1. 课堂讨论 Web Services and Its Applications
WSA
Fall OCT 31, 2007
课堂讨论 Web Services and Its Applications
Li Yinsheng ( )
Institute of e-Business
Fudan University Software School

2. Case Description
This cased is produced based on examples by Sun Microsystems, Inc.
Java™ WSDP

3. Application Architecture

4. Business Workflow Scenario
Coffee Break server uses both JAXM messaging (request/response model) and JAX-RPC to communicate with its two distributors
Coffee Break server uses JAXR to send a query searching for coffee distributors that support JAX-RPC
Coffee Break server requests price lists from each of the coffee distributors –price list delivered as JavaBean component (JAX-RPC) – price list delivered as XML document (JAXM)

5. Business Workflow Scenario
Coffee Break Server creates a local database of distributors
When an order is placed, suborders are sent to one or more distributors using the distributor's preferred protocol

6. Architectural Modules
JAX-RPC distributor service
JAXM distributor service
Web server module
JAXR registry

7. JAX-RPC Distributor Service
Service interface
Service implementation
Service registration

8. JAX-RPC Distributor Service
Service Interface
package com.sun.cb;
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface SupplierIF extends Remote {
public ConfirmationBean placeOrder(OrderBean order) throws RemoteException;
public PriceListBean getPriceList() throws RemoteException; }

9. JAX-RPC Distributor Service
Service Implementation
public ConfirmationBean placeOrder(OrderBean order) {
Date tomorrow = com.sun.cb.DateHelper.addDays(new Date(), 1);
ConfirmationBean confirmation = new ConfirmationBean(order.getId(), tomorrow);
return confirmation; }
public PriceListBean getPriceList() {
PriceListBean priceList = loadPrices();
return priceList;

10. JAX-RPC Distributor Service
Service registration using JAXR
public class OrgPublisher {
public static void main(String[] args) {
ResourceBundle registryBundle = ResourceBundle.getBundle("com.sun.cb.CoffeeRegistry");
String queryURL = registryBundle.getString("query.url");
String publishURL = registryBundle.getString("publish.url");
String username = registryBundle.getString("registry.username");
String password = registryBundle.getString("registry.password");
String endpoint = registryBundle.getString("endpoint");
String keyFile = registryBundle.getString("key.file");

11. JAX-RPC Distributor Service
Service registration using JAXR
JAXRPublisher publisher = new JAXRPublisher();
publisher.makeConnection(queryURL, publishURL);
String key = publisher.executePublish (username, password, endpoint);
try { FileWriter out = new FileWriter(keyFile);
out.write(key);
out.flush();
out.close();
} catch (IOException ex) {
System.out.println(ex.getMessage()); }
} }

12. JAX-RPC Distributor Service
Messaging Model Used
Uses request/response messaging
– JAXM provider is not used
Two request/response interactions
– request: “Requests for current wholesale coffee prices”
– response: “Current price lists”
– request: “Customer orders for coffee”
– response: “Order confirmations”

13. JAX-RPC Distributor Service
Messages Being Exchanged
Pre-agreed upon Message formats in DTD's
– request-prices.dtd
– price-list.dtd
– coffee-order.dtd
– confirm.dtd
Sample Messages
– request-prices.xml
– price-list.xml
– coffee-order.xml
– confirm.xml

14. JAX-RPC Distributor Service
JAXM Client
Creating request message
Extracting information from the response message

15. JAX-RPC Distributor Service
JAXM Service
Servlet based
– PriceListServlet for price list response message
– ConfirmationServlet for order confirmation response message

16. Web Server Modules For creating dynamic contents Uses – Servlet – JSP
* Template Tag library for common look and feel
* JSTL custom tags
– JavaBeans components
* Contains business logic
* Send requests to web services
* Handles responses from web services message

17. Web Server Modules MVC Pattern
Coffee break web module is based on MVC pattern
Dispatch servlet as Controller
– Examines the request URL
– Creates and initializes model JavaBeans components
– Dispatches requests to view JSP pages

18. Web Server Modules JSP Pages and Java Beans Update order data
– JSP page: orderForm
– JavaBean: ShoppingCart
Update delivery and billing data
– JSP page: checkoutForm
– JavaBean: CheckoutFormBean
Display order confirmation
– JSP page: checkoutAck
– JavaBean: OrderConfirmations

19. Web Server Modules Servlets RetailPriceListServlet
– Responds to requests to reload the price list
– Creates a new RetailPriceList and a new ShoppingCart
– Used only by administrator
– Protected resource
– In order to load the price list, a user must authenticate (using basic authentication) and the authenticated user must be in the admin role