import java.awt.image.BufferedImage;
import javax.imageio.ImageIO;
import java.awt.Graphics;/** 飞行物 */
public abstract class FlyingObject {protected int width;protected int height;protected int x;protected int y;public static final int LIFE = 0;public static final int DEAD = 1;public static final int REMOVE = 2;protected int state = LIFE;public abstract void step();public abstract BufferedImage getImage();public void paint(Graphics g){g.drawImage(getImage(),x,y,null);}public boolean isLife(){return state==LIFE;}public boolean isDead(){return state==DEAD;}public boolean isRemove(){return state==REMOVE;}public void goDead(){state = DEAD;}public boolean hit(FlyingObject other){int x1 = this.x-other.width;int x2 = this.x+this.width;int y1 = this.y-other.height;int y2 = this.y+this.height;int x = other.x;int y = other.y;return x>=x1 && x<=x2 && y>=y1 && y<=y2;}public abstract boolean outOfBounds();
}

public interface Award {public int DOUBLE_FIRE = 0;public int LIFE = 1;public int getType();
}```java得分接口
public interface Enemy {public int getScore();
}```java敌机源码
import java.awt.image.BufferedImage;/** 小敌机 */
public class Airplane extends FlyingObject implements Enemy {private int step;/** 构造方法 */public Airplane(){width = 48;height = 50;x = (int)(Math.random()*(World.WIDTH-this.width));y = -this.height;step = 2; //移动速度}/** 小敌机走步step() */public void step(){y+=step;}int deadIndex = 1;public BufferedImage getImage(){if(isLife()){return Images.airplanes[0];}else if(isDead()){BufferedImage img = Images.airplanes[deadIndex++];if(deadIndex==Images.airplanes.length){state = REMOVE;}return img;}return null;}public int getScore(){return 1;}public boolean outOfBounds(){return this.y>=World.HEIGHT;}}

大敌机源码

import java.awt.image.BufferedImage;
/** 大敌机 */
public class BigAirplane extends FlyingObject implements Enemy {private int step;/** 构造方法 */public BigAirplane(){width = 66;height = 89;x = (int)(Math.random()*(World.WIDTH-this.width));y = -this.height;step = 2;}/** 大敌机走步step() */public void step(){y+=step;}int deadIndex = 1;public BufferedImage getImage(){if(isLife()){return Images.bigairplanes[0];}else if(isDead()){BufferedImage img = Images.bigairplanes[deadIndex++];if(deadIndex==Images.bigairplanes.length){state = REMOVE;}return img;}return null;}public int getScore(){return 3;}public boolean outOfBounds(){return this.y>=World.HEIGHT;}
}

小蜜蜂源码

import java.awt.image.BufferedImage;
/** 小蜜蜂 */
public class Bee extends FlyingObject implements Award {private int xStep; //x坐标走步private int yStep; //y坐标走步private int awardType; //奖励类型/** 构造方法 */public Bee(){width = 60;height = 51;x = (int)(Math.random()*(World.WIDTH-this.width));y = -this.height;xStep = 1;yStep = 2;awardType = (int)(Math.random()*2);}/** 蜜蜂走步step() */public void step(){x+=xStep;y+=yStep;if(x>=World.WIDTH-this.width || x<=0){xStep*=-1;}}int deadIndex = 1;public BufferedImage getImage(){if(isLife()){return Images.bees[0];}else if(isDead()){BufferedImage img = Images.bees[deadIndex++];if(deadIndex==Images.bees.length){state = REMOVE;}return img;}return null;}public int getType(){return awardType;}public boolean outOfBounds(){return this.y>=World.HEIGHT;}
}

子弹源码

import java.awt.image.BufferedImage;
/** 子弹 */
public class Bullet extends FlyingObject  {private int step;/** 构造方法 */public Bullet(int x,int y){width = 8;height = 20;this.x = x;this.y = y;step = 3;}/** 子弹走步step() */public void step(){y-=step;}public BufferedImage getImage(){if(isLife()){return Images.bullet;}if(isDead()){state = REMOVE;}return null;}public boolean outOfBounds(){return this.y<=-this.height;}
}

英雄级源码

import java.awt.image.BufferedImage;
/** 英雄机 */
public class Hero extends FlyingObject  {private int life; //命private int doubleFire; //火力值/** 构造方法 */public Hero(){width = 97;height = 139;x = 140;y = 400;life = 3;doubleFire = 0;}public void step(){}/** 英雄机随着鼠标动   x:鼠标的x坐标  y:鼠标的y坐标 */public void moveTo(int x,int y){this.x = x-this.width/2;this.y = y-this.height/2;}private int index = 0;public BufferedImage getImage(){if(isLife()){return Images.heros[index++%Images.heros.length];}return null;}public Bullet[] shoot(){int xStep = this.width/4;int yStep = 20;if(doubleFire>0){Bullet[] bs = new Bullet[2];bs[0] = new Bullet(this.x+1*xStep,this.y-yStep);bs[1] = new Bullet(this.x+3*xStep,this.y-yStep);doubleFire-=2;return bs;}else{Bullet[] bs = new Bullet[1];bs[0] = new Bullet(this.x+2*xStep,this.y-yStep);return bs;}}public void addLife(){life++;}public void addDoubleFire(){doubleFire+=40;}public int getLife(){return life;}public void subtractLife(){life--;}public int getDoubleFire(){return doubleFire;}public void clearDoubleFire(){doubleFire = 0;}public boolean outOfBounds(){return false;}}

初始化图片

import java.awt.image.BufferedImage;import javax.imageio.ImageIO;/** 图片工具类 */
public class Images {public static BufferedImage sky;public static BufferedImage bullet;public static BufferedImage[] airplanes;public static BufferedImage[] bigairplanes;public static BufferedImage[] bees;public static BufferedImage[] heros;static{sky = loadImage("background.png");bullet = loadImage("bullet.png");airplanes = new BufferedImage[5];airplanes[0] = loadImage("airplane0.png");bigairplanes = new BufferedImage[5];bigairplanes[0] = loadImage("bigairplane0.png");bees = new BufferedImage[5];bees[0] = loadImage("bee0.png");for(int i=1;i<airplanes.length;i++){airplanes[i] = loadImage("bom"+i+".png");bigairplanes[i] = loadImage("bom"+i+".png");bees[i] = loadImage("bom"+i+".png");}heros = new BufferedImage[2];for(int i=0;i<heros.length;i++){heros[i] = loadImage("hero"+i+".png");}}public static BufferedImage loadImage(String fileName){try{BufferedImage img = ImageIO.read(FlyingObject.class.getResource(fileName));return img;}catch(Exception e){e.printStackTrace();throw new RuntimeException();}}}

天空源码

import java.awt.image.BufferedImage;
import java.awt.Graphics;/** 天空 */
public class Sky extends FlyingObject  {private int step;private int y1; //天空移动/** 构造方法 */public Sky(){width = World.WIDTH;height = World.HEIGHT;x = 0;y = 0;step = 1;y1 = -this.height;}/** 天空走步step() */public void step(){y+=step;y1+=step;if(y>=this.height){y=-this.height;}if(y1>=this.height){y1=-this.height;}}public BufferedImage getImage(){return Images.sky;}public void paint(Graphics g){g.drawImage(getImage(),x,y,null);g.drawImage(getImage(),x,y1,null);}public boolean outOfBounds(){return false;}}

界面

import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Graphics;
import java.util.Arrays;
import java.util.Random;
import java.util.Timer;
import java.util.TimerTask;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;/** 世界 */
public class World extends JPanel{public static final int WIDTH = 400;public static final int HEIGHT = 700;private Sky sky = new Sky();private Hero hero = new Hero();private FlyingObject[] enemies = {}; //敌人数组private Bullet[] bullets = {}; //子弹数组public static final int START = 0;public static final int RUNNING = 1;public static final int PAUSE = 2;public static final int GAME_OVER = 3;private int state = START;public static BufferedImage start;public static BufferedImage pause;public static BufferedImage gameover;static{start = Images.loadImage("start.png");pause = Images.loadImage("pause.png");gameover = Images.loadImage("gameover.png");}public FlyingObject nextOne(){Random rand = new Random();int type = rand.nextInt(20);if(type < 5){return new Bee();}else if(type < 12){return new Airplane();}else{return new BigAirplane();}}int flyEnterIndex = 0;public void enterAction(){flyEnterIndex++;if(flyEnterIndex%1==0){FlyingObject obj = nextOne();enemies = Arrays.copyOf(enemies,enemies.length+1);enemies[enemies.length-1] = obj;}}public void stepAction(){sky.step();for(int i=0;i<enemies.length;i++){enemies[i].step();}for(int i=0;i<bullets.length;i++){bullets[i].step();}}int shootIndex = 0;public void shootAction(){shootIndex++;if(shootIndex%3==0){Bullet[] bs = hero.shoot();bullets = Arrays.copyOf(bullets,bullets.length+bs.length);System.arraycopy(bs,0,bullets,bullets.length-bs.length,bs.length);}}private int score = 0;public void bangAction(){for(int i=0;i<bullets.length;i++){Bullet b = bullets[i];for(int j=0;j<enemies.length;j++){FlyingObject f = enemies[j];if(b.isLife() && f.isLife() && b.hit(f)){b.goDead();f.goDead();if(f instanceof Enemy){Enemy e = (Enemy)f;score += e.getScore();}if(f instanceof Award){Award a = (Award)f;int type = a.getType();switch(type){case Award.DOUBLE_FIRE:hero.addDoubleFire();break;case Award.LIFE:hero.addLife();break;}}}}}}public void outOfBoundsAction(){int index = 0;FlyingObject[] enemyLives = new FlyingObject[enemies.length];for(int i=0;i<enemies.length;i++){FlyingObject e = enemies[i];if(!e.outOfBounds() && !e.isRemove()){enemyLives[index++] = e;}}enemies = Arrays.copyOf(enemyLives,index);index = 0;Bullet[] bulletLives = new Bullet[bullets.length];for(int i=0;i<bullets.length;i++){Bullet b = bullets[i];if(!b.outOfBounds() && !b.isRemove()){bulletLives[index++] = b;}}bullets = Arrays.copyOf(bulletLives,index);}public void hitAction(){for(int i=0;i<enemies.length;i++){FlyingObject f = enemies[i];if(f.isLife() && hero.isLife() && hero.hit(f)){f.goDead();hero.subtractLife();hero.clearDoubleFire();}}}public void checkGameOverAction(){if(hero.getLife()<=0){state = GAME_OVER;}}int num = 1;public void action(){ //启动执行MouseAdapter l = new MouseAdapter(){public void mouseMoved(MouseEvent e){if(state==RUNNING){int x = e.getX();int y = e.getY();hero.moveTo(x, y);}}public void mouseClicked(MouseEvent e){switch(state){case START:state = RUNNING;break;case GAME_OVER:score = 0;hero = new Hero();enemies = new FlyingObject[0];bullets = new Bullet[0];state = START;break;}}public void mouseExited(MouseEvent e){if(state==RUNNING){state = PAUSE;}}public void mouseEntered(MouseEvent e){if(state==PAUSE){state = RUNNING;}}};this.addMouseListener(l);this.addMouseMotionListener(l);