1. Web Services in WebLogic Server
Aaron Mulder Chief Technical Officer Chariot Solutions LLC

2. Learning Objectives In this presentation, we'll discuss
The advantages of web services
Exposing EJBs as web services in WebLogic 6.1 and WebLogic 7.0
Invoking web services from applications running in WebLogic 6.1/7.0

3. About Aaron Mulder Chief Technical Officer of Chariot Solutions
Published author (Professional EJB, and a forthcoming WebLogic 7 handbook)
Presented at JavaOne 2001/2002, and the Philadelphia Java Users Group
Member of the JSR-88 Expert Group (J2EE Application Deployment)
Contributed to open-source projects such as JBoss, OpenEJB, and PostgreSQL

4. Presentation Agenda About web services
WebLogic support for web services
WebLogic 6.1 in detail
WebLogic 7.0 in detail
Conclusions, Q&A

5. Why Web Services? Interoperability Alternatives hardware platforms
programming languages
applications
business partners
Alternatives
CORBA
RMI
Proprietary protocols (XML, binary, etc.)

6. What Are Web Services? Generic protocol, transport
For today's discussion
SOAP 1.1
WSDL 1.1
HTTP or HTTPS
JAX-RPC
Registry services
UDDI 2.0

7. What Does WebLogic Support?
First release with web services support
Tools to generate web services servlet/JSP code for stateless session EJBs and JMS destinations
Crippled tool to generate client code to invoke web services
No standards-based support

8. What Does WebLogic Support?
Improved web services support
Deployment Descriptor-based web services support
Tool to generate client code to invoke any web service (based on WSDL)
JAX-RPC support
WebLogic 8.0 ?
J2EE 1.4/EJB 2.1 web services support

9. Overview of Examples
For the rest of the presentation, we'll dig into the code and procedures
Source code is included on CD
There are no particular WebLogic Console configuration requirements
We'll focus on EJB access, as that is what J2EE 1.4 standardizes
Inportant: WebLogic client libraries can be freely redistributed

10. WL6.1: Overview Expose stateless session beans via web services
Some limitations on EJB interface
Can't expose selected methods
The easy tool doesn't support security, or apps larger than a single EJB JAR
The advanced procedure can't generate client code
Examples use WebLogic 6.1 SP3

11. WL6.1: Architecture WAR EJB JARs SOAP Servlets Session Beans Client
Error Servlet
WSDL JSPs

12. WL6.1: Developing the EJB No method overloading
Limited data types in parameters, return value
boolean
short
int
long
float
double
Boolean
Short
Integer
Long
Float
Double
String
BigDecimal
Date
Element
Document
DocumentFragment
byte[]
1-D array of these
JavaBean with these types of properties

13. WL6.1: Easy Packaging Tool
Create EJB JAR like usual
Run setEnv script in weblogic/config/domain
Use wsgen Ant task to create web services WAR and an EAR with the EJB JAR and WAR
Deploy the EAR like usual

14. WL6.1: wsgen Ant script <wsgen destpath="example-wsgen.ear"
context="/examples"
protocol="http">
<rpcservices path="myejb.jar">
<rpcservice bean="Bean1"
uri="/web-services/bean1" />
</rpcservice>
</wsgen>
Configuration Parameters:
EAR name
Web application context
Protocol (http/https)
Source EJB JAR
ejb-name from EJB JAR
EJB sub-context

15. WL6.1: Advanced Packaging
Advantages
Security settings
Multiple EJB JARs, existing WAR/EAR
Custom layout, URLs
Procedure
Configure servlets & EJB refs in WAR
Generate WSDL JSPs
Add WAR, EJB JARs to EAR
Use easy packaging to generate client

16. WL6.1: Configure the WAR Add an invocation servlet for each EJB
weblogic.soap.server.servlet.StatelessBeanAdapter
One <init-param> called ejb-ref whose value is the JNDI name of the EJB Ref
Add one error servlet in each WAR
weblogic.soap.server.servlet.FaultHandler
Add servlet mappings for each servlet
Add an <error-page>
Exception class weblogic.soap.FaultException
Location matches error servlet mapping

17. WL6.1: Configure the WAR, cont.
Add an EJB Reference for each EJB
ejb-ref name must match the argument to the invocation servlet
Add security-constraint, login-config, etc. to secure the web service
Will use WebLogic security realm like any other web application
Can separately secure the EJBs, but an insecure servlet can't invoke a secure EJB

18. WL6.1: DD Examples Too much to show here; provided on CD
Typically web.xml with all the settings described here, and weblogic.xml with EJB reference resolution
Can integrate these settings into existing deployment descriptors for existing WAR

19. WL6.1: Generate WSDL JSPs Run the setEnv script
Add EJB JAR to the CLASSPATH
Run the Remote2WSDL tool
java weblogic.soap.wsdl.Remote2WSDL -protocol http com.chariotsolutions.example.Bean1 examples/web-services/bean1 > src/web/bean1-wsdl.jsp
Remote2WSDL Arguments
Protocol (http/https)
fully-qualified remote interface name
context & URL to servlet, without leading /
redirect output to a file
check for extraneous “type-class-name” line

20. WL6.1: WSDL JSP Aliasing
Can add servlet and servlet mapping to web.xml for WDSL JSPs
<servlet>
<servlet-name>Bean1WSDL</servlet-name>
<jsp-file>/bean1-wsdl.jsp</jsp-file>
</servlet>
<servlet-mapping>
<url-pattern>/web-services/bean1.wsdl</url-pattern>
</servlet-mapping>

21. WL6.1: Configuring the EAR
Add web services WAR and EJB JAR to application configuration
<application>
<display-name>Example of Web Services</display-name>
<module>
<ejb>example-ejbs.jar</ejb>
</module>
<web>
<web-uri>example-web-services.war</web-uri>
<context-root>/examples</context-root>
</web>
</application>

22. WL6.1: Generate Client Code
Only way to generate client code is to use wsgen Ant task, and it only generates clients for web services running in WebLogic
Can use a third-party tool such as Apache SOAP or IBM Web Services Toolkit

23. WL6.1: Invoking the Web Services
Build a URL from the web app context root and servlet url-pattern
For the examples provided:
Be sure to configure a security realm or comment out the security settings in web.xml

24. WebLogic 7.0 Web Services
More options for what backs the web services (individual EJB methods, etc.)
Supports additional data types
Can interact with SOAP messages
Client need not receive a response
Generates JAX-RPC clients from WSDL
Quick-start tool from WSDL
Uses web services DD
Examples use WebLogic 7.0 SP1

25. WL7.0: Architecture WAR EJB JAR SOAP Handler Chain Client
web-services.xml
Session Beans ?
SOAP Handler
Chain

26. WL7.0: Developing the EJB Still can't expose overloaded methods
Generally same basic data types as WebLogic 6.1, but can generate or code custom XML serializers for unknown data types (such as Java Beans)
Additional built-in types include: byte/Byte, char/Character, BigInteger, Calendar

27. WL7.0: Easy Packaging Tool
Create an EJB JAR like normal
Run the setEnv script to set environment, add webserviceclient.jar to CLASSPATH
Run an Ant script with servicegen to create an EAR from an EJB JAR
Deploy the EAR
servicegen has loads of options, but still doesn't integrate well into an existing application

28. WL7.0: servicegen Ant Script
<servicegen destEar="example-servicegen.ear"
contextURI="examples" >
<service ejbJar="example-ejbs.jar"
targetNamespace="java:mypackage.name"
serviceName="Bean1"
includeEJBs="Bean1"
serviceURI="/web-services/bean1"
generateTypes="True"
expandMethods="True"
style="rpc" >
<client packageName="com.chariotsolutions.example"/>
</service>
</servicegen>

29. WL7.0: Advanced Packaging
Procedure
Develop and package the EJBs
Create the web-services.xml deployment descriptor
Package the WAR, including web.xml for security, and classes for SOAP handlers
Package the EAR, including EJB JARs and WAR
Build the client code

30. WL7.0: web-services.xml <web-services>
<web-service name="Bean1"
targetNamespace="java:mypackage.name"
uri="/web-services/bean1">
<components>
<stateless-ejb name="Bean1">
<ejb-link path="example-ejbs.jar#Bean1" />
</stateless-ejb>
</components>
<operations>
<operation method="saySomething"
component="Bean1" />
</operations>
</web-service>
</web-services>

31. WL7.0: More web-services.xml
Use embedded XML schemas with namespaces to identify custom data types (see also the autotype Ant task)
Use method parameters to support in/out parameters
Use method of “ * ” to support all methods on an EJB
Specify one-way operations
Specify SOAP processors

32. WL7.0: Package WAR & EAR web-services.xml goes in WEB-INF/ in the WAR
SOAP handler classes go in WEB-INF/lib or WEB-INF/classes
Security, WSDL URL aliasing goes in web.xml
No need for EJB refs in web.xml
EAR needs references to WAR and EJB JARs like before

33. WL7.0: Deploy EAR Deploy the EAR like normal
Web services appear in the Console under Deployments/Web Services Components
Use these URLs to access the web services and WSDL:

34. WL7.0: Client Code Run setEnv script, add webserviceclient.jar
Generate client code from the WSDL using the clientgen Ant task
<clientgen
wsdl="c:/examples/src/web/bean1.wsdl"
serviceName="Bean1"
packageName="com.chariotsolutions.example.client"
clientJar="c:/examples/dist/bean1-client.jar"
/>
Can also specify a normal URL for the WSDL

35. WL7.0: Coding a Client
Add webserviceclient.jar and client JAR to CLASSPATH
Configure JAXM/JAX-RPC system properties
Use the generated classes to invoke the Web Service
Or, use a much more complicated process to dynamically interact with arbitrary web services based on WSDL

36. WL7.0: Client Code
System.setProperty("javax.xml.soap.MessageFactory",
"weblogic.webservice.core.soap.MessageFactoryImpl");
System.setProperty("javax.xml.rpc.ServiceFactory",
"weblogic.webservice.core.rpc.ServiceFactoryImpl");
...
Bean1_Impl stub = new Bean1_Impl();
Bean1Port bean = stub.getBean1Port(username, password);
String response = bean.saySomething();
System.out.println("Bean1 said: "+response);
This client will work against the service deployed in WebLogic 6.1 or 7.0!

37. Conclusions
WebLogic 6.1 provides basic web services, but limited client generation
WebLogic 7.0 provides lots of options, but taking full advantage makes it extremely difficult to configure
WebLogic 7.0 is nearly fully Ant-script- able from client to server (WSDL?)
EJB 2.1 will be greatly appreciated when it arrives

38. How can web services ease integration challenges today?
A Final Thought
How can web services ease integration challenges today?

39. Questions?