废话开篇
由于项目需要，需要对Java Collections进行系统地了解，所以在此记录下，方便自己，服务他人。
Java Collections 简介
Java Collections 框架主要包含interfaces, implementations, aggregate operations and algorithms四个部分，后续的文章也是从这四部分来分别介绍。
Java Collections定义
中文的百度上有，自己麻烦参考下吧，这里贴出官方定义：
A collections framework is a unified architecture for representing and manipulating collections. All collections frameworks contain the following:
- Interfaces: These are abstract data types that represent collections. Interfaces allow collections to be manipulated independently of the details of their representation. In object-oriented languages, interfaces generally form a hierarchy.
- Implementations: These are the concrete implementations of the collection interfaces. In essence, they are reusable data structures.
- Algorithms: These are the methods that perform useful computations, such as searching and sorting, on objects that implement collection interfaces. The algorithms are said to be polymorphic: that is, the same method can be used on many different implementations of the appropriate collection interface. In essence, algorithms are reusable functionality.
废话收尾
有好多文章都说Java Collections Framework这么好那么好，其实我觉得就两点好：一是减少我们这些码农的敲击键盘的次数；二是以后的人能看懂咱们这些前人写的code。