Java Collections Framework
Introduction
The Java Collections Framework (JCF) is a set of classes and interfaces that provide a powerful and flexible way to store and manipulate collections of objects.
Java Collections Framework
Table of Contents
- java
- ArrayList
- LinkedList
- Methods
Introduction
The Java Collections Framework (JCF) is a set of classes and interfaces that provide a powerful and flexible way to store and manipulate collections of objects.
java
The java
package is the core of the JCF. It provides the foundation for all the other collection types.
ArrayList
An ArrayList
is a resizable array that implements the List
interface. It is a dynamic data structure that can grow or shrink as needed.
Do You Know?
ArrayList
is backed by an array, so it provides fast random access to elements.
LinkedList
A LinkedList
is a doubly linked list that implements the List
interface. It is a dynamic data structure that allows for efficient insertion and deletion of elements at any position.
Avoid This
Random access in a LinkedList
is slow, as you have to traverse the list from the beginning to reach a particular element.
Methods
The java
package provides a rich set of methods for working with collections. Some of the most commonly used methods include:
add()
: Adds an element to the collection.remove()
: Removes an element from the collection.get()
: Retrieves an element from the collection.size()
: Returns the number of elements in the collection.isEmpty()
: Checks if the collection is empty.
Important Note
The java
package also provides methods for sorting, searching, and iterating over collections.
Summary
- The
java
package provides the foundation for the JCF. ArrayList
is a resizable array that is efficient for random access.LinkedList
is a doubly linked list that is efficient for insertion and deletion.- The
java
package provides a rich set of methods for working with collections.