The Java API for XML Web Services (JAX-WS) is a Java programming language API for creating web services. It is part of the Java EE platform from Sun Microsystems. Like the other Java EE APIs, JAX-WS uses annotations, introduced in Java SE 5, to simplify the development and deployment of web service clients and endpoints. It is part of the Java Web Services Development Pack.
The Reference Implementation of JAX-WS is developed as an open source project and is part of project GlassFish, an open source Java EE application server. It is called JAX-WS RI (For Reference Implementation) and is said to be production quality implementation (contrary to the former Reference Implementation being a proof of concept). This Reference Implementation is now part of the Metro distribution[1].
JAX-WS also is one of the foundations of WSIT.
JAX-WS 2.0 replaced the JAX-RPC API in Java Platform, Enterprise Edition 5. The name change reflected the move away from RPC-style and toward document-style web services.