Data Structures
Java Queues
Working with Queues
Java queues use LinkedList or PriorityQueue for FIFO.
Introduction to Java Queues
In Java, queues are used to hold elements prior to processing. They follow the First-In-First-Out (FIFO) order. Java provides several implementations of the Queue interface, with LinkedList and PriorityQueue being the most common.
LinkedList as a Queue
The LinkedList class in Java implements the Queue interface and can be used to create a queue with FIFO behavior. A LinkedList allows for constant-time insertions or removals from the beginning or end.
Here is a simple example demonstrating how to use a LinkedList as a queue:
PriorityQueue in Java
The PriorityQueue class is another implementation of the Queue interface. Unlike a LinkedList, a PriorityQueue does not adhere to the FIFO order. Instead, elements are ordered based on their natural ordering or by a specified comparator.
Below is an example of using a PriorityQueue:
Use Cases for Queues
Queues are widely used in scenarios where tasks need to be processed in order. Common use cases include:
- Task Scheduling: Handling tasks that arrive at different times.
- Data Streaming: Managing streams of data that need to be processed in sequence.
- Print Queue: Managing print jobs at a print server.
