Container (data structure)
From Wikipedia, the free encyclopedia
In computer science, a container is a class, a data structure, or an abstract data type (ADT) whose instances are collections of other objects. They are used to store objects in an organized way following specific access rules.
The most common examples are: array, list, stack, queue, table, dictionary, tree, graph.
Generally, container classes are expected to implement methods to do the following:
- create a new empty container (constructor),
- report the number of objects it stores (size),
- delete all the objects in the container (clear),
- insert new objects into the container,
- remove objects from it,
- provide access to the stored objects.
There are two types of containers: value containers and reference containers.
Value based containers store copies of the objects. Accessing an object also returns a copy of it. Modifying an external object after it has been inserted in the container will not affect the content of the container.
Reference based containers only store pointers or references to the objects. Accessing an object returns a reference to it. Modifying an external object after it has been inserted in the container could result in modifying the content of the container (or more precisely, the object stored in the container).
Containers are sometimes implemented in conjunction with iterators.
