The emergence of the internet and World Wide Web (WWW) as global media for communication has revolutionized the fields of engineering, e-commerce, and scientific applications. Modern applications, such as the ones related to social media, entertainment, and banking, are no longer strangers to mobile operations carried out through smartphones. Organizations in these domains have been investing a lot into technology to find newer ways of providing services. Gone are the days when we use to make calls to receive services; we now have mobile applications for almost everything, including health, food, banking, and communication. Global organizations obviously chose distributed web applications over legacy/desktop applications, which helped distributed applications evolve; subsequently, communication between such applications became a vital area of concentration.
In this chapter, we will cover the following topics:
- Client-server communication
- Sockets and streams
- Socket programming for Transport Control Protocol (TCP)
- Socket programming for User Datagram Protocol (UDP)
- Multicasting
- Streams
- URLs, URLConnections, and the ContentHandler classes
- URL (base URL and relative URL)
- Practicality of URLs
- ClassLoader