獲取ArrayIndexOutOfBoundsException，數組大小是動態確定的

Question

在下面的代碼中，我得到ArrayIndexOutOfBoundsException。我對Java不熟悉的線索並沒有讓它超出界限。我調試這個代碼，輸入4個條目後終止。

 String[] suit = {"Clubs", "Diamonds", "Hearts", "Spades"}; 
     String[] rank = {"2", "3", "4", "5", "6", "7", "8", "9", "10", "Jack", "Queen", "King", "Ace"}; 
     String[] deck = new String[suit.length * rank.length]; 

     int i = (int)(Math.random()*rank.length); 
     int j = (int)(Math.random()*suit.length); 

     System.out.println(rank[i]+" of "+suit[j]);   

     for(int k=0; k<suit.length; k++){ 
      for(int l=0; l<rank.length; l++){ 
       //on the following line. 
       deck[rank.length*k + l] = rank[k]+ " of "+suit[l]; 
      } 
     } 

     for(String s : deck){ 
      System.out.println(s); 
     } 

Answer 1

我敢肯定你有這些變量混合起來

deck[rank.length*k + l] = rank[k]+ " of "+suit[l]; 

應該

deck[rank.length*k + l] = rank[l]+ " of "+suit[k]; 

Answer 2

問題的原因是你應該使用k指數，而不是l：

deck[rank.length*k + l] = rank[k]+ " of "+suit[l]; 

像這樣：

deck[rank.length*k + l] = rank[k]+ " of "+suit[k]; 

因爲rank.length>suit.length對於有西裝數組中此指數suit[4]沒有數據。