Application Servers G Session 1 - Main Theme Legacy Application Server Technology. Dr. Jean-Claude Franchitti

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Application Servers

G22.3033-011

Session 1 - Main Theme

Legacy Application Server Technology

Dr. Jean-Claude Franchitti

New York University

Computer Science Department

Courant Institute of Mathematical Sciences

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Agenda

„ Application Servers Generics

„ Course Logistics, Structure and Objectives „ Knowledge Required

„ Application Servers Evolution „ Supporting Technology „ Expected Features

„ Related XML Technology

„ Introduction to Component Technologies „ Summary

„ Class Project Overview „ Readings

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Part I

Introduction

Application Servers Generics

Modern Application Server Properties

„ Rich/portable software

„ Middleware between pervasive devices and back-office

systems

„ Platform independent programming interface

„ Support legacy applications integration (EAI/B2Bi) „ XML-enabled

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Course Logistics

Course Web Site

„ http://cs.nyu.edu/courses/fall01/G22.3033-011/index.htm „ http://www.nyu.edu/classes/jcf/g22.3033-011/

„ Login/Password: appserv/appserv (not currently protected) „ Review syllabus

„

Textbooks

„ Building J2EE Applications with IBM WebSphere

„ Microsoft .Net Distributed Applications: Integrating XML

Web Services and .Net Remoting

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Knowledge Required

Programming Languages (g22.2110)

Operating Systems(g22.2250)

„

Programming for the WWW

Ability to program in Java

„

Some exposure to XML and associated

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Other Useful Knowledge

Web server configuration and the HTTP protocol

Scripting languages (e.g., JavaScript, Perl, TCL, etc.)

Database theory (normalization rules)

„

Web publishing

„

Enterprise applications design

„ See Session 1 Sub-Topic 1 on “Sample Enterprise Application

Design”

„ See Session 1 Sub-Topic 2 on “Sample Project Development

Methodology”

„ See Session 1 Sub-Topic 3 on “Detailed Project Development

Methodology”

Application Servers Evolution

Traditional client-server technology

„

CGI frameworks

„

Page-based extended HTML environments

Distributed object computing platforms

Java-Based

„

Object Management Architectures (OMAs)

Component-based computing environments

Web Services platforms

„

Next generation application servers (reflective,

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Part II

Supporting Technology

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„

(Network) Communication Protocols

„ e.g., TCP/IP, HTTP, RPC, GIOP/IIOP, RMI, XML,

XML-RPC, SOAP/DIME/ROPE, UDDI/DISCO, WSDL

„

Client-Server Technology

„

Distributed Object Computing

„

Component Models and Frameworks

„

Secure Messaging Infrastructures

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„

Connection

Customers (and partners) were required to have dedicated lines, leased lines, dialups, or some other access to your company.

„

Network Protocol

Customers had to use the same network protocols as the company they wanted to communicate with, TCP/IP, IPX/SPX, NetBUI, etc.

„

Hardware Requirements

Customers had to meet specific machine requirements: microprocessor speed; screen resolution; RAM; hard disk space; modem speed; etc. Customers were required to make a huge investment in hardware.

„

Operating System Requirements

The customer had to run a specific Operating System and version.

„

Software Updates

Application updates via floppy disks or CDs had to be infrequent. The customer was required to perform the costly installation or update.

Old Client/Server Model

Web Business Evolution

First it was Online Publishing

„ The World Wide Web - a Global Information Network Emerged

(The Information Superhighway)

„ The Web Browser Provided Platform-Independent Access to Information „ People Could View the Same Content Anywhere in the World

„ There was Explosive Growth in the Number of Business Web sites

„

Now it’s Online Services and Web Applications.

„ Businesses are Building Relationships with Web-based Customers „ Value-Based Services are Ensuring a Steady Flow of Web-based Traffic „ Overhead is Reduced with Automated Online Services

„ A New Global Marketplace is Emerging

-Web Applications/services are Available from Anywhere in the World 24x7

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Basic Web Applications

DB Databases Documents

Enterprise

Data

Web

Server

Client

Browser

Internet Connection

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Robust Web Applications

Presentation Tier Rich Clients (Java C/C++, VB) Web Browser

Business Logic Tier

Web Servers Application Server(s) Data Tier Databases Enterprise C/S Applications Legacy Systems Documents HTTP IIOP

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„

High Performance and Scalability

„ Benchmarks demonstrate 6000+ concurrent users, 12,000

TPM on a 4-CPU Sparc

„

High Availability & Reliability

„ Customers like E*Trade & ISN demand 24x7 reliability

with software & hardware fault tolerance

„ eBay on WebSphere

„ 30 billion transactions per day „ Over 8,000 tps!

„ Countrywide Insurance on WebSphere „ Over 20,000 tps!

Mission Critical Applications

Requirements

„

Rapid Development through Pre-built Application

& System Services

„ Proven that large-scale enterprise applications can be built

in half the time with equivalent resources

„

Enterprise Integration

„ Need for high-performance integration to databases, legacy

systems, client/server applications and ERP applications

„

Open & Extensible

„ Need for standards-based, cross-platform supporting

Windows/UNIX, JAVA/C++, CORBA/IIOP, RMI/IIOP, and .Net/COM+

Mission Critical Applications

Requirements (continued)

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Application Servers

Selection Criteria

Usability

Scalability

Security

Manageability

„ Fault tolerance, auto-deployment, communications, development environment, monitoring tools

„

Reusability

Support

Skills

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„

Legacy technology

„

Page-based extended HTML environments

„

OMA-based

„

Web Services platforms

„

MDA-based

„

Next generation

„

http://www.appserver-zone.com/guide.asp

used to list many unclassified products

Application Server Categories

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„

CGI-Perl custom environments

„

ColdFusion MX, PHP 4, ASP, JSP

„

Websphere 5.0

„

WebLogic 8.1

„

JBoss

„

Inprise, iPlanet, Sybase EAServer

Application Servers Examples

Application Packages

(SAP, PeopleSoft, Baan)

ERP, and B2Bi Suites

„

Human Resources

Sales Automation

Financial/Accounting

Retail/Point of Purchase

Manufacturing/Inventory

Supply Chain Management

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Part III

Expected Features

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Sample Features

High performance & scalability

Create applications that deliver data quickly and scale to hundreds and thousands of concurrent users.

„

Maximum availability (24x7)

Create applications that are available 24 hours a day, 7 days a week, even when you are updating them!

„

Client Independence

Access applications using web browsers or rich Java/C++ clients.

„

Rapid application development (RAD)

Develop your applications quickly and easily with pre-built system and application services, application builder, extension builder, and a variety of third-party tools.

„

Enterprise Application Integration

Connect to backend databases, existing client/server applications, and your existing legacy systems.

23 Customer

Self-Service

z on-line credit card

z customer care & billing

z portfolio management z benefits administration Business-to-Business Efficiencies z package tracking z claims processing

z supply chain management

z sales automation

Revenue Expansion

z on-line retailing, on-line trading

z loyalty programs

z travel and entertainment

What Customers are Building with it...

Value Proposition

Develop, Deploy & Manage Business-Critical Applications

Development Methodology

Develop & deploy ‘Extensions’ in Java/C++ for enterprise application integration

Develop & deploy business applications in Java/C++

Extension Builder Application Builder

Develop Deploy

• High Performance & Scalability • High Availability • Client-Independence • Rapid Development of Application Servers • Application Administration & Management

• Server & Cluster

Administrator

Internal Architecture

Client

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„

Key Administration Services

z Application Management

z Server Management

„

Key System Services

z Multi-process, Multi-threaded z Dynamic Load Balancing z Application Partitioning z Asynchronous Processing z Event Logging & Tracking z Kernel Services

z Directory Services z E-mail Messaging

Services (continued)

Application Builder

„

Rapid Development of Business Applications

z Wizards for Point-&-click Development

z Pre-built Application Services and Class Libraries (Java, C/C++) z Reusable Application Components

z Distributed Deployment of Application Components

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„

Robust Application Development Tools

z Application Logic Designer z HTML Designer z Query Designer z Project Manager z Third-party Tool Support

Application Builder

„ Advanced cluster management

„ Enterprise-wide views of all servers and processes „ Event monitoring & alerts

„ Multi-view graphical performance monitoring „ ACL, User & Group

Management „ Load balancing customization „ Application administration „ Application partitioning „ Integrated deployment

Server Administration

Application Server Business Logic Pre-built System & Application Services

Extension Builder

Extending Application Servers Functionality

Extensions

Extension Builder

(Create Custom Extensions)

Use Pre-built Extensions

• IBM MQ Series • BEA Tuxedo • IBM CICS, IMS • ERP Extensions OR • Client/server applications • Enterprise Systems • Legacy Applications • Third-party Web solutions Existing Applications and Systems

Open and Extensible

Technical Architecture

Open Client Library

Java, C/C++,VB Platforms • Sun Solaris • HP-UX • SGI Irix Extensions • TP Monitors • Legacy • Client/server OC L Data A c cess En gine E xt en si o n s Protoco l Manag er (H T T P , KC P, IIOP) W eb Connec tor s ISAPI, NSA P I, CGI Web Servers Application Server (Java, C/C++) Embedded (bundled) IONA ORB

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Part IV

Related XML Technology

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XML-Based Architectures

Presentation-Oriented Publishing Frameworks

XML-Based Application Servers

„

Message-Oriented Middleware Frameworks

Web Services Frameworks

„ Peer to Peer (P2P) Computing

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XML MOM and POP Frameworks

„ An XML support framework must include: „ XML Parser (conformity checker)

„ XML applications that use the output of the Parser to

achieve unique objectives)

POP Applications Support Frameworks

„ Objective is to “serve” XML

„ HTML generation applications are provided „ Sample solutions

„ XML::Parser module with Perl „ XML processing via Java servlets

„ e.g., IBM Alphaworks’ XMLEnabler

„ See session 2’s sub-topic 2.3.2 on “XML POP

Application Server Framework”

„ Apache’s Cocoon

„ http://www.xml.com/lpt/a/2002/02/13/cocoon2.html „ Active Server Pages (ASP) with MSXML (see

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XML POP Packaged Solutions

Enterprise Information Portal (EIP) toolkits

„

e.g., DataChannel’s XML framework

Structured content management and retrieval

systems

„

e.g.,

„ Vignette’s StoryServer

„ Gauss Interprise’s VIP’XML-Gateway „ Poet’s Content Management Suite „ Chrystal Software’s Astoria

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MOM Applications Support

Frameworks

„ Many applications can be envisioned

„ One objective is to support application integration via

XML data interchange

„ Sample solutions:

„ XML::Parser module with Perl

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XML MOM Applications

Component-based modeling

„

e.g., XML Metadata Interchange (XMI)

Enterprise Application Integration

„

Business-to-Customer (B2C) Applications

e.g., e-Commerce

Business-to-Business (B2B) Applications

e.g.,

„ XMLSolutions’ ExeterXML server

Java and the Apache XML Project

„

See related article at:

„ http://www.informit.com/content/index.asp?product_id=%7B1

1D8FB42-EC59-4F7B-8215-EDBD80F6A471%7D

„

List of XML Sub-Projects:

ƒ Xerces: XML parsers in Java, C++ (with Perl and COM bindings) ƒ Xang: Rapid development of dynamic server pages, in JavaScript ƒ Xalan: XSLT stylesheet processors, in Java and C++

ƒ SOAP: Simple Object Access Protocol ƒ FOP: XSL formatting objects, in Java

ƒ Crimson: Java XML parser derived from the Sun Project X Parser ƒ Cocoon: XML-based Web publishing, in Java

ƒ Batik: Java-based toolkit for Scalable Vector Graphics (SVG) ƒ AxKit: XML-based Web publishing, in mod_perl

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XML and Java Standards

XML is a family of technologies

„ XSL, XML Schema, XML Query, XPath, XPointer,

XLink, XML Base, DOM, CSS, XSL/XSLT, XHTML, XForms, XML Encryption, XML Key Management, XML Signature, RDF, MathML, SMIL, SVG, X3D, etc.

„

Review the current state of the XML standards at

http://www.w3c.org/XML

„

Review the current state of Java Technology and

XML (JAXP) standards at

http://java.sun.com/XML

„

Review the Java binding to DOM 2.0 at

http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113/java-binding.zip

„ DOM Level 3 still at the specification stage

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XML and Java Standards

„

Java XML Pack

„ Java Architecture for XML Binding (JAXB) „ Java API for XML Messaging (JAXM) „ Java API for XML Processing (JAXP) „ Java API for XML Registries (JAXR) „ Java API for XML-based RPC (JAX-RPC)

„

Java Web Services Developer Pack (WSDP 1.1)

„ Java XML Pack

„ JSP Standard Tag Library (JSTL) 1.0.3 „ Ant Build Tool 1.5.1

„ Java WSDP Registry Server 1.0_04 „ Web Application Deployment Tool „ Apache Tomcat 4.1.2 Container

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Java & XML Frameworks

XML Parsers

„

Xerces-J

Crimson

„

Oracle XML parser

„

XML Server-Side POP Frameworks

Cocoon

„

XML P2P/B2Bi/EAI (MOM) Frameworks

JXTA, WebMethods, etc.

Java and Web Services

„

Java Web Services Developer Pack (WSDP 1.1)

„

Java XML Pack

„

JavaServer Pages Standard Tag Library (JSTL) 1.0.3

Ant Build Tool 1.5.1

„

Java WSDP Registry Server 1.0_04

Web Application Deployment Tool

Apache Tomcat Container 4.1.2

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Java-enabled XML Technologies

XML provides a universal syntax for Java semantics

(behavior)

„

Portable, reusable data descriptions in XML

Portable Java code that makes the data behave in

various ways

„

XML standard extension

„

Basic plumbing that translates XML into Java

„ parser, namespace support in the parser, simple API for

XML (SAX), and document object model (DOM)

„

XML data binding standard extension (JAXB)

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Part V

Introduction to

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Object-Oriented Programming

Method of implementation in which programs are

organized as cooperative collections of objects

„ Objects are instances of some class „ Classes are members of a class hierarchy

„ Classes are united via inheritance relationships in which

child classes can share members of parent classes and have similar structure and behavior

„

Class

„ Language type with structure and behavior „ Named or anonymous

„ Contain member variables and methods

„

Object

„ Instance of a class with own state, behavior, and identity

More on OOP

OOP Infrastructure

„ Language Compiler and Tools „ Facilitate OOAD process

„

OOP Conceptual Framework

„ Object Model

„ Abstraction, encapsulation, modularity, inheritance hierarchy, polymorphic typing

„ OM notions can be applied to component programming „ e.g., modularity in OOP via “componentization”!

„

OOP and Component Programming are Difficult to

Separate

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More on OOP

„

Polymorphism

„ Subtype polymorphism

„ Abstract base classes with inheritance and abstract methods (C#)

abstract class A { void f(); } class B extends A {

void f() { Console.WriteLine(“B class”);} };

„ Parametric polymorphism

„ Uses template classes or functions (C++) „ Ad-hoc polymorphism

„ Achieved via operator and function overloading (+ -> concatenate)

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Components

„

Cannot exist without a component infrastructure

„ Compilers use different name calling conventions

„ Must introduce a component infrastructure that hides the

underlying complexity of different tools and systems used when creating and deploying components

„

Neither an object nor a class nor a combination

„ May include many classes

„ Component exports interfaces rather than methods „ Interfaces do not always have 1-1 correspondance with a

class

„

Not a module (closed static unit that encapsulates

embedded abstractions)

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Components

„

A component interface is the unit of component

behavior in which some logically grouped methods

are exposed to clients

„

Component properties

„ Contain compiled program files

„ Package compiled programs in a file that has a format

known to the component infrastructure (e.g., DLL, CAB, JAR, EXE)

„ Language neutral

„ EJB? -> use software bridge to use JavaBeans from VC++

„ e.g., ActiveX bridge (component infrastructure)

„ Registers with Component infrastructure via a unique name „ CB development tools may use introspection to explore

components at runtime

Component Infrastructures & Models

Component Infrastructure

„ Set of system services based on a component standard that

ensure the properties of the component are immutable and enables rules of component composition and interaction

„

Component Model

„ Defines component interaction and composition standards

„

Components Subsume Standards, Component

Infrastructures, Tools, and OOAD

„

Enterprise assurance

„ Performance

„ Concurrency (stateful/stateless components), caching of data or component, distributed transaction management (many components may modify databases)

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Part VI

Conclusion

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Summary

„

Enable Rapid Development of Business Applications

Provide Industry Leading Performance & Scalability

Provide High Availability & Reliability

„

Enable Enterprise Application Integration

Allow Client-Independence

(HTML, Java, C++, VB)

„

Provide Open & Extensible Architecture

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Class Project

Project Description

„ The project focus is two-fold:

„ Based on a framework-based enterprise application of your choice (e.g., “multi-channel online community platforms”), you will implement common facilities and application-level services on top of various types of application server technologies to support the various aspects of your chosen application

„ As you transition from one platform to another you will study and develop model-based migration and interoperability tools that leverage off of the cutting-edge concepts subsumed by modern Model Driven Architectures (MDAs)

Readings

Readings

„ Handouts posted on the course web site

„

Project Frameworks Setup (ongoing)

„ Apache Web Server (www.apache.org) „ Perl

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Assignment

Assignment:

„ #1a: Investigate legacy application server development

environments. Write a short report that documents your findings and recommendations with respect to selection criteria in support of legacy development environments for application server technology

„ #1b: Come up with a framework-based business

application and implement it on top of the core technology supplied as part of the homework #1 documentation

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Next Session:

Page-Based Application Servers (Part I)

„

ColdFusion 6.1/MX Environment

PHP 4 Environment