Java Solar System Small game analysis and source code

Java Solar System Small game analysis and source code

-20150809

Recently looked at some object-oriented knowledge. Then follow the teacher's commentary made a solar system of the planets around the sun to the game, to practice consolidating the knowledge of recent studies:

Knowledge points: Inheritance of classes, overloading and rewriting of methods, polymorphism, encapsulation, etc.

Analysis:

1. Need to load pictures, drawings

2. Build a panel. Main Page

3. Planetary class

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Let's take a look at the source code structure diagram:

Now analyze the functions of each class progressively:

1) Tool class-----Util package

The--constant class encapsulates the constants used in the game

The--gameutil class encapsulates the game's picture loading function

The--myframe class encapsulates the construction of the game panel. Parent class for each panel

------did so. The purpose is to encapsulate the data. Facilitates the expansion of programs

Constant.java

Package Util;public class Constant {public static final int game_width = 800;public static final int game_height = 600;}

Gameutil.java

Package Util;import Java.awt.image;import Java.awt.image.bufferedimage;import java.io.ioexception;import Java.net.url;import javax.imageio.imageio;/** * Tool class (load picture) * @author long * */public class Gameutil {private Gameutil () {}< The c2/>//tool class will typically construct a method private public static Image GetImage (String path) {URL u = GameUtil.class.getClassLoader (). GetResource (Path) ; BufferedImage img = null;try {img = imageio.read (u);} catch (IOException e) {e.printstacktrace ();} return img;}}

Myframe.java

Package Util;import javax.swing.jframe;import javax.swing.jpanel;/** * Game Panel Parent class * @author long * */public class MyFrame Ext Ends jpanel{/** * Method of loading frame */public void Launchframe () {JFrame frame = new JFrame ("Mygame"); Frame.add (this); Frame.setsize (constant.game_width,constant.game_height); Frame.setalwaysontop (true); Set its total at the top frame.setlocationrelativeto (null); Set window initial position frame.setdefaultcloseoperation (jframe.exit_on_close); frame.setvisible (true); new Paintthread (). Start () ;} /** * Defines a thread class for redrawing a window.  is an inner class * @author Dell * */class Paintthread extends Thread {public void run () {while (true) {repaint (); try {Thread.Sleep (40); 1s = 1000ms} catch (Interruptedexception e) {e.printstacktrace ();}}}   public static void Main (string[] args) {new MyFrame (). Launchframe ();}}

2) Basic event handling Class---solar bag

--planet class of planets inherit to star class

--solarframe class game main panel class inherits to MyFrame class

--star Planet Class, the parent of each planet

--test class Test class. No need to explain

Planet.java

Package Solar;import java.awt.color;import java.awt.graphics;import java.awt.image;import util. gameutil;/** * Planetary class, inheriting to Star class * @author long * */public class Planet extends star{//In addition to pictures, coordinates, the planets are executed along the ellipse: Long axis, short axis, movement speed, rotation angle.
Executes a double longaxis around a star;  Oval long axis double Shortaxis;      Elliptic short axis double speed;     Flight speed double degree;       Rotation Angle Star Center; Round Planet public void Draw (Graphics g) {//g.drawimage (img, (int) x, (int) y, null); Super.draw (g);d rawtrace (g); move (); public void Drawtrace (Graphics g) {Double Tracex,tracey,tracewidth,traceheight;tracex = (CENTER.X+CENTER.W/2)- Longaxis;tracey = (CENTER.Y+CENTER.H/2)-shortaxis;tracewidth = 2*longaxis;traceheight = 2*shortAxis; Color C = G.getcolor (); G.setcolor (Color.Blue); G.drawoval ((int) Tracex, (int) TraceY, (int) tracewidth, (int) traceheight ); G.setcolor (c);}  public void Move () {//Fly along elliptical trajectory x = center.x + Longaxis * Math.Cos (degree); y = center.y + Shortaxis * Math.sin (degree);d Egree + = speed;} Public Planet (Image img,double x,double y) {super (img,x,y);} Public Planet (String imgpath,double x,double y) {super (imgpath,x,y);} Public Planet (Star center,image img,double longaxis, double shortaxis,double speed) {super (); this.x = (center.x+center. W/2) + Longaxis;this.y = (center.y+cENTER.H/2) + shortaxis;this.img = Img;this.longaxis = Longaxis;this.shortaxis = Shortaxis;this.speed = Speed;this.center = center;} Public Planet (Star center,string imgpath,double longaxis, double shortaxis,double speed) {This (center,gameutil.getimag E (Imgpath), longaxis,shortaxis,speed);}}

Solarframe.java

Package Solar;import java.awt.graphics;import java.awt.image;import util. Constant;import util. Gameutil;import util. Myframe;public class Solarframe extends myframe{int width = constant.game_width/2;int height = constant.game_height/2;i Mage Bg=gameutil.getimage ("Images/bg.png"); Star Sun = new Star ("Images/sun.jpg", width,height); Planet earth = new Planet (Sun, "images/earth.png", 100,60,0.1); Planet mars = new Planet (Sun, "images/mars.png", 180,100,0.15), @Overridepublic void Paint (Graphics g) {g.drawimage (bg, 0, 0, NULL); Sun.draw (g); Earth.draw (g); Mars.draw (g);} public static void Main (string[] args) {new Solarframe (). Launchframe ();}}

Star.java

Package Solar;import java.awt.graphics;import java.awt.image;import util. Gameutil;public class Star {public Image img;public double x,y;int w,h;public void Draw (Graphics g) {G.drawimage (img, (int) x, (int) y, null);} Public Star () {}public star (Image img) {this.img = IMG;THIS.W = Img.getwidth (null); this.h = Img.getheight (null);} Public Star (Image img,double x,double y) {this (IMG); this.x = X;this.y = y;} Public Star (String imgpath,double x,double y) {This (Gameutil.getimage (Imgpath), x, y);}}

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Summary: The small game on the package of code to deal with better, easy to expand the program. Embodies the powerful object-oriented, different functions encapsulated in different classes and methods. The common part of the class is encapsulated in the parent class, which improves the reusability of the code. There will be a variety of small problems and details in the early stages of writing, but after processing these, it is easier to expand the number of planets at a later stage, and a new planetary object and then a panel can be painted. Object-oriented water is too deep, this is only a preliminary small, still need to continue efforts to research.!!

Java Solar System Small game analysis and source code