A picture that lets you see the Java Collection Class (Summary of Java collection classes)

There are so many articles about the Java Collection Class today, but I recently saw a very interesting picture that basically shows the overall framework of the Java collection. Very intuitive.

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Suppose that the picture is not clearly seen. Click here to see the big picture

Here, the collection classes are divided into two large categories of map and collection.

The four classes (Dictionary, HashTable, vectors, stacks) in the upper-left corner of the picture are thread-safe, but they are all old legacy classes of the JDK. The basic is not how to use today, all have the corresponding substitution class. The map is used to replace the dictionary abstract class in the upper left corner of the image (as stated in the map's official document).

The official recommendation is to use the map interface to replace it. Same for Hashtable. Officially recommended Concurrenthashmap to replace. Then the following vector is an implementation class below the list.

Then the top pink part is the collection class all interface diagram.

The structure of the map is simpler, and the structure of collection is relatively complex. Collection has three inherited interfaces: List, queue, and set.

The next green part is the main implementation class of the collection class.

This is also the collection class that we use most often.

According to the implementation of the interface classification:

Implementations of the map interface are: Enummap, Identityhashmap, HashMap, Linkedhashmap, Weakhashmap, TreeMap

The implementation of the list interface is: ArrayList, LinkedList

The implementation of the set interface is: HashSet, Linkedhashset, TreeSet

Implementations of the queue interface are: Priorityqueue, LinkedList, Arrayqueue

Classification of data structures based on the underlying implementation :

The bottom layer is implemented as an array: Enummap, ArrayList, Arrayqueue
The underlying is implemented as a linked list: Linkedhashset, LinkedList, Linkedhashmap
The bottom layer is implemented in the form of hash table: HashMap, HashSet, Linkedhashmap, Linkedhashset, Weakhashmap, Identityhashmap
The bottom layer is implemented in the form of red and black trees: TreeMap, TreeSet
The bottom layer is implemented in the form of a two-fork heap: priorityqueue

The bottom of the whole block is the class in the Java.util.concurrent package, according to the package name we can know that the class in this package is used to deal with various concurrency scenarios in Java programming.

Next trailer: A more specific interpretation of the intermediate frequently used collection classes (the green part of the frequently used implementation class).

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Original source: http://pierrchen.blogspot.com/2014/03/java-collections-framework-cheat-sheet.html

A picture that lets you see the Java Collection Class (Summary of Java collection classes)