This document discusses Service Oriented Architecture and the process of implementing a web service using JAX-WS. It describes how JAX-WS provides standards for both deploying and invoking web services. A service endpoint interface (SEI) maps a WSDL portType to a Java interface that enables invoking the web service. At runtime, JAX-WS dynamically generates a proxy class that implements the SEI using reflection. This allows a client to invoke web service operations by calling methods on the proxy interface.

1. Service Oriented Architecture: 30
JAX WS Client Side Development
Prof Neeraj Bhargava
Vaibhav Khanna
Department of Computer Science
School of Engineering and Systems Sciences
Maharshi Dayanand Saraswati University Ajmer

2. Web Service Architecture

3. General Web Service Model

4. Service Implementation using JAX-WS
• JAX-WS provides the Java Web Services
standard for both deploying and invoking Web
services.
• The Java API for XML Web Services (JAX-WS) is
a Java programming language API for creating
web services, particularly SOAP services.
• JAX-WS is one of the Java XML programming
APIs.
• It's a part of the Java SE and Java EE platforms.

5. Service endpoint interface (SEI)
• JAX-WS provides a standard WSDL to Java
mapping that maps a wsdl:portType to a Java
interface.
• Such an interface is called a service endpoint
interface (SEI) because it is a Java representation
of a Web service endpoint.
• At runtime, JAX-WS can generate an instance of a
SEI that enables the programmer to invoke a Web
service by invoking a method on the SEI.

6. Service endpoint interface (SEI)
• The technology employed by JAX-WS to create a run-time instance
of a SEI is the dynamic proxy class
• This technology enables JAXWS to dynamically create (i.e., to create
at runtime) an instance of a SEI that can be used to invoke a Web
service.
• The internal workings of a JAXWS proxy are based on an instance of
java.lang.reflect.Invocation- Handler that implements a standard
WSDL to Java and Java to WSDL mapping.
• In essence, when you invoke a method on a proxy, the internal
InvocationHandler converts the parameters into a SOAP message
that is sent to the Web service endpoint.
• Likewise, the SOAP response message is converted into an instance
of the SEI return type

7. Web Service Example

8. Client for the web Service Example

9. Invoking a Web service with a Java
proxy

10. Process of creating and using a SEI
• 1. A WSDL to Java mapping tool (e.g., the
GlassFish wsimport utility) is used to read the
target Web service’s WSDL and generate a service
endpoint interface (SEI).
• This step happens prior to compiling and running
the client code that invokes the Web service.
• 2. At runtime, one of the getPort() methods from
the javax.xml- .ws.Service class is used to create a
proxy instance that implements the SEI.

11. Process of creating and using a SEI
• 3. The Web service is invoked simply by invoking
a method from the SEI.
• As indicated in Figure the parameters that get
passed to such a method are instances of JAXB-
generated classes.
• That is because the SEI maps to its corresponding
wsdl:portType using the standard JAXB XML
Schema to Java mapping.
• Each method provided by the SEI corresponds to
a wsdl:operation on the wsdl:portType.

12. Process of creating and using a SEI
• 4. The internals of the proxy instance convert the
SEI method invocation parameters into a SOAP
request and send it to the Web service’s
endpoint.
• In this diagram, the binding is SOAP over HTTP,
but the JAX-WS architecture is designed to
support other bindings.
• 5. Lastly, the proxy instance receives the SOAP
response (or fault) and deserializes it into an
instance of the SEI method’s return type.

13. Assignment
• Discuss the process of implementation of a
Web Service using JAX WS