if(i == data.currentMinIndex)
AlgoVisHelper.setColor(g2d, AlgoVisHelper.Indigo);
AlgoVisHelper.fillRectangle(g2d, i * w, canvasHeight - data.get(i), w - 1, data.get(i));
}
}
@Override
public Dimension getPreferredSize(){
return new Dimension(canvasWidth, canvasHeight);
}
}
}控制層
import java.awt.EventQueue;
public class AlgoVisualizer {
private static int DELAY = 20;
private SelectionSortData data;
private AlgoFrame frame;
public AlgoVisualizer(int sceneWidth, int sceneHeight, int N){
//準備資料
data = new SelectionSortData(N, sceneHeight);
// 初始化檢視
EventQueue.invokeLater(() -> {
frame = new AlgoFrame("Selection Sort Visualization", sceneWidth, sceneHeight);
new Thread(() -> {
run();
}).start();
});
}
private void run(){
setData(0, -1, -1);
for( int i = 0 ; i < data.N() ; i ++ ){
// 尋找[i, n)區間裡的最小值的索引
int minIndex = i;
setData(i, -1, minIndex);
for( int j = i + 1 ; j < data.N() ; j ++ ){
setData(i, j, minIndex);
if( data.get(j) < data.get(minIndex) ){
minIndex = j;
setData(i, j, minIndex);
}
}
//根據陣列索引交換資料
data.swap(i , minIndex);
setData(i+1, -1, -1);
}
setData(data.N(),-1,-1);
}
//根據以排序、當前正在比較的元素索引和當前找到的最小元素的索引繪製圖形
private void setData(int orderedIndex, int currentCompareIndex, int currentMinIndex){
data.orderedIndex = orderedIndex;
data.currentCompareIndex = currentCompareIndex;
data.currentMinIndex = currentMinIndex;
frame.render(data);
AlgoVisHelper.pause(DELAY);
}
public static void main(String[] args) {
int sceneWidth = 800;
int sceneHeight = 800;
int N = 100;
AlgoVisualizer vis = new AlgoVisualizer(sceneWidth, sceneHeight, N);
}
}