Applications for Websocket

The Java EE 7 specification adds new functionality to the Java EE specification. One capability many developers were asking for is support for WebSockets. Real-time bidirectional traffic on the internet is growing. Different actors are involved in this area, including content providers, broadcasters, software developers, and telecom operators. Due to the different characteristics of the involved actors, the success of WebSockets required standardization. The Internet Engineering Task Force (IETF) defined a standard for the WebSocket protocol. This standard defines the low-level protocol that technologies implementing WebSockets should adhere to. For example, it defines how an HTTP connection should be upgraded to a full-duplex bidirectional WebSocket connection. The importance of this standard cannot be underestimated. Different languages and platforms are used to develop applications relying on WebSockets, and they should all rely on the same protocol in order to be interoperable. On top of the WebSocket protocol, a number of technologies and implementations exist facilitating the use of WebSockets in a specific language or platform. For example, the W3C has a working draft describing how to leverage WebSockets from a web page, and ever since Java EE 7, a similar specification has existed for dealing with WebSockets in Java. This specification is defined in JSR 356 and was approved to be part of the Java EE 7 specification. The Java API for WebSocket contains a server API and a client API. Containers that claim to be Java EE 7– compliant implement the server API. The only real difference between a server container and a client container is that a server container provides the infrastructure for registering WebSocket endpoints—it will listen for incoming requests on specific endpoints. The client API is, therefore, a subset of the server API. The Reference Implementation for JSR 356, named Tyrus, is included in GlassFish 4 and contains client modules as well as server modules. The client modules can be used in any Java application and allow developers to connect to any WebSocket endpoint, as long as the endpoint adheres to the IETF 6455 standard. On top of the client modules, the server modules allow applications to register endpoints that will handle all WebSocket communications, as long as the other peer (the client) adheres to the IETF 6455 standard.