考虑以下示例：List<String> people = getPeople().stream() .collect(collectingAndThen(toList(), Collections::unmodifiableList));对于这个例子，我使用的是Collections::unmodifiableList方法，所以让我们检查源代码：/** * Returns an unmodifiable view of the specified list. This method allows * modules to provide users with "read-only" access to internal * lists. Query operations on the returned list "read through" to the * specified list, and attempts to modify the returned list, whether * direct or via its iterator, result in an * <tt>UnsupportedOperationException</tt>.<p> * * The returned list will be serializable if the specified list * is serializable. Similarly, the returned list will implement * {@link RandomAccess} if the specified list does. * * @param list the list for which an unmodifiable view is to be returned. * @return an unmodifiable view of the specified list. */public static <T> List<T> unmodifiableList(List<? extends T> list) { return (list instanceof RandomAccess ? new UnmodifiableRandomAccessList<>(list) : new UnmodifiableList<>(list));}正如@Pshemo 在评论中提到的那样，它UnmodifiableList可以作为列表的包装器，您还可以在源代码中检查该类包含一个列表： static class UnmodifiableList<E> extends UnmodifiableCollection<E> implements List<E> { private static final long serialVersionUID = -283967356065247728L; final List<? extends E> list; // Here is the wrapped list UnmodifiableList(List<? extends E> list) { super(list); this.list = list; } ...}可以在此处找到用于提取这些代码的源代码。所以回答你的问题：流使用方法等Collections::unmodifiableList方法创建不可变列表内部流不会在不同的列表中添加任何内容，因为它ImmutableList只是作为包装器工作Collection您还可以查看文档和来源，以了解这些不可变相关方法和对象的工作原理。