Question

我正在尝试为派对创建模拟。将有4个班级：主持人，工程师，艺术家和科学家。其中每一个都必须放置在50x50的场地上。为了做到这一点，我必须创建一个随机发生器，因为我之前从未做过随机发生器，所以我真的坚持了这个部分很长时间，所以我希望能得到一些帮助。（我是初学者，是的。）我目前收到此错误：“线程中的异常”主“java.lang.NullPointerException 在Simulator.populate（Simulator.java:88）在Simulator.partyStatus（Simulator.java:101）在Simulator。（Simulator.java:56）在Simulator.main（Simulator.java:41）建立成功（总时间：3秒）“

如果有不同的，更好的方法，那么我会非常乐意看到它，如果你需要更多关于此的细节，那就问一下。

提前致谢！

public class Simulator {

    private static double ARTIST_CREATION_PROBABILITY = 0.2;
    private static double HOST_CREATION_PROBABILITY = 0.2;
    private static double ENGINEER_CREATION_PROBABILITY = 0.2;
    private static double SCIENTIST_CREATION_PROBABILITY = 0.2;

    private static int seed;

    private ArrayList<Artist> artists;
    private ArrayList<Scientist> scientists;
    private ArrayList<Engineer> engineers;
    private ArrayList<Host> hosts;
    private ArrayList<People> people;

    private int depth;
    private int width;
    private Field field;
//    private static int step;
    private SimulatorView simView;

    Random rand = RandomGenerator.getRandom();


    public static void main(String [] args) {
//     SimulatorView simView = new SimulatorView(50,50); 
     Simulator simulator = new Simulator(50,50);


    }

    /**
     *
     * @param depth
     * @param width
     */
    public Simulator(int depth, int width) {
        this.simView = new SimulatorView(depth, width);
        this.field = new Field(depth, width);
        this.depth = depth;
        this.width = width;
        this.partyStatus(simView, field);

        RandomGenerator.initialiseWithSeed(seed);
    }   

    public void populate(Field field){
//        People host = new Host();
//        People artist = new Artist();
//        People scientist = new Scientist();
//        People engineer = new Engineer(); 
//        field.place(artist, 10, 10);
//        field.place(scientist, 20, 20);
//        field.place(engineer, 30, 30);
//        field.place(host,40,40);

               Random rand = RandomGenerator.getRandom();
        field.clear();

         for(int row = 0; row<field.getDepth(); row++){
            for(int col = 0; col<field.getWidth(); col++){
               if(rand.nextDouble() < ARTIST_CREATION_PROBABILITY){
                 Artist artist = new Artist();
                 artists.add(artist);
                 field.place(artist, row, col);
               }
               else if(rand.nextDouble() < SCIENTIST_CREATION_PROBABILITY){
                 Scientist scientist = new Scientist();
                 scientists.add(scientist);
                 field.place(scientist, row, col);
               }
               else if(rand.nextDouble() < ENGINEER_CREATION_PROBABILITY){
                 Engineer engineer = new Engineer(); 
                 engineers.add(engineer);
                 field.place(engineer, row, col);
               }
               else if(rand.nextDouble() < HOST_CREATION_PROBABILITY){
                 Host host = new Host();
                 hosts.add(host);
                 field.place(host, row, col);
               } 
            }
         }        
    }

    public void partyStatus(SimulatorView simView, Field field){
        this.populate(field);
        simView.setColor(Artist.class, Color.ORANGE);
        simView.setColor(Scientist.class, Color.BLUE);
        simView.setColor(Engineer.class, Color.MAGENTA);
        simView.setColor(Host.class, Color.GREEN);
        simView.showStatus(1, field);
    }  
    }

派对模拟和随机发生器

0 个答案: