The HTTP Client and WebSocket APIs

This chapter includes 20 problems that are meant to cover the HTTP Client and WebSocket APIs.

Do you remember HttpUrlConnection? Well, JDK 11 comes with the HTTP Client API as a reinvention of HttpUrlConnection. The HTTP Client API is easy to use and supports HTTP/2 (default) and HTTP/1.1. For backward compatibility, the HTTP Client API will automatically downgrade from HTTP/2 to HTTP 1.1 when the server doesn't support HTTP/2. Moreover, the HTTP Client API supports synchronous and asynchronous programming models and relies on streams to transfer data (reactive streams). It also supports the WebSocket protocol, which is used in real-time web applications to provide client-server communication with low message overhead.