如何迭代SortedSet来修改其中的项目 [英] How to iterate over a SortedSet to modify items within

问题描述

假设我有一个列表。在for循环中修改list的项目没有问题：

lets say I have an List. There is no problem to modify list's item in for loop:

for (int i = 0; i < list.size(); i++) { list.get(i).setId(i); }

但我有一个SortedSet而不是list。我怎么能用它呢？
谢谢

But I have a SortedSet instead of list. How can I do the same with it? Thank you

推荐答案

首先，设置假设它的元素是不可变的（实际上，可变元素是允许的，但它们必须遵守一个非常具体的合同，我怀疑你的班级会这样做。）

First of all, Set assumes that its elements are immutable (actually, mutable elements are permitted, but they must adhere to a very specific contract, which I doubt your class does).

这意味着通常你不能像使用列表那样就地修改set元素。

This means that generally you can't modify a set element in-place like you're doing with the list.

a <$的两个基本操作c $ c>设置支持是添加和删除元素。修改可以被认为是删除旧元素，然后添加新元素：

The two basic operations that a Set supports are the addition and removal of elements. A modification can be thought of as a removal of the old element followed by the addition of the new one:

1. 你可以照顾通过使用 Iterator.remove（） ;


2. 您可以在单独的容器中累积添加内容并调用< a href =http://docs.oracle.com/javase/6/docs/api/java/util/Set.html#addAll%28java.util.Collection%29 =nofollow> 最后设置.addAll（） 。

1. You can take care of the removals while you're iterating, by using Iterator.remove();
2. You could accumulate the additions in a separate container and call Set.addAll() at the end.

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