如何迭代對象數組並調用對象的方法？

Question

這是我的代碼。如果可能的話，我希望它不那麼笨拙。足球和籃球是玩家的子類。 arr [i] .methodName（）僅適用於超類中的方法，如果可能，我希望以相同的方式調用子類中的方法。

import java.util.Arrays; 
    public class PlayerClient { 
     public static void main(String[] args) { 
      Soccer s1 = new Soccer("Robert", 12, 200000, 3, 1, 17); 
      Soccer s2 = new Soccer("Carrot", 7, 400000, 1, 4, 35); 
      Basketball b1 = new Basketball("Jeremy", 37, 300000, 70, 6.3); 
      Basketball b2 = new Basketball("Lebron", 65, 1000000, 130, 9.0); 
      Player[] arr = {s1, s2, b1, b2}; 
      for (int i = 0; i < arr.length; i++) { 
       System.out.println("\n\n" + arr[i].getName()); 
       System.out.println(arr[i].getNumber()); 
       System.out.println(arr[i].getSalary()); 
       if (arr[i].equals(s1)) { 
        System.out.println(s1.getYellowFlags()); 
        System.out.println(s1.getRedFlags()); 
        System.out.println(s1.getGoalsScored() + "\n\n"); 
       } else if (arr[i].equals(s2)) { 
        System.out.println(s2.getYellowFlags()); 
        System.out.println(s2.getRedFlags()); 
        System.out.println(s2.getGoalsScored() + "\n\n"); 
       } else if (arr[i].equals(b1)) { 
        System.out.println(b1.getjumpHeight()); 
        System.out.println(b1.getjumpHeight() + "\n\n"); 
       } else if (arr[i].equals(b2)) { 
        System.out.println(b2.getjumpHeight()); 
        System.out.println(b2.getBasketsScored() + "\n\n"); 
       } 
      } 
     } 
    } 

Answer 1

我想你正在尋找的是模板方法設計模式：

https://www.tutorialspoint.com/design_pattern/template_pattern.htm

定義的基類的抽象方法，強制它們在子類中實現的。然後你可以調用基類型的方法，而每個子類可能有不同的實現。

import java.util.Arrays; 
public class PlayerClient { 
    public static void main(String[] args) { 
     Soccer s1 = new Soccer("Robert", 12, 200000, 3, 1, 17); 
     Soccer s2 = new Soccer("Carrot", 7, 400000, 1, 4, 35); 
     Basketball b1 = new Basketball("Jeremy", 37, 300000, 70, 6.3); 
     Basketball b2 = new Basketball("Lebron", 65, 1000000, 130, 9.0); 
     Player[] arr = {s1, s2, b1, b2}; 
     for (int i = 0; i < arr.length; i++) { 
      System.out.println("\n\n" + arr[i].getName()); 
      System.out.println(arr[i].getNumber()); 
      System.out.println(arr[i].getSalary()); 
      System.out.println(arr[i].printScore()); 
     } 
    } 
} 


public abstract class Player { 
    abstract void printScore(); 

    // existing code 
} 

public class Soccer extends Player { 
    @Override   
    void printScore() { 
     System.out.println(getYellowFlags()); 
     System.out.println(getRedFlags()); 
     System.out.println(getGoalsScored() + "\n\n"); 
    } 

    // existing methods 
} 

public class Basketball extends Player { 
    @Override   
    void printScore() { 
     System.out.println(getjumpHeight()); 
     System.out.println(getjumpHeight() + "\n\n"); 
    } 

    // existing methods 
}