java编程例子源码(狐狸与兔子)

-------------------------------------------- animal package animal;

import java.util.ArrayList;

import field.Location;

public abstract class Animal {

private int ageLimit;

private int breedableAge;

private int age;

private boolean isAlive = true;

public Animal(int ageLimit, int breedableAge) { this.ageLimit = ageLimit;

this.breedableAge = breedableAge;

}

protected int getAge() {

return age;

}

protected double getAgePercent() {

return (double)age/ageLimit;

}

public abstract Animal breed();

public void grow() {

age++;

if ( age >= ageLimit ) {

die();

}

}

public void die() {

isAlive = false;

}

public boolean isAlive() {

return isAlive;

}

public boolean isBreedable() {

return age >= breedableAge;

}

public Location move(Location[] freeAdj) {

Location ret = null;

if ( freeAdj.length>0 && Math.random() < 0.02 ) { ret =

freeAdj[(int)(Math.random()*freeAdj.length)];

}

return ret;

}

@Override

public String toString() {

return ""+age+":"+(isAlive?"live":"dead");

}

public Animal feed(ArrayList neighbour) { return null;

}

protected void longerLife(int inc) {

ageLimit += inc;

}

}

----------------------------------------------- Cell

package cell;

import java.awt.Graphics;

public interface Cell {

void draw(Graphics g, int x, int y, int size);

}

----------------------------------------------- Location package field;

public class Location {

private int row;

private int col;

public Location(int row, int col) {

this.row = row;

this.col = col;

}

public int getRow() { return row; }

public int getCol() { return col; }

}

----------------------------------------------- Fox

package animal;

import java.awt.Color;

import java.awt.Graphics;

import java.util.ArrayList;

import cell.Cell;

public class Fox extends Animal implements Cell { public Fox() {

super(20,4);

}

@Override

public void draw(Graphics g, int x, int y, int size) { int alpha = (int)((1-getAgePercent())*255);

g.setColor(new Color(0, 0, 0,

alpha));//(int)((20-getAge())/20.0*255)));

g.fillRect(x, y, size, size);

}

@Override

public Animal breed() {

Animal ret = null;

if ( isBreedable() && Math.random() < 0.05 ) {

ret = new Fox();

}

return ret;

}

@Override

public String toString() {

return "Fox:"+super.toString();

}

@Override

public Animal feed(ArrayList neighbour) { Animal ret = null;

if ( Math.random()< 0.2 ) {

ret =

neighbour.get((int)(Math.random()*neighbour.size()));

longerLife(2);

}

return ret;

}

}

---------------------------------------------- Rabbit package animal;

import java.awt.Color;

import java.awt.Graphics;

import cell.Cell;

public class Rabbit extends Animal implements Cell { public Rabbit() {

super(10,2);

}

@Override

public void draw(Graphics g, int x, int y, int size) { int alpha = (int)((1-getAgePercent())*255);

g.setColor(new Color(255, 0, 0, alpha));

g.fillRect(x, y, size, size);

}

@Override

public Animal breed() {

Animal ret = null;

if ( isBreedable() && Math.random() < 0.12 ) {

ret = new Rabbit();

}

return ret;

}

@Override

public String toString() {

return "Rabbit:"+super.toString();

}

}

----------------------------------------- View

package field;

import java.awt.Color;

import java.awt.Dimension;

import java.awt.Graphics;

import javax.swing.JPanel;

import cell.Cell;

public class View extends JPanel {

private static final long serialVersionUID = -2417015700213488315L;

private static final int GRID_SIZE = 16;

private Field theField;

public View(Field field) {

theField = field;

}

@Override

public void paint(Graphics g) {

super.paint(g);

g.setColor(Color.GRAY);

for ( int row = 0; row

g.drawLine(0, row*GRID_SIZE, theField.getWidth()*GRID_SIZE, row*GRID_SIZE);

}

for ( int col = 0; col

g.drawLine(col*GRID_SIZE, 0, col*GRID_SIZE, theField.getHeight()*GRID_SIZE);

}

for ( int row = 0; row

for ( int col = 0; col

Cell cell = theField.get(row, col);

if ( cell != null ) {

cell.draw(g, col*GRID_SIZE, row*GRID_SIZE, GRID_SIZE);

}

}

}

}

@Override

public Dimension getPreferredSize() {

return new Dimension(theField.getWidth()*GRID_SIZE+1, theField.getHeight()*GRID_SIZE+1);

}

}

----------------------------------------------- Field

package field;

import java.util.ArrayList;

import cell.Cell;

public class Field {

private static final Location[] adjacent = {

new Location(-1,-1),new Location(-1,0),new Location(-1,1),

new Location(0,-1), new Location(0,0), new Location(0,1),

new Location(1,-1), new Location(1,0), new Location(1,1)

};

private int width;

private int height;

private Cell[][] field;

public Field(int width, int height) {

this.width = width;

this.height = height;

field = new Cell[height][width];

}

public int getWidth() { return width; }

public int getHeight() { return height; }

public Cell place(int row, int col, Cell o) {

Cell ret = field[row][col];

field[row][col] = o;

return ret;

}

public Cell get(int row, int col) {

return field[row][col];

}

public Cell[] getNeighbour(int row, int col) {

ArrayList list = new ArrayList();

for ( int i=-1; i<2; i++ ) {

for ( int j=-1; j<2; j++ ) {

int r = row+i;

int c = col+j;

if ( r >-1 && r-1 && c

list.add(field[r][c]);

}

}

}

return list.toArray(new Cell[list.size()]);

}

public Location[] getFreeNeighbour(int row, int col) {

ArrayList list = new ArrayList();

for ( Location loc : adjacent ) {

int r = row+loc.getRow();

int c = col+loc.getCol();

if ( r >-1 && r-1 && c

}

}

return list.toArray(new Location[list.size()]);

}

public boolean placeRandomAdj(int row, int col, Cell cell) {

boolean ret = false;

Location[] freeAdj = getFreeNeighbour(row, col);

if ( freeAdj.length >0 ) {

int idx = (int)(Math.random()*freeAdj.length);

field[freeAdj[idx].getRow()][freeAdj[idx].getCol()] = cell;

ret = true;

}

return ret;

}

public Cell remove(int row, int col) {

Cell ret = field[row][col];

field[row][col] = null;

return ret;

}

public void remove(Cell cell) {

for ( int row = 0; row < height; row++ ) {

for ( int col = 0; col < width; col++ ) {

if ( field[row][col] == cell ) {

field[row][col] = null;

break;

}

}

}

}

public void clear() {

for ( int i=0; i

for ( int j=0; j

field[i][j] = null;

}

}

}

public void move(int row, int col, Location loc) {

field[loc.getRow()][loc.getCol()] = field[row][col];

remove(row, col);

}

}

----------------------------------------------- FoxAndRabbit

package foxnrabbit;

import java.util.ArrayList;

import javax.swing.JFrame;

import animal.Animal;

import animal.Fox;

import animal.Rabbit;

import cell.Cell;

import field.Field;

import field.Location;

import field.View;

public class FoxAndRabbit {

private Field theField;

private View theView;

public FoxAndRabbit(int size) {

theField = new Field(size, size);

for ( int row = 0; row

for ( int col = 0; col

double probability = Math.random();

if ( probability < 0.05 ) {

theField.place(row, col, new Fox());

} else if ( probability < 0.15 ) {

theField.place(row, col, new Rabbit());

}

}

}

theView = new View(theField);

JFrame frame = new JFrame();

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

frame.setResizable(false);

frame.setTitle("Cells");

frame.add(theView);

frame.pack();

frame.setVisible(true);

}

public void start(int steps) {

for ( int i=0; i

step();

theView.repaint();

try {

Thread.sleep(200);

} catch (InterruptedException e) {

e.printStackTrace();

}

}

}

public void step() {

for ( int row = 0; row< theField.getHeight(); row++ ) {

for ( int col = 0; col < theField.getWidth(); col++ ) {

Cell cell = theField.get(row, col);

if ( cell != null ) {

Animal animal = (Animal)cell;

animal.grow();

if ( animal.isAlive() ) {

// move

Location loc = animal.move(theField.getFreeNeighbour(row, col));

if ( loc != null ) {

theField.move(row, col, loc);

}

// eat

// animal.eat(theField);

Cell[] neighbour = theField.getNeighbour(row, col);

ArrayList listRabbit = new ArrayList();

for ( Cell an : neighbour ) {

if ( an instanceof Rabbit ) {

listRabbit.add((Rabbit)an);

}

}

if ( !listRabbit.isEmpty() ) {

Animal fed = animal.feed(listRabbit);

if ( fed != null ) {

theField.remove((Cell)fed);

}

}

// breed

Animal baby = animal.breed();

if ( baby != null ) {

theField.placeRandomAdj(row, col, (Cell)baby);

}

} else {

theField.remove(row, col);

}

}

}

}

}

public static void main(String[] args) {

FoxAndRabbit fnr = new FoxAndRabbit(50);

fnr.start(100);

}

}