匹配兩個列表值，最後得到一個具有不同值的最終列表

Question

我在這裏有問題。我有兩個列表，這兩個列表都有一些共同的元素。 這些常見元素以及值必須放在另一個列表中。這是非常煩人的要求。

我的測試類如下：

import java.util.ArrayList; 
    import java.util.List; 

public class Player { 
    private int singleModeVal; 
    private int doubleModeVal; 
    private String mode; 
    private String name; 
    public Player(){} 

    public String getName(){ 
     return name; 
    } 
    public void setName(String name){ 
     this.name = name; 
    } 
    public int getSingleModeVal(){ 
     return singleModeVal; 

    } 
    public void setSingleModeVal(int val1){ 
     this.singleModeVal=val1; 
    } 
    public int getDoubleModeVal(){ 
     return doubleModeVal; 
    } 
    public void setDoubleModeVal(int val2){ 
     this.doubleModeVal=val2; 
    } 
    public String getMode(){ 
     return mode; 
    } 
    public void setMode(String mode){ 
     this.mode = mode; 
    } 
    public List<Player> getSinglePlayerscoreList(){ 
     List<Player> singlePlayerscoreList = new ArrayList<Player>(); 
     for(int i=0;i<2;i++){ 
      Player player = new Player(); 
      player.setName("A"); 
      player.setMode("singlePlayerMode"); 
      player.setSingleModeVal(100); 
      player.setDoubleModeVal(200); 
      singlePlayerscoreList.add(player); 
     } 
     return singlePlayerscoreList; 
    } 
    public List<Player> getDoublePlayerscoreList(){ 
     List<Player> doublePlayerscoreList = new ArrayList<Player>(); 
     for(int i=0;i<2;i++){ 
      Player player = new Player(); 
      player.setName("B"); 
      player.setMode("doublePlayerMode"); 
      player.setSingleModeVal(300); 
      player.setDoubleModeVal(400); 
      doublePlayerscoreList.add(player); 
     } 
     return doublePlayerscoreList; 
    } 
} 

另一類是：

import java.util.ArrayList; 
import java.util.Iterator; 
import java.util.List; 

public class Tester { 
    private Player player = new Player(); 

    public static void main(String args[]){ 
     new Tester().showValue(); 
    } 

    private void showValue(){ 
     List<Player> singlePlayerScore = new ArrayList<Player>(); 
     List<Player> doublePlayerScore = new ArrayList<Player>(); 
     singlePlayerScore = player.getSinglePlayerscoreList(); 
     doublePlayerScore = player.getDoublePlayerscoreList(); 
     List<Player> allScoreList = new ArrayList<Player>(); 
     allScoreList.addAll(singlePlayerScore); 
     allScoreList.addAll(doublePlayerScore); 
      How do i iterate here, and print my data as: 


Name   singlePlayerScore Double Player Score TotalScore  
A    100     200    300  
B    300     400    700 


    } 
    } 

} 

當我重複我收到了兩次，它的價值和B相同。

有沒有一種有效的方法來執行所需的。

Answer 1

有一種名爲retainAll()的方法，它完全相反。

所以，你可以做到以下幾點：

// create copies of source list because retainAll() works in place 
List<T> copy1 = new ArrayList<T>(one); 
List<T> copy2 = new ArrayList<T>(two); 
copy1.retainAll(two); 
copy2.retainAll(one); 
// now copy1 and copy2 contain common elements 

// create collection of retained elements 
List<T> retained = new ArrayList<T>(); 
retained.addAll(copy1); 
retained.addAll(copy2); 

// refresh content of copy1 and copy2 (it is abuse but ok for the example) 
copy1 = new ArrayList<T>(one); 
copy2 = new ArrayList<T>(two); 
// remove all retained elements, so now both collection contain elements unique for these collections only 
copy1.removeAll(retained); 
copy2.removeAll(retained); 

// create collection that contains all distinct elements. 
List<T> distinct = new ArrayList<T>(); 

distinct.addAll(copy1); 
distinct.addAll(copy2);