New BEA Technologies To Deliver Web Based Applications

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New BEA TechnologiesTo Deliver Web Based
Applications

• WLS 7.0, Web Services and Cajun

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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Introductions

• Who am I?
• Quick survey about you
• By show of hands, how long have you been
  programming in Java?
• Ask questions!

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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What is BEA WebLogic Workshop?

• BEA WebLogic Workshop is a new integrated
  development framework for the BEA WebLogic
  Platform
• WebLogic Workshop makes it incredibly simple for
  application developers to build enterprise class
  web services
• WebLogic Workshop enables teams of developers
  with different skill sets to utilize the proven
  reliability, and scalability of BEA WebLogic
  Server
• WebLogic Workshop was formerly referred to by the
  code name Cajun

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Workshop Makes it Simple

• Building applications on the J2EE platform is
  hard
• Highly object oriented
• Need to understand the J2EE component model just
  to build simple applications
• Many rich and complex APIs overkill for most
  common cases
• All the low level details are exposed
• Deploying applications is tedious and time
  consuming
• Workshop puts the focus on application logic
• Visual metaphor for building web services
• Declarative, annotated code exposes web service
  functionality
• Server-side controls encapsulate J2EE APIs
• Plumbing code managed by runtime framework

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Enterprise Class Web Services

• What is a Web Service?
• A software component or application exposed
  through standard XML and Internet protocols
• Three key standards
• Simple Object Access Protocol (SOAP)
• Web Services Definition Language (WSDL)
• Universal Description, Discovery, and Integration
  (UDDI)
• The stock quote example

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Misunderstanding Web Services

• The common understanding of web services is
  limited
• Function calls over the internet
• Simple, synchronous, request-response model
• This is interesting, but only the tip of the
  iceberg

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Principles of Web Services

• Three key principles for that make Web Services
  so promising are a further move towards
• Loose coupling
• Coarse grained calls
• Asynchronous systems
• Providing potential to solve previously
  unaddressed (or unresolved) integration problems
  in the enterprise

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Adopting Web Services

• For Web Services to reach its true potential
  certain requirements must be met
• Standards based
• Business level integration
• Flexible architecture designed for extensibility
  and change
• Accommodate internal and external integration

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Enterprise Class Web Services

• Web Services allows for this architecture
• But you need the right programming model to make
  it easy to build applications this way
• Many moving parts at the standards layer (SOAP,
  WSDL, UDDI)
• Not easy to think asynchronously
• Plus, you need a reliable, available, scalable
  platform that lets you deploy these web services
  in the enterprise
• Transactions
• Connection pooling
• Caching
• Security

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BEA WebLogic Workshop Value

• A standard Java environment that allows
  developers of all skill sets to take advantage of
  J2EE
• An event based approach and programming model
  that makes it easy to fully leverage the power of
  Web Services
• A way to maximize the development organization
• One standard platform (everyone can play on J2EE)
• Enables developers to focus on skill appropriate
  tasks
• Reduce support, training, operations burden on IT

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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BEA WebLogic Workshop IDE

• Has two main views
• Design View visual metaphor for building a web
  service
• Used to paint a picture of a business events
  execution
• Developers hang business logic on picture without
  worrying about objects and interfaces
• Shows available operations, controls and element
  properties
• Source View where you write the code
• Syntax highlighting, auto completion, squiggly
  underlined errors
• Two-way code editing between views
• Creates a JWS file that defines the business
  logic of a Web Service

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Workshop IDE Design View
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Workshop IDE Source View
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Cajun IDE Test ViewOverview

• Summary of web service operations
• WSDL, .CTRL, Java Proxy to invoke this web service

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Cajun IDE Test ViewConsole

• Internal operations (clear log, clear deployed
  beans)

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Cajun IDE Test ViewTest Form

• Exercise all functions
• View a log of all messages in and out

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JWS Files

• Java Web Service (JWS) files link the design and
  runtime environments
• IDE generates little Java code
• Javadoc annotations before methods, classes, and
  variables identify Workshop functionality

/ _at_jwsoperation _at_jwsconversation
phasestart _at_jwsmessage-buffer
enabletrue / public void getQuote(int age,
String gender, String ssn, int policyAmount) //
Your code goes here
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WebLogic Workshop Architecture
Workshop Run-time Framework
BEA WebLogic Server
JMS
EJBs
JDBC
JWS File Java code Annotation
Run-Time
Design Time
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Workshop Run-time Framework

• Reads the javadoc annotations in the JWS file and
  generates the Web Service
• JSP like model (compilation done for you)
• Automatically generates test environment, creates
  WSDL description, Java proxy
• Automatically handles deployment
• Produces standard EJB/J2EE under the hood

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Workshop Run-time Framework

• Generated code depends on sophistication of
  service
• Generally
• Stateless session bean handles web service
  dispatch of incoming messages
• Entity bean manages web service state
• Conversations, identify member variables should
  be persisted
• Message queue is created to support message
  buffers and timer controls
• Message driven bean supports message buffers

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Workshop Run-time Framework

• The runtime framework also handles many issues
  not directly related to deploying a web service
• Debugging (remote debugging against deployed web
  service)
• Conversion from JWS to CTRL or WSDL and visa
  versa
• Identifies design time errors for the IDE

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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JWS Java Web Service

• JWS files are Java classes that define business
  logic for a single web service that include
  WebLogic Workshop Javadoc extensions
• Javadoc is an unobtrusive way to extend Java
  without changing the language
• Simple (developers dont have to maintain or try
  to understand code they didnt write)
• Rich in semantic meaning (use a message buffer,
  make this conversational)
• Tells the IDE what to display
• Tells the runtime what is needed to implement and
  run
• Working to make JWS a J2EE standard

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JWS Annotations

• Annotations can appear
• Before methods / callbacks
• Before service / control definition (i.e., before
  Java class/interface)
• Before control instances
• Always in a Javadoc comment / /
• Always apply to the Java thing that immediately
  follows them.
• Always begin with _at_jws
• Usually are of a tag/attribute format
• _at_jwstimer timeout5 seconds

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Property Summary Methods

• _at_jwsconversation Indicates how a method
  participates in a conversation (stateless, start,
  continue, finish)
• _at_jwsmessage-buffer Indicates whether the method
  should use a message buffer (JMS queue)
• _at_jwsprotocol Indicates how this method receives
  messages, via http, http forms, or JMS and how it
  is enveloped, raw XML, SOAP-RPC, SOAP-doc/literal
• _at_jwsparameter-xml / _at_jwsreturn-xml Indicates
  how XML messages should be converted to Java and
  visa versa

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Property Summary Service

• _at_jwsprotocol Same as for methods, but creates
  default for service
• _at_jwsconversation-lifetime Indicates a timeout
  and max life time, after which conversational
  state will be removed
• _at_jwstarget-namespace Indicates the target
  namespace for messages sent to this service

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Callback interface

• Two approaches to asynchronous messaging
• Polling every 5 seconds the client asks are
  you done yet
• Callbacks the web service proactively notifies
  the client when an event occurs
• Callbacks are implemented as a SOAP invocation
  from service to client
• i.e., there is a web service exposed at the
  client as well
• Handled through callback interface

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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Control Introduction

• Goal of controls is to make it easy for
  developers who arent J2EE or Java experts
• Simplifies APIs for the common case
• Exposes external resources in friendly ways
• Manages lifetime and shutdown
• All controls look like local objects with methods
  and callbacks
• Behavior of controls is customized through
  properties Javadoc annotations as we have seen
  so far

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Using Controls

• Using controls in JWS files is extremely simple
• A Java variable name
• Marked with _at_jwscontrol
• Thats it!
• Framework will instantiate control instance
• Framework will hookup callbacks
• Simple naming convention to handle callbacks from
  controls
• ltcontrolnamegt_ltcallbacknamegt(ltparametersgt)
• Ex delayTimer_onTimeout()

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Controls CTRL files

• CTRL files are Java interfaces that define the
  interface to a control
• 5 Control super-types
• Database, web service, timer, JMS, EJB
• CTRL file format used for all 5 types, but actual
  CTRL file may look very different
• Each CTRL file defines a specialized class of a
  type of control extends the base interface
• Each control class can be instantiated many times

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DB Control

• Database control lets you connect to any JDBC
  data source
• Data source must be predefined through WLS
  console
• Methods tie SQL statement to Java function
• Smart datatypes
• Key Properties
• _at_jwsconnection Sets JNDI name of datasource
• Methods look like
• / _at_jwssql statement"DROP TABLE customer" /
• public void dropCustomerTable()

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Timer Control

• Timer control provides an easy interface to time
  events service gets callback when time elapses
• Useful for rendezvous, timeouts, polling
• Generally not subclassed (i.e., no CTRL file)
• Key properties
• _at_jwstimer Used to set timeout and repeat times
• Key Functions
• start() starts a timer
• stop() stops a timer
• reset() resets the timer to the original state

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Service Control

• Gives access to any web service defined by a WSDL
  Java interface on top of a WSDL
• Works for both synchronous and asynchronous
  services
• Works with .NET, Apache, IBM, WLS web services
• Key Properties
• _at_jwslocation Defines the URL on which the
  webservice is deployed
• _at_jwswsdl A link to the WSDL that defines this
  web service (usually inline)
• Methods look like
• Basically the same as in a JWS file -same
  properties same callback interface style

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EJB Control

• Makes locally and remotely deployed EJBs look
  like local classes
• Auto-creates session beans
• Caches bean instance for lifetime of control
• JNDI lookup and interface casting are unnecessary
• Key Properties
• _at_jwsejb Names home and remote interfaces
• Methods look like
• No methods! Interface extends from home and
  remote interfaces of EJB

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JMS Control

• Makes it easy to send and receive messages from
  JMS queues
• Can use general purpose put/get or add named
  functions with maps
• Takes specific arguments and generates XML
  document
• Get callbacks when messages appear on queue
• Works with queues or topics
• Key properties
• _at_jwsjms Defines send and receive queue JNDI
  names as well as JNDI name for connection factory
• Methods look like
• Named methods with XML maps for the message, JMS
  properties or both

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Agenda

• What is WebLogic Workshop? (Cajun)
• Workshop architecture
• Design-time IDE
• Run-time Framework
• Java Web Service (JWS) Files
• Asynchronous web services framework
• Controls (CTRL Files)
• XML Mapping Script

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XML Maps

• XML Maps were designed as a declarative way to
  map from Java to XML and visa versa
• Parameter-xml specifies how xml messages are
  converted into parameters and visa versa
• Return-xml specifies how xml messages are
  transformed into the return value of a Java
  method and visa versa
• Simple variable substitution with syntax

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XML Maps (cont)

• Few special tags with XML maps beyond simple
  value use
• xmmultiple
• Allows you to handle repeating XML constructs
• /
• _at_parameter-xml xml-map
• ltordergt
• ltitem xmmultiple"String desc in
  descriptions, int qty in quantities"gt
• ltdescriptiongtdesclt/descriptiongt
• ltquantitygtqtylt/quantitygt
• lt/itemgt
• lt/ordergt
• /
• void submitOrder(String descriptions, int
  quantities)

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XML Maps (cont)

• xmuse
• Allows you to call out to XML Script
• ltxmuse call"com.myco.MyScript.mymap(int a,
  MyStructure b)"gt
• OR
• com.myco.MyScript.mymap(int a, MyStructure b)

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XML Script

• XML Script is an enhanced version of XML script
  that makes XML a native citizen
• Goal is to avoid necessity of programming to the
  DOM
• Access XML like a class very natural syntax,
  operator support, etc.
• Invoke script with xmuse
• Two functions
• function fromXML (xml) Converts from XML to Java
• function toXML (args) Converts from Java args to
  XML

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XML Data

• Problem Programming with XML directly is too
  clumsy
• Prior approach Automatic data binding
• SOAP RPC via XML
• XML Schema XML data types
• WSDL IDL for XML data
• JAXB Java-XML type serialization
• But Where is the data?
• The RPC trap hiding the data means exposing the
  system implementation, and results in fragile
  integration.
• Just the opposite of the loose coupling that is
  required!

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WebLogic Workshop Schedule

• Public beta happening now!
• Download from www.bea.com
• Workshop GA 1st half of 2002 (Late May)
• Pricing / Packaging will be announced at that time

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How business becomes e-business