Question

最深的元素：

class Player {
    //fields contain:
    int value;
}

收集于：

class Team {
    //fields contain:
    ArrayList<Player> players;
}

收集于：

class Splitter {
    //fields contain:
    Teams[] teams;
}

在Splitter的函数中，我必须克隆teams。我基本上必须通过克隆每个teams对象来克隆数组Team，每个对象都包含一个我必须克隆的ArrayList players。我不想要自己克隆播放器对象。

到目前为止我的解决方案看起来像这样：

private Team[] deepClone(Team[] teams) {
    Team[] new_teams = new Team[teams.length];
    for (int i = 0; i < teams.length; i++) {
        new_teams[i] = new Team();
        for (Player player : teams[i].getPlayers())
            new_teams[i].getPlayers().add(player);
    }
    return new_teams;
}

我可以改变什么来使这更有效或更优雅？

Answer 1

您当前的解决方案相当于这种更简单的形式：

private Team[] deepClone(Team[] teams) {
    Team[] new_teams = new Team[teams.length];
    for (int i = 0; i < teams.length; i++) {
        new_teams[i] = new Team();
        new_teams[i].getPlayers().addAll(teams[i].getPlayers());
    }
    return new_teams;
}

如果没有使用stream和lambdas的循环索引，你可以使它更优雅：

private Team[] deepClone(Team[] teams) {
    return Stream.of(teams).map(team -> {
        Team newTeam = new Team();
        return newTeam.getPlayers().addAll(team.getPlayers());
    }).toArray(Team[]::new);
}

Answer 2

理想情况下，如果你想进行完美的深度克隆，你也应该克隆玩家，我们应该总是在每个类中编写克隆方法，然后调用克隆方法来克隆，无论如何你可以进入下面。

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2 个答案: