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Application ServersG22.3033-011

Session 11 - Main ThemeXML-Based Capabilities

in Component-Based Environments

Dr. Jean-Claude Franchitti

New York UniversityComputer Science Department

Courant Institute of Mathematical Sciences

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Agenda

Channel Independence and Pervasive DevicesConnected Devices

XML in Component-Based Development EnvironmentsXML and JavaBeans/EJBsDeployment Descriptors for OMA ServicesMore on the OMA Persistence Service

EAI EnvironmentsB2Bi Environments (e.g., WebMethods Framework)SummaryReadingsAssignment #8 (will be handed out on 11/26, due: 12/10)

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Summary of Previous Session

Web-Enabling Facilities (continued)Java Web Start (JWS)

COM / DCOM Component Model and OLECOM+ MTS Services: Transactions and SecurityCOM+ Message QueuingSummaryReadingsAssignment #7 (continued)

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Application Servers ArchitecturesApplication Servers for Enhanced HTML (traditional)

a.k.a., Page-Based Application ServersMostly Used to Support Standalone Web Applications

New Generation Page-Based Script-Oriented App. ServersFirst Generation Extensions (e.g., Microsoft IIS with COM+/ASP)Servlet/JSP EnvironmentsXSP EnvironmentCan now be used as front-end to enterprise applicationsHybrid development environments

Distributed Object Computing PlatformsProvide an infrastructure for distributed communications enablingStill need to merge traditional web-oriented computing with object computing

Object Management ArchitecturesDOC Platform + APIs to reusable services and facilities

OMAs + Component Models -> J2EE, CCM, DNAMDAs with Web Services- and Channels/B2Bi-Enabling services

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Part I

Connected Devices

Also See Session 6 Handout on:“The Basics of the Palm Platform and the PalmOS Emulator”

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XML Tools for Information Appliances

See http://www.topxml.com/java/articles/javaxml/3.aspJava Soap library

KVM kSOAP (http://ksoap.enhydra.org/)

Environment Needed to Run XML-Based Java ApplicationsJava KVM for J2ME

Java Kilobyte Virtual Machine (KVM) designed to operate with as littleas 160 to 512 KB of memory

NanoXMLLightweight DOM-style XML parser and document generator

Palm OS Emulator (POSE)Software that emulates the hardware of different Palm devices (Palm III,Vx, VII, etc.)Can be used as a unit testing platform

Also See http://webdev.apl.jhu.edu/~rbe/kvm/

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Sample Palm ApplicationBeaming contact information from a custom Palm database

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Part II

XML in Component-Based Environment:(1) XML and JavaBeans/EJBs

(2) Deployment Descriptors for OMA Services (3) More on the Persistence Service

(focused on EJBs as CCM is nascent)

Also See Session 6 Handouts on:“Enterprise JavaBeans Patterns”

“Persistence in EJB Frameworks”“Efficient CMP Development”

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XML Support for JavaBeans and EJBs

XML and JavaBeans integratione.g., BML, Coins, etc.

JavaBeans and EJB state persistence using XMLXML serialization for Java (e.g., Koala, etc.)

XML Application Services as JavaBeans/EJBse.g., Parsing, rendering, querying, messaging beans

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Towards XML Model Based Computing

Step 1: Document Object ModelStep 2: XML Data BindingStep 3: Standard XML Information ModelsStep 4: XML Application Services Frameworks

Processing, Rendering, Querying, Secure Messaging

Step 5: XML-Based “Web Object Model”Web Services Architecture

Step 6: XML Model Driven Architectures (to come)

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EJB Component/Programming Model

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Entity Beans in EJB Application ServersRepresent sets of data (all or part of a database table or a view)Functionality limited to creation, update, and deletion of dataManage persistence of dataMaintained in a cacheCan be container or bean managed

Container-managed beans are under the control of an applicationserver for persistence and transaction managementContainer-managed beans are restricted in the type andcomplexity of data they can manageBean-managed beans rely on user provided code for persistenceand transaction management

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Session Beansin EJB Application Servers

Handle the business logic of EJB applicationsMay use multiple entity beans to gather application data

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Anatomy of a CMP BeanEJB remote interface (extends javax.ejb.EJBObject)

Contains method signatures for any method that accesses or modifies datastored in the bean

EJB remote implementation (implements javax.ejb.EntityBean)Provides an implementation of all the methods defined in the remote interface,in addition to methods required by the application server

EJB home interface (extends javax.ejb.EJBHome interface)Declares method signatures for any method that creates new instances of thebean, and for all methods that are used to retrieve instances of the bean (findermethods

EJB keyContains the unique primary key implementation for the beanany class that is a legal value type in RMI-IIOP

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Anatomy of a CMP Bean(continued)

EJB finder helper interface (optional)Contains one static java.lang.String field for each finder method declared inthe EJB home interfaceStrings are initialized with SQL queries executed dynamically when beaninstances are retrieved in a finder methodSome server ignore this file and put queries in XML deployment descriptorsusing proprietary query language formats

Deployment descriptor (XML -> serialized data object)Names of EJB classes/interfaces, list of persistent fields, etc.

Database scriptsApplication server may generate them

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EJB Generation(e.g., IBM EJBMaker, BEA WebGain Studio)

<?xml version="1.0"?> <!DOCTYPE ejbmaker SYSTEM "ejbmaker.dtd"> <ejbmaker> <!—default attributes for beans --> <transaction-attr>TX_REQUIRED</transaction-attr> <isolation-level>SERIALIZABLE</isolation-level> <run-as-mode>SPECIFIED_IDENTITY</run-as-mode> <re-entrant>false</re-entrant>

<!—A Simple Account CMP entity EJB --> <bean name = "Account" type = "entity"> <persistent_field dt="int" col_dt="INTEGER"> ACCTNUMBER </persistent_field> <persistent_field dt="java.lang.String" col_dt="VARCHAR(13)"> SSN </persistent_field> <persistent_field dt="double" col_dt="DOUBLE"> BALANCE </persistent_field> <finder_method name="findNegativeAcct"> <sql> SELECT * FROM EJB.ACCOUNTBEANTBL WHERE BALANCE &lt; 0 </sql> </finder_method> </bean> </ejbmaker>

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Container Managed Persistence Architecture

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Bean Managed Persistence Architecture

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EJB Development Approach 1

Handcode Everything: EJB remote interface EJB remote implementation EJB home interface EJB key EJB finder helper interface Deployment descriptor Database scripts

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EJB Development Approach #2:Handcode the Bean and Descriptor

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EJB Development Approach #3:Graphical Bean and Descriptor Generator

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Four Patterns for Managing Persistence

Pattern Entity Mgt. UsesEntityBeans

UsesSessionBeans

1. Container-managedEntity Beans withSession Beans

Container Yes Yes

2. Bean-managedEntity Beans withSession Beans

Bean Yes Yes

3. Entity Beans Only Container Yes No*4. Session Beans Only N/A No Yes* Session beans are used in this example for complex databaseinteractions, but they do not serve as a front-end for Entity beans.Instead, they access the database directly as an Entity bean would.

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Container-Managed Entity Beans + Session Beans

EntityManagement

Uses EntityBeans

UsesSessionBeans

Container Yes Yes

DatabaseJDBCSessionBeansClient

Application Server

EntityBeans

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Beans-Managed Entity Beans + Session Beans

EntityManagement

Uses EntityBeans

UsesSessionBeans

Bean Yes Yes

DatabaseJDBCSessionBeansClient

Application Server

EntityBeans

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Entity Beans Only

EntityManagement

Uses EntityBeans

UsesSessionBeans

Container Yes No

Database

JDBC

Client

Application Server

EntityBeans

JDBCSessionBeans

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Session Beans Only

EntityManagement

Uses EntityBeans

UsesSessionBeans

N/A No Yes

DatabaseJDBCSessionBeansClient

Application Server

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Performance Characteristics

Max

Avg

90th

Min

StdD

ev

0.001.002.003.004.005.006.007.008.00

Pattern Comparison400 users, 50 iterations, 4 server

instances/200MB

S e ssion Only 6.36 0.20 0.15 0.02 0.612

Cont a ine r Ma na ge d 6.74 0.31 0.79 0.04 0.706

Be an Mana ge d 7.02 0.31 0.95 0.04 0.687

Ma x Avg 90t h Min S t dDe v

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Performance Characteristics(continued)

Max Avg 90 th MinStdDev

0.001.002.003.00

4.005.00

Pattern Comparison100 users, 50 iterations, 4 server

instances/200MB

Entity Only 4.49 0.30 0.35 0.08 0.426

Container Managed 1.52 0.06 0.07 0.04 0.112

Max Avg 90th Min StdDev

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SQL Statements v.s. Finder Methods

Max

Avg

90th

Min

StdD

ev

0.002.004.006.00

8.00

10.00

SQL vs. Finder Method Comparison (for getting lists of data)

SQL 5.54 0.20 0.15 0.04 0.571

Finder Methods 9.99 1.06 2.92 0.05 1.457

Max Avg 90th Min StdDev

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Summary of Findings

Pattern 1:(better choice)Great for design and flexibility

Good separation of presentation, data, and business logicFast time to market

Pattern 4:Best for performance and throughput

Pattern 3:Faster time to market than pattern 1

No need to code session beansProhibitive performance cost

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Part III

EAI and B2Bi:Enterprise Application Integration

and Business to Business Integration Also See Session 11 Presentations:

“Enterprise Application Integration (EAI)”“Practical Application of EAI”

“The STP and T+1 Application”

and the Session 11 Handout on:“Enterprise Application Integration (EAI)”

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XML & DBMSs ComparisonBoth separate data from rendition/presentation infoSimilar languages

DBMSs: Forms and Reporting, DDL, DQL, DCLXML: XSL, XQL, and processing instructions

No DML in XMLXML is paired with a scripting or programming language

Validation capabilitiesDBMSs: datatyping, relationship constraintsXML: data type validity and semantic consistency checks

XML can handle data too complex for some databasesXML interchangeable form of data vs. multidatabases

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MOM Application Development Tools

Serializing Java objects into XML usingreflection

Sims Computing lightweight XML messagingframework (based on JMS)xmlBlaster Message Oriented Middlewareproject

MOM platform that uses XML for the messagemeta-data and quality of service informationMessages can be filtered using XPath expressionswhich match against the XML header document

Developing MOM applications using theSAX/DOM APIs

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Architecture of an XML MOMApplication Server

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Sample XML Application Flow

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EAI-Based Architectures

Reliable Messaging

Bus. Process Modeling & Automation

Data Transformation

System Administration & Monitoring

Transaction Management

Metadata Management

Security Dev.Tools

Application A

dapters (E

RP, C

RM

, APS, L

egacy, …)

Technology A

dapters (D

B, X

ML

, HT

TP, file, …

)

WebApplication Server

E-BusinessTrading Partner

ERP System

CRM or SFAApplication

Legacy Application

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Comparison of EAI Packages

Product Vendor Oper

atin

g Sy

stem

Proc

ess M

odeli

ng T

ools

Relia

ble M

essa

ging

Data

Tra

nsfo

rmat

ion

Tran

sact

ion

Mgm

tMe

tada

ta M

gmt

Scala

bilit

ySe

curit

ySy

stem

Adm

inist

ratio

nBu

sines

s to

Busin

ess

Deve

lope

r Too

lsPr

e-Bu

ilt P

roce

ss M

odels

Appl

icatio

n Ad

apte

rsTe

chno

logy

Ada

pter

sMa

infra

me A

dapt

ers

Unified ApplicationsArchitecture (UAA)

CrossWorldsSoftware NS 5 4 5 4 5 4 3 3 3 3 5 5 3 3

BusinessWare VitriaTechnologies NSH 4 5 4 5 5 5 4 5 0 3 3 4 3 NOTE: Product

B2Bi Integration Serv. WebMethods NS 5 5 5 5 5 5 5 5 3 5 3 4 5 5 functionality isMQ Series family IBM/NEON NSHI 3 5 5 3 4 4 4 4 0 3 3 5 5 5 evolving.E*Gate STC 4 4 4 0 3 4 4 4 0 3 0 4 4 5Rendezvous TIBCO 3 5 4 4 4 5 4 4 3 3 3 5 5 5

H=HP UX, S=Sun Solaris, I=IBM AIX, N=MS Windows, 5 = strongest

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B2Bi: B2B commerce and EnterpriseApplication Integration (EAI)

B2Bi is based on the transformation and routingof XML documentsB2Bi patterns:

Direct Application IntegrationData ExchangeClosed Process IntegrationOpen Process Integration

Existing Frameworks:WebMethods B2Bi EAI frameworkMQSI (MQSeries Integrator)

See STP/T+1 in Sub-Topic 2/3 Presentations

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B2Bi Direct Application IntegrationArchitecture

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B2Bi Direct Application IntegrationRequirements

Ability to interact directly with applicationAPIsIntegration brokers with built-in support foradapters, transformations, and asynchronouscontent0based routingSame Integration Broker on both endsSecure transport, componentauthentification, and user authorizationsFederated security control

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Data Exchange B2BiArchitecture

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Data Exchange B2BiRequirements

Translation of data native to an applicationinto a common document format, andtransmission via a gatewayNo constraints on the presence ofIntegration BrokersB2B transactions enabled via a commondata exchange format

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Closed Process Integration B2BiArchitecture

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Closed Process Integration B2BiRequirements

Principal participant responsible formanaging processesOther participants are secondary, and do nothave visibility into the entire processRequires the introduction of businessprocess integration (BPI) services

B2Bi product offerings are beginning toincorporate BPI as an essential componentIn this case, B2Bi enables the integration oflogical business process elements expressed asactivities rather than data

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Open Process Integration B2BiArchitecture

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Open Process Integration B2BiRequirements

Introduces the notion of shared processesrather than operating from a centralizedmaster process manager modelEach participant is actively managingbusiness processes within its domainThe BPI layer must support fine-grainedcontrol of managed processes

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EAI Frameworks and XMLXML complements EAI technology

Powerful meta languageSimplicitySeparation of content and presentation formatCommon open standard

EAI Frameworks must address thelimitations of XML

Limited Semantics InterpretationLack of data transformation facilitiesInefficiencies of text-based documentsAbsence of component-based routing

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EAI Provides Data Transformations

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Efficiency: Binary Objects on the Wire

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Part V

Conclusion

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SummaryJava and XML technologies are available on connected devicesWhile bean-managed persistence provides the most portability, itgenerally fall short with respect to productivity.Container- managed persistence in EntityBeans provides the mostproductivityContainer-managed persistence typically provide the highest degreeof performance since, together, the code generation tools and thebean programmer can take advantage of container- specific mappingand caching technologyContainer-managed persistence currently falls short in the area ofportability

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Summary(continued)

XML complements application server technology by conveyingstructured data in a portable wayXML complements EAI technology, but future EAI framework stillneed to address XML’s limitationsWeb services platforms provide a shift from traditional enterprisedistributed object computing technology to P2P computing withsupport for pervasive devices, discovery and intelligent agentcapabilities

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Readings

ReadingsBuilding Application Servers: Part II, and IIIHandouts posted on the course web siteExplore Palm EnvironmentExplore EAI/B2Bi EnvironmentRead related white papers/documentation on the Palm, andEAI/B2Bi environments

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Project FrameworksProject Frameworks Setup (ongoing)

Apache Web Server (version 1.3.20, www.apache.org)Perl (version 5.x, www.perl.com), PHPMicrosoft IIS with COM+ and ASP (), ChiliSoftApache TomcatMacromedia JRunApache Cocoon 2/XSPVisibroker, OrbacusRMI-IIOPWindows 95/98/NT/2000 or Software AG’s EntireXWebLogic, WebSphere, JBoss, Enhydra, OpenEJBInprise AppServer, iPlanet.com iPlanet, Sybase EAServer, Oracle 9i, IONA iPortal, Xoology Concerto, AligoM-1, Advanced Network Systems WebIxGOAL Group OpenCCM, ExoLab.org OpenCCM, iCMG K2-CCM (C++), MICO/E (Eiffel ORB),JavaCCM, TAO Group, IONA iPortal (no CCM), Borland AppServer (no CCM), Sourceforge MI-3(“Mission Impossible 3”) and CIF projectsMicrosoft DNAApache’s XercesJ, XalanJ, XMLSpy, Antenna House XML Formatter, Apache’s FOP, X-smilesJWS, XMI Toolkit, IBM’s Web Service ToolkitPOSE, KVM for J2ME, NanoXMLIBM Alphaworks WSTK, XMI Toolkit, EJBMaker, WebMethods, etc.

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Assignment

Explore the references to Channel Independent, and EAI/B2BiApplication Server technologyHomework #6 due date is 11/19/01Homework #7: due date is 11/26/01Homework #8: due date is 12/10/01

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Next Session:Web Services Platforms (Part I)

XML-RPCSOAPUDDIWSDLC# and .Net