Raspberry Pi 5: Challenges and Solutions in Bringing up an OpenGL/Vulkan Driv...
Prakash Narayan Killer S O Aapps Using J2 E E
1. This Presentation Courtesy of the
International SOA Symposium
October 7-8, 2008 Amsterdam Arena
www.soasymposium.com
info@soasymposium.com
Founding Sponsors
Platinum Sponsors
Gold Sponsors Silver Sponsors
2. SOA & Java EE:
Developing killer SOA
applications using the Java EE
Platform
Prakash Narayan
Sun Microsystems
3. Goal
Visualizing and developing composite
applications using BPEL, SOA and
Java EE
2
5. Applications
• Developers need to build end-to-end applications
> Front-end user interfaces
> Middle-tier business logic
> Back-end resources
• With the right approach, developers can...
> Reuse existing parts
> Build new parts
> Glue old and new parts together
• With the wrong approach, developers must...
> Reimplement functionality existing elsewhere
> Spend massive effort to evolve applications
4
6. Applications
• Real-world applications are...
> ...not Web applications
> ...not Java EE applications
> ...not Swing forms
> ...not Web services
> ...not BPEL processes
> ...not SOA
> ...not JBI
> ...not RDBMSs
> ...not (your favorite technology)
• Real-world applications use many or all of these
5
7. Applications
• Traditional model of application development
> Point technologies, products, and APIs
> For example: EJB, Spring, Hibernate, JSF, Servlets, Struts, etc.
> Lots of glue written by developers
> Requires a great deal of expertise & time
> Inflexible
6
8. Composite Applications
• A way to compose applications from reusable parts
• Comprised of heterogeneous parts
> Some existing parts
> Some new parts
> Some glue to connect these parts
• Composite applications are Applications!
> Composite applications != SOA
• Composite applications employ SOA principles
> Features exposed as Web services
> Standards-based interaction between services
> Are themselves composable 7
10. What Are Services?
• Black-box components with well-defined interfaces
> Performs some arbitrary function
> Can be implemented in myriad ways
• Accessed using XML message exchanges
> Using well-known message exchange patterns (MEPs)
• Services are self-describing
• Metadata in the form of WSDL describes...
> Abstract interfaces
> Concrete endpoints
9
11. What Can Services Do?
• Perform business logic
• Transform data
• Route messages
• Query databases
• Apply business policy
• Handle business exceptions
• Prepare information for use by a user interface
• Orchestrate conversations between multiple services
• …
10
12. How Are Services Implemented?
• Enterprise JavaBeans™ (EJB™) technology
• BPEL
• XSLT
• SQL
• Business rules
• Mainframe transaction
• EDI transform
• Humans (yes, really!)
• …
11
15. Purchase Service Functions
WS WS
DL/
Buyer DL/
Supplier
Soa
Endpointp Soa
Endpointp
Buyer
BPE Supplier
BP E
L
Conversation L
Conversation
E JB
Transaction Fees
Rout
ing T
Supplier Routing
abl
e
XQ
Supplier
uer
y
Selection XSL
Product
T
Conversion
R
Buyerule
Credit
14
16. Service Oriented Architecture (SOA)
• An architectural principle for structuring systems
into coarse-grained services
• Technology-neutral best practice
• Emphasizes the loose coupling of services
• New services are created from existing ones
in a synergistic fashion
• Strong service definitions are critical
• Services can be re-composed when business
requirements change
15
17. Benefits of SOA
• Flexible (Agile) IT
> Adaptable to changing business needs
• Faster time to market
> Reuse existing code
> Minimize new development
• Business- and process-driven
> Enables new business opportunities
• Greater ROI
> Leverage existing IT assets
16
19. Java EE 5 Overview
• Key development features
> EJB 3.0
> Annotated “plain old Java object” (POJO) Web services
> Powerful Java Persistence API (JPA) for O-R mapping
> JAX-WS 2.1 and JAXB 2.1
> Samples and blueprints
• Open ESB Starter Kit
> Java Business Integration (JBI) runtime
> BPEL service engine
> SOAP-over-HTTP binding component
• GlassFish V2
18
20. Java EE Services
• Use EJB 3.0 to develop standards-based worker
services
> Perform business logic
> Access JDBC resources
> Call other Web services, including BPEL processes
> Transactional
> Secure
• JAX-WS 2.1 and JAXB 2.1
> Full support for XML Schema
> Document-centric services
• Call these services from BPEL processes
19
21. EJB 3.0 Example
@Stateless()
@WebService()
public class LoanProcessor {
@WebMethod
public String processApplication(...,
@WebParam(name="applicantAge") int applicantAge,...) {
int MINIMUM_AGE_LIMIT = 18; int MAXIMUM_AGE_LIMIT = 65;
String result = "Loan Application APPROVED."
if (applicantAge < MINIMUM_AGE_LIMIT) {
result = "Loan Application REJECTED - Reason:
Under-aged "+applicantAge+". Age needs to be "+
over"+MINIMUM_AGE_LIMIT+" years to qualify.";
return result;
}
...
}
} 20
23. Need for Business Process
• Developing the web services and exposing the
functionality (via WSDL) is not sufficient
• Example:
> Concert ticket purchase Web service has 3 operations,
which need to be performed in the following order
> Getting a price quote
> Purchase a ticket
> Confirmation and cancellation
• We also need a way to orchestrate these functionality
> Sequencing
> Conditional action
22
24. Business Processes
• Any technology for implementing real-world
business processes needs to...
> Coordinate asynchronous communication between
services
> Correlate message exchanges between partners
> Exchange messages in a universal form
> Process activities in parallel
> Manipulate/transform data between partners
> Support long-running business transactions
> Handle exceptions
> Provide compensation to undo previous actions
23
25. What is BPEL?
• BPEL = Business Process Execution Language
> XML-based language used to specify business
processes based on Web services
> Orchestrates partner Web services
• BPEL processes describe...
> Long-running, stateful, transactional conversations
• BPEL is one language for implementing a service
> A BPEL service is itself a WSDL-described service
> Can be used from other services or BPEL processes like
any other Web service
• BPEL processes are easy to write and change
24
26. What is BPEL?
• Cannot “do” much without other services
> Orchestrates other WSDL-described Web services
> Can't access non-Web service components
> Other partner services do the real work
> These are called functional services or worker services
• Excels at...
> Parallelism
> Long-running conversations
> Sending and receiving Web service messages
> Complex decision logic
> Fault handling and compensating logic
25
27. BPEL: Relationship to Partners
WSDL
Partner Service
Partner Service
Partner Service
Orchestrating Process
(BPEL) Partner Service
26
28. BPEL: Relationship to Partners
WSDL Inventory
Checker Service
Credit checker
Service
Customer
Service
Orchestrating Process Another Partner
(BPEL) Service
27
29. Example Business Process
Receive <PO> <sequence>
Invoke <InventoryService> Invoke <CreditService> <flow>
Reply <Invoice> </sequence>
28
31. BPEL Works With WSDL
• Web services are described in WSDL
> Operations are message exchanges
> Each operation represents an individual unit of action
• We need a way to orchestrate these operations with
multiple web services in the right order to perform a
Business process
> Sequencing, conditional behavior etc.
• BPEL provides standard-based orchestration of
these operations
30
32. BPEL “Fixes” WSDL
• WSDL describes an unordered set of operations
> Operations are grouped as interfaces
> Operations are individual message exchanges
• Semantics of the interface are missing in WSDL
> Order of invocation
> Concurrency
> Choreography with external entities
• BPEL can supply these missing semantics
31
34. NetBeans IDE 6.1
● Support for composite applications in NetBeans 6.1
● Design BPEL business processes to orchestrate:
● Java EE Web services
● External Web services
● Other BPEL processes
● Develop secure, identity-enabled Java EE Web
services
● Visualize, analyze, and edit real-world XML
Schema, WSDL, and XML instance documents
● Download: http://www.netbeans.org
33
35. Web Service Orchestration
● Visually author BPEL 2.0 business processes with
the BPEL Designer
● Step-through debugging support
● Built-in testing capability for unit testing
● “Beyond syntax” validation of Schema, WSDL, and BPEL
● BPEL Mapper
● Visually create complex XPath expressions without coding
● Deploy to the built-in BPEL engine
● JBI-based BPEL service engine + SOAP/HTTP bindings
● Running within the bundled GlassFish V2 Server
34
37. BPEL Module Project
• BPEL Module project is a group of source files
which includes
> XML Schema (*.xsd) files
> WSDL files
> BPEL files
• Within a BPEL Module project, you can author a
business process compliant with the WS-BPEL 2.0
language specification.
• Will be added to a Composite application as a JBI
module
36
38. Composite Application Project
• Composite Application project is a project whose
primary purpose is to assemble a deployment unit
for the Java Business Integration (JBI) server
> BPEL Module projects must be added to a Composite
Application project in order to be deployed to the BPEL
runtime.
• The Composite Application Project can also be
used to create and execute test cases that can then
be run, in JUnit fashion, against the deployed BPEL
processes.
37
39. Composite Application Project
• With a Composite Application project, you can:
> Assemble an application that uses multiple project types
(BPEL, XSLT, IEP, SQL, etc.)
> Configure external/edge access protocols (SOAP, JMS,
SMTP, and others)
> Build JBI deployment packages
> Deploy the application image to the target JBI server
> Monitor the status of JBI server components and
applications
38
41. Summary
• SOA enables flexible and agile enterprise
application architecture
• Services can be created and used using Java EE
• BPEL is a service orchestration language
for creating composite applications
• Services can be re-implemented using other
technologies as long as service interfaces
are preserved without changing consumers
• Java Business Integration (JBI) is the enabling
infrastructure
40
43. Call to Action!
• Download NetBeans IDE 6.1 :
http://download.netbeans.org/netbeans/6.1/final/
• Join Sun Developer Network (SDN) for up-to-date
SOA information:
http://developers.sun.com
42