arraylist sublist的易错用法-优快云博客

本文详细解析了Java中List接口的subList()方法，该方法返回从fromIndex（包含）到toIndex（不包含）的指定部分的视图。文章强调了toIndex参数的特性，即它并不包含在子列表中，并提供了使用示例。

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注意:toIndex - high endpoint (exclusive) of the subList

就是说 toIndex是不取值的.

Exp:modelList.subList(0, + 200)

取的是modelList的第0--199条共200个数据,第200是不取的.

截取部分官网说明,注意标红部分:

https://docs.oracle.com/javase/7/docs/api/java/util/ArrayList.html#subList(int,%20int)

public List<E> subList(int fromIndex,

int toIndex)

Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive. (If fromIndex and toIndex are equal, the returned list is empty.) The returned list is backed by this list, so non-structural changes in the returned list are reflected in this list, and vice-versa. The returned list supports all of the optional list operations.

This method eliminates the need for explicit range operations (of the sort that commonly exist for arrays). Any operation that expects a list can be used as a range operation by passing a subList view instead of a whole list. For example, the following idiom removes a range of elements from a list:

list.subList(from, to).clear();

Similar idioms may be constructed for indexOf(Object) and lastIndexOf(Object), and all of the algorithms in the Collections class can be applied to a subList.

The semantics of the list returned by this method become undefined if the backing list (i.e., this list) is structurally modified in any way other than via the returned list. (Structural modifications are those that change the size of this list, or otherwise perturb it in such a fashion that iterations in progress may yield incorrect results.)

Specified by:

subList in interface List<E>

Overrides:

subList in class AbstractList<E>

Parameters:

fromIndex - low endpoint (inclusive) of the subList

toIndex - high endpoint (exclusive) of the subList

Returns:

a view of the specified range within this list

Throws:

IndexOutOfBoundsException - if an endpoint index value is out of range (fromIndex < 0 || toIndex > size)

IllegalArgumentException - if the endpoint indices are out of order (fromIndex > toIndex)