Shulou(Shulou.com)06/02 Report--

Today, I will talk to you about the role of the addAll () method in List, which may not be well understood by many people. In order to make you understand better, the editor has summarized the following content for you. I hope you can get something according to this article.

AddAll (Collection c)

This method adds all elements in the collection to the end of the list in the order returned by the iterator of the specified collection. If the specified collection is modified while this operation is in progress, the behavior of this operation is uncertain. This means that if the specified collection is this list and the list is not empty, then the behavior of this call is indeterminate.

The name description c contains the collectionreturn of the elements to be added to this list. If the list is changed due to the call, trueThrowsNullPointerException is returned: if the specified collection is null

Note:

Collection throws a null pointer exception if it is NULL

If the element in collection is empty, the pointer will not be emptied.

After reading the above, do you have any further understanding of the function of the addAll () method in List? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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