http://localhost:8080/chap03-rest-get-endpoint-servlet-1.0/NewOrders in Java Print ANSI/AIM Code 39 in Java http://localhost:8080/chap03-rest-get-endpoint-servlet-1.0/NewOrders

http://localhost:8080/chap03-rest-get-endpoint-servlet-1.0/NewOrders use jsp barcode 3 of 9 printer todevelop barcode 3 of 9 in java Use Mobile Phone to Scan 1D and 2D Barcodes That pretty much wraps up th jvm Code-39 e how-to discussion for creating and deploying a simple REST Web service using a servlet to invoke a Java method. As you can see, it is not hard to use servlets for deployment of basic RESTful Web services. The three questions posed at the beginning of the section have been answered as follows:.

RESTful Services with and without JWS 1. The Web service implement barcode 3/9 for Java ation class (i.e.

, OrderManager) is instantiated using the no-arg default constructor. This assumes that such a constructor exists and that the class de nition is on the classpath. It also assumes that all resources required by the class are available.

2. The object returned by getNewOrders() is converted into an XML stream using a Transformer. This is a very simple scenario where the method being deployed returns a result that is already represented as an XML infoset.

In most cases, the result will be a Java object that is not an XML infoset representation and requires serialization. 3. The class is deployed by bundling it with a dedicated servlet.

Problems are encountered, however, when you want to deploy multiple services. Using the architecture described in this section, you need to have a servlet for each Web service. That quickly becomes cumbersome and inef cient.

What is needed is an invocation subsystem so that a single servlet can be used to invoke more than one service. However, to do that requires a method of mapping URLs to services at a ner granularity than provided by the web.xml le.

As you can see in Example 3 15, the web.xml mapping is from a single URL to a single servlet. So, for a single servlet to handle multiple URLs (and multiple Web services), additional deployment meta-data must be added to this simple architecture that falls outside of the servlet processing model.

One way to do this might be to map all base URLs of the form* to the servlet. Then, local paths such as /getNewOrder, /addCustomerHistory, and so on are mapped to individual Web services.

In fact, this approach is used by a variety of Web Services engines, including Apache Axis [AXIS] and the SOA-J engine introduced in 11. JWS also offers a variation on this approach, which I examine in detail in 7. For now, I m going to defer further discussion of deployment issues and move on to the nuts and bolts of how to deploy this New Orders example Web service using JAX-WS and JSR-181 annotations.

. 3.5.2 Deploying a RESTful Service with JWS This section illustrates how jar Code 39 Full ASCII a Web service is deployed using JWS. This is the same service that was deployed in Section 3.5.

1. However, the operation of the service as deployed using JWS is very different. The primary difference here is that instead of using a servlet as in Example 3 14, the JWS version uses an instance of Provider<Source> to implement the RESTful service.

Example 3 16 shows how it is implemented. The @WebServiceProvider annotation used in this example is de ned by the JAX-WS 2.0 speci cation.

It is used to declare a reference. Basic SOA Using REST to a Web Service that implem Java USS Code 39 ents a Provider<Source> interface. The @WebServiceProvider annotation is required for deploying a RESTful Web service and is discussed in more detail in 7, which covers JAX-WS server-side development and deployment. The Provider<Source> interface is basically the server-side version of Dispatch<Source> discussed in Section 3.

3.2. It enables you to create a Web service that works directly with the XML message as an instance of javax.

xml.transform.Source rather than a JAXB 2.

0 representation of the XML message. Along with @WebServiceProvider, the javax.xml.

ws.Provider interface is explained in greater detail in 7. In this section, my goal is just to give you a quick example of how a RESTful service can be created and deployed with JAX-WS.

The @BindingType annotation (

BindingType) used in Example 3 16 is also de ned by the JAX-WS 2.0 speci cation and is used to specify the binding that should be employed when publishing an endpoint. The property value indicates the actual binding.

In this case, you can see that the value is speci ed as follow:.
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