java - 在初始化之外的Java中创建对象

因此对于我正在创建的游戏，我有一些扩展GameDriver的类。

到目前为止，在所有其他类上，我都可以扩展GameDriver，然后在GameDriver中可以执行以下操作:

ArrayList<Card>  library = new ArrayList<Card>();

今天，我开始学习GameAI类，并扩展了GameDriver，当我提出以下内容时:

GameAI Enemy = new GameAI();

在同一位置，我放置了另一行代码(在公共类GameDriver的正下方)

我得到:

java.lang.StackOverflowError
at java.util.WeakHashMap.expungeStaleEntries(Unknown Source)
at java.util.WeakHashMap.getTable(Unknown Source)
at java.util.WeakHashMap.get(Unknown Source)
at java.awt.Component.checkCoalescing(Unknown Source)
at java.awt.Component.<init>(Unknown Source)
at java.awt.Container.<init>(Unknown Source)
at java.awt.Panel.<init>(Unknown Source)
at java.awt.Panel.<init>(Unknown Source)
at java.applet.Applet.<init>(Unknown Source)
at GameDriver.<init>(GameDriver.java:14)
at GameAI.<init>(GameAI.java:8)
at GameDriver.<init>(GameDriver.java:40)
at GameAI.<init>(GameAI.java:8)

如果我将其放在applet的public void init()中，那么它不会在运行时产生错误，但是我将无法从其他方法访问它，我是否在寻找一些东西？通常所有的夜宵都不能帮助我的大脑...

截至目前，GameAI的外观如下:

public class GameAI extends GameDriver {

    public int life;
    public int energy;

    public void drawPhase(){

    }

    public GameAI(){
        life = 20;
        energy = 2;
    }
}

然后是GameDriver的一些内容:

public class GameDriver extends Applet implements MouseMotionListener,MouseListener {

Graphics g;
Image offscreen;
Dimension dim;

int playerLife = 20;
int playerEnergy = 8;

int xMouse;
int yMouse;
int lineThickness = 4;
int handSize = 6;
int currentHover;
boolean slotHover;
int currentSelected;
boolean slotClicked;
int currentHoverBoard;
boolean slotHoverBoard;
boolean slotClickedBoard;
int currentSelectedBoard;

boolean canPlace;
ArrayList<Card>  library = new ArrayList<Card>();
ArrayList<Card>  hand = new ArrayList<Card>();
ArrayList<Card>  playerBoard = new ArrayList<Card>();
GameAI Enemy;
int[] handBoxX = new int[handSize];
int[] handBoxY = new int[handSize];
int[] handBoxW = new int[handSize];
int[] handBoxH = new int[handSize];

int[] playerBoardX = new int[8];
int[] playerBoardY = new int[8];
int[] playerBoardW = new int[8];
int[] playerBoardH = new int[8];



public void init(){
    this.setSize(640, 480);
    dim = this.getSize();
    addMouseMotionListener(this);
    addMouseListener(this);
    createLibrary();
    drawFirstHand();
    printHand();


    GameAI Enemy = new GameAI();
    checkEnemy();



    offscreen = createImage(this.getSize().width,this.getSize().height);
    g = offscreen.getGraphics();
}

public void checkEnemy(){
    System.out.println(Enemy.energy);
}

... Alot more methods and stuff below, but nothing to do with the GameAI enemy

最佳答案

您正在GameDriver(它扩展的类)内部创建GameAI对象。这将导致递归继续，直到您用尽内存。

解决方案:不要这样做。您的GameAI类不应扩展GameDriver，因为这是共享信息的错误方法，即使您没有这种递归噩梦，它也根本无法工作。而是给GameAI一个GameDriver字段，并将GameDriver实例通过其构造函数传递给GameAI。

即

class GameAI {
   private GameDriver gameDriver;

   public GameAI(GameDriver gameDriver) {
      this.gameDriver = gameDriver;
   }

   //.... more code
}

编辑2
如果您想要一个GameAI对象，则可以

GameAI gameAi = new GameAI(this);

如果需要数组或列表，则可以循环执行。