连续时while循环的冲突（Java）

Question

I build a game that includes moving between worlds. The main class of the program suppose to start by presenting the first world (world1 which is an instance of the firstWorldClass). It should stay in this world until a variable within the class world1 is changing (checked by world1.getMoveWorldIndicator()). Then, it should move to the next world- remove world1, build world2 and add it to the graphic view. Same from world 2 to 3. It works fine when I do it between 2 worlds (delete all the code after add(world2)) or if I leave only the transition between the second and the third worlds. When I put both in a row it stops working (when adding the second while loop). My code:

public class GameManager extends Program implements GameContstants{

public void init() {
    world1=new firstWorldClass();
    add(world1);
    while(!world1.getMoveWorldIndicator()){
        pause(200);
        if(world1.getMoveWorldIndicator())break;
    }
    remove(world1);
    world1=null;
    world2=new secondWorldClass();
    add(world2);
    pause(200);
    while(! world2.getMoveWorldIndicator()){
        pause(200);
        if(world2.getMoveWorldIndicator()) break;
    }
    remove(world2);
    world2=null;
    world3=new thirdWorldClass();
    add(world3);
}   

private firstWorldClass world1;
private secondWorldClass world2;
private thirdWorldClass world3;

}

I suspect that there's some kind of interaction between the while loops or a memory problem but am open to hear any idea/different way to do it.

Thanks!

Answer 1

I think there are lots of factors coming into play here:

• Clean up your code. Keeping a few coding rules is important for bug fixing!
• Don't use repetitive code over and over again. Extract to method or Class
• Keep to class naming conventions => Upper camel case for classes
• Don't set variables to null. Usually compilers will do that for you while optimizing. If you still feel like manually freeing up space or variable names, you should use scope brackets {} around the code instead!
• Breaking down your code, we see lots of redundancies, like "getMoveWorldIndicator()" checks twice per loop, without any different effect from using it only once

I have provided a cleaner - but different - version here, to show you.

But for actually helping you with your code, we really DO NEED more of your code to gain some insight to the problem.

public class GameManager /* extends ... */{

    static class WorldBase {
        public boolean getMoveWorldIndicator() {
            return false;
        }
    }
    static class FirstWorld extends WorldBase {}
    static class SecondWorld extends WorldBase {}
    static class ThirdWorld extends WorldBase {}

    public void init() {
        playWorld(new FirstWorld());
        playWorld(new SecondWorld());
        playWorld(new ThirdWorld());
    }

    private void playWorld(final WorldBase pWorld) {
        add(pWorld);
        while (!pWorld.getMoveWorldIndicator()) {
            pause(200);
        }
        remove(pWorld);
    }

    private void remove(final WorldBase pWorld1) {}
    private void pause(final int pI) {}
    private void add(final WorldBase pWorld1) {}

}