如何訪問另一個類的數組

Question

我想操作在main方法中聲明的名爲「players」的數組。我想在我的課堂中使用名爲「Glucksspielthread」的「玩家」 我知道我不能訪問「玩家」，因爲它是在主要方法中聲明的，並且對於其他類是不可見的。

我該如何解決這個問題？這裏是我的代碼：

import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 

public class Glucksspieltest { 
    public static void main(String[] args) { 
     int numPlayers = Integer.parseInt(args[0]); 
     int threadSize = Integer.parseInt(args[1]); 

     ExecutorService es = Executors.newFixedThreadPool(threadSize); 
     Glucksspielthread[] players = new Glucksspielthread[numPlayers]; 
     for (int i = 0; i < numPlayers; i++) { 
      players[i] = new Glucksspielthread(i); 
      es.execute(players[i]); 
     } 
    } 
} 

class Thinker { 
    public static void think(int Millisekunden) { 
     try { 
      Thread.sleep(Millisekunden); 
     } catch (InterruptedException e) { 
      e.printStackTrace(); 
     } 
    } 

    public static void randomThink(int minMillisekunden, int  maxMillisekunden) { 
     System.out.println("test"); 
    } 
} 

class Glucksspielthread implements Runnable { 
    public int playerNumber; 

    Glucksspielthread(int number) { 
      playerNumber = number; 
    } 

    @Override 
    public void run() { 
     for (int i = 0; i <= playerNumber; i++) { 
      // here, I want to operate on array called "players" that is declared in the main method 
     } 
    } 
} 

Answer 1

只是爲了測試目的，讓你的球員靜態變量和公衆在Glucksspieltest類，像這樣：

public class Glucksspieltest { 

public static Glucksspielthread[] players; 

然後存取權限是在這樣的Glucksspielthread類：

for (int i = 0; i <= playerNumber; i++) { 
     // here, I want to operate on array called "players" that is declared in the main method 
     Glucksspieltest.players 
    } 

Answer 2

添加方法Glucksspieltest類，並讓玩家陣列全球：

public class Glucksspieltest { 
    private static Glucksspielthread[] players; 

    public static Glucksspielthread[] getPlayers(){ 
     return players; 
    } 

    public static void main(String[] args) { 
     int numPlayers = Integer.parseInt(args[0]); 
     int threadSize = Integer.parseInt(args[1]); 

     ExecutorService es = Executors.newFixedThreadPool(threadSize); 
     players = new Glucksspielthread[numPlayers]; 
     for (int i = 0; i < numPlayers; i++) { 
      players[i] = new Glucksspielthread(i); 
      es.execute(players[i]); 
     } 
    } 
} 

這樣你就可以通過調用getPlayers()方法來獲得數組。

（需要注意的是，它會被勸添加一個構造函數來初始化並填寫players陣列，並從main方法分離機管理爲好。）

Answer 3

讓玩傢俬有全球全球化志願服務青年變量

public class Glucksspieltest { 
//Make a Global reference variable players 
    private static Glucksspielthread[] players; 

// Make a getter Method to get players 
public static Glucksspielthread[] getPlayers(){ 
    return players; 
} 

    public static void main(String[] args) { 
     int numPlayers = Integer.parseInt(args[0]); 
     int threadSize = Integer.parseInt(args[1]); 

     ExecutorService es = Executors.newFixedThreadPool(threadSize); 

     players = new Glucksspielthread[numPlayers]; 
     for (int i = 0; i < numPlayers; i++) { 
      players[i] = new Glucksspielthread(i); 
      es.execute(players[i]); 
     } 
    } 
} 

並通過Glucksspieltest.getPlayers（）訪問它;

class Glucksspielthread implements Runnable { 
    public int playerNumber; 

    private static Glucksspielthread[] players; 

    Glucksspielthread(int number) { 
      playerNumber = number; 
    } 

    @Override 
    public void run() { 
     for (int i = 0; i <= playerNumber; i++) { 
      // here, I want to operate on array called "players" that is declared in the main method 
     players= Glucksspieltest.getPlayers(); // play with players 
     } 
    } 
}