Java构造函数重载歧义

Question

如何解决以下构造函数重载问题？这是一个面试问题，但我很想知道解决方案。

class Player
{
    int nationalRank;
    int internationalRank;
    String name;

    Player(String name, int nationalRank)
    {
        this.name= name;
        this.nationalRank = nationalRank;
        this.internationalRank=0;
    }

    Player(String name, int internationalRank)
    {
        this.name= name;
        this.nationalRank = 0;
        this.internationalRank=internationalRank;
    }
}

这里，编译器将给出错误，因为两个构造函数的参数类型相同。但从逻辑上来说，两者是不同的。如何在不添加任何额外参数的情况下解决这个问题？有没有专门针对这个的设计模式？

Answer 1

class Player
{
    int nationalRank;
    int internationalRank;
    String name;

    private Player(){}

    public static Builder builder() 
    {
       return new Builder();
    }

    public static class Builder
    {
      int nationalRank = -1;
      int internationalRank = -1;
      String name;

      public Builder nationalRank(int nationalRank)
      {
        this.nationalRank = nationalRank;
        return this;
      }

      public Builder internationalRank(int internationalRank)
      {
        this.internationalRank = internationalRank;
        return this;
      }

      public Builder name(String name)
      {
        this.name = name;
        return this;
      }

      public Player build()
      {
        if (nationalRank == -1 && internationalRank = -1)
          throw new IllegalStateException("both ranks haven't been initialized");
        if (null == name)
          throw new IllegalStateException("name hasn't been initialized");
        Player result = new Player();
        result.nationalRank = this.nationalRank;
        result.internationalRank = this.internationalRank;
        result.name = this.name;
        return result;
      }
    }
}

用法:

Player player = Player.builder().name("John").internationalRank(522).build();