SAP Java World for ABAP Programmers

7/28/2019 SAP Java World for ABAP Programmers

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Session ID: CD102SAP Java World for

ABAP Programmers


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SAP AG 2005, SAP TechEd 05 / CD102 / 2

Contributing Speaker(s)

Ulrich KlingelsProduct Management, SAP AG


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SAPs Business Development Enhancements

Summary

Overview

Programming Model


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Summary

Overview

Programming Model


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Learning Objectives

As a result of this workshop, you willbe able to:

Get a Java and J2EE Overview

See similarities in the ABAP Paradigm

Understand the Java Server Architecture

See the enhanced features of the Java infrastructure

compared to the standard Java environment



Each is Unique But Comparable

Boston Subway London Underground


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Java Language J2EE and ABAP

Java is an object-oriented programming language

Source code is compiled into byte-code

Byte-code is interpreted by a Java Virtual Machine (JVM)

Java is platform independent

J2EE (Java 2 Platform Enterprise Edition)

Platform which simplifies and accelerates developing, deploying andmanaging n-tiered business applications using Java technologies

Java

language

Java

VMCom

piler ABAP

language

ABAP

VMCom

piler

JDK

J2EE

ABAP Runtime

Workbench (SE80)Developer Studio

Web Dynpro

ABAP

Environment

ABAPJava

Java Dictionary

JDI

.

( Web ) Dynpro

ABAP Dictionary

Transport Organizer

.



J2EE Architecture Overview

Web container

Manages the execution of JSP page and servlet components forJ2EE applications

EJB container

Manages the execution of enterprise beans for J2EE applications

J2EE Services

Foundation for implementation of multi-tier enterprise applications

J2EE Server

EJB Container

Client

Web Container

Database

J2EE

Services

JNDI JDBC

JMS .....

Servlets / JSPs EJBs



Local Development

File

System

Deploy

EJB

Container

Web

Container

Local Web AS Java

Save

J2EE Services

Deploy tocentral test

system

Local PC

Source files

Archive that contains binary f iles

Developer Workplace

SAP NetWeaver DeveloperStudio

Local Web AS Java

Development process

Develop Java sourcesin projects

Java Source stored onthe local file systemon your PC

Deploy projects to thelocal Java Engine

Test the projects local

Deploy projects to thecentral test system


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SAP NetWeaver Developer Studio

Extensible and open IDE basedon open source frameworkEclipse

Graphical and easy-to-use tools

to design, develop, deploy andcontinuously change missioncritical business applicationsin Java / J2EE

Web Services Tools forconnectivity based on openstandards

Web Dynpro Tools for model-

driven UI design

Design Time Repository Client

Java Dictionary for centralized

data type and data structuremanagement

Eclipse Plugin Framework

Java

Web

Services

Web

Dynpro

DTR

Client

J2EE

JavaDictionary

Integration Framework


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Summary

Overview

Programming Model

HTTP S l t d J S P (JSP)


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HTTP Servlet and JavaServer Pages (JSP)

Servlet is a Java class that

Handles HTTP communication

Runs on a Web server

Generates dynamic Web pages

Servlets can directly access resources like Enterprise

JavaBeans components, JDBC data sources

JSP Page is text file that hides HTTP complexity from

programmer

HTTP RequestServlet

generateJSP

HTTP Response

Web Container EJB Container

Browser

Servlet ~ HTTP handler (IF_HTTP_Extension)

Java ~ ABAP

JSP ~ Layout of BSP page

E t i J B D fi iti


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Enterprise JavaBeans Definition

An Enterprise Bean is a server-side component that encapsulates

the business logic of an application

EJBs always execute within an EJB container, which provides

system services to EJBs

These services include transaction management, persistence,

pooling, clustering and other infrastructure

J2EE Server

EJB Container

EJB

EJB

EJB

EJB

EJB

EJBEJB

T f E t i J B


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Types of Enterprise JavaBeans

EnterpriseJava Bean

Message-driven Bean

Session Bean Entity Bean

Stateless

Session BeanStateful

Session Bean

Container-

managedpersistence

Bean-

managedPersistence

Related to the usersession

Session bean is not

persistent

Handles the persistencein a object-oriented

manner

Represent a business

object

Message based

Receive

asynchronous

JMS messages

Session Beans


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Session Beans

A session EJB represents a single

client inside the application server

A client accesses the application byinvoking the session bean's methods

Shields the client from complexity byexecuting business tasks inside theserver

A session bean is not shared at acertain point of t ime: it may have just

one client

Session beans are divided into twobasic types:

Stateless

Not dedicated to one client pooledamongst a number of clients. Be awarethat instance is reused for clients(initialize attributes)

Stateful

Is created for a specif ic cl ient and notused (reused) by any others

J2EE Server

EJB Container

Client

Session bean ~ function group / ABAP class

State ~ global memory of funct ion group

Session bean methods ~ function modules/ ABAP method

Java ~ ABAP

Client Client

Stateful

SessionBean

StatelessSessionBean

Entity Bean Persistence


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Entity Bean Persistence

Entity EJB represents a business object(e.g. customers, orders and products)

Two types

Bean-Managed Beans (BMP)

Container managed Beans (CMP)

The persistent storage mechanism isa relational database

Typically, each enti ty bean has an underlyingtable in a relational database, and each instanceof the bean corresponds to a row in that table

Entity beans differ from session beansin several ways

Are persistent (dedicated load/store methods)

Allow shared access

Have primary keys

May participate in relationships with other entity beans

J2EE Server

EJBContainer

Session Bean

Entity Bean

Database

Message Driven Beans


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J2EE Server

EJB

Container

Message-Driven Beans

MDBs were created to receive

asynchronous JMS messages

JMS supports Publish-and-

Subscribe (Topic) and Point-To-

Point (Queue)

The container handles much

of the setup required for JMS

queues and topics

The container sends all

messages to the interested MDB

MDB are statless

JMSQueue Topic

Queue

Sender BQueue

Sender A

Topic

Publisher A

MDB

B

MDB

A

MDB

C

MDBC

No interfaces (Home/Component)

Can consume and process

messages concurrently

ejbejb --j2eej2ee--engine.xmlengine.xml

Bean

configuration

provider.xmlprovider.xml

EJB Asynchronous (queue) ~

Call Function in update task

Java ~ ABAP

A Deployment Descriptor is a File that


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A Deployment Descriptor is a File that .

Project

Deployment

Descriptors

EntityBean

SessionBean

CustomerServicesBean

com.sap.fi.ejb.CustomerHome

......

com.sap.fi.ejb.CustomerBean

Stateless

Container

......

CustomerEntityBean

Container

.......

Defines EJB structural information, such as

EJB name, class, home and remote interfaces

Bean type (session or entity)

Defines application assembly information, such as

Container transaction attributes

Method permissions

Security roles

Purpose

customizing the program

ejbejb--jar.xmljar.xml

Deployment descriptor ~ program attributes

Java ~ ABAP

Project Types


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Project Types

SA

PWebAp

plicationS

erver

MyWebModuleProject

Web

MyEJBModuleProject

EJB

EAREAR

MyDictionaryProject

Table

SDA

WAR

Deploy

MySessionBean

MyEntityBean

HelperClassDeployment

Descriptors

MyJSP

MyServletDeployment

Descriptors

EJB-

JAR

MyEnterpriseApplProject

MyDataSourceAliasDeployment

Desc

riptors

SDA

Deploy

MyDatabaseTableMyDatabaseTable

MyWebDynproProject

WebD

ynpro

Deploy

MyWDApplicationMyWDApplication

WAR

EJB-

JAR

EAREAR


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Summary

Overview

Programming Model

SAP provides more than J2EE!


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SAP provides more than J2EE!

Software

Life Cycle

Java

Dictionary

To adopt J2EE for large business applications, SAP

extended the programming model

integrated existing non-J2EE open standards

provides a highly productive development infrastructure

Presentation Layer

Business Layer

Busine

ssApplicatio

n

Integration

Layer

Servlet JSP

EJB

Persistence

JDBC Open SQL

Web Dynpro

Web

Services

SQLJ

Web Dynpro for Java (=ABAP)P f i l B b d U I t f


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Model-driven user interface development

Higher abstraction level that server pageapproaches (JSP, BSP)

Frontend / backend separationis straightforward

Few coding, lots of design

Graphical tools for building UIs basedon the common meta-model

Mix & match static (declarative)and dynamic (programmatic) parts

Central implementation of user interface standards

Reuse of common structures

Support for pattern-based UI development

508 Accessibility

Adobe Forms integration

Standardized cl ient technologyBrowser, Mobile devices, Smart clients, ...

Professional Browser-based User Interface

Web Dynpro Java ~ Web Dynpro ABAP

Web Services based on Open Standards


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eb Se ces based o Ope Sta da ds

StandardInterfaces

Virtual Interface

BusinessApplication

IDOC

BAPI

RFC

EJB

JavaClass

XIServer

Proxy

SAP Web Application Server

UDDIUDDI

Registry

WS

Client WSDL

SOAP

Development Environment

Web Service Consumer

Web serviceProxy

Web service ClientApplication

Web Service Runtime

Web Service Provider

SOAP

Java Dictionary (JDIC) A Light Weight Data (ABAP) Dictionary


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A Light Weight Data (ABAP) Dictionary

Create elementary types, structures, and database tables

Supported

DB index

Table buffer

Global namespace (Name Server)

Data types

Benefits

Enables database independency

SQLJ is based on JDIC

Included in Web Dynpro

Open SQL features

Not supported

Foreign keys

Same data types as ABAP

No Domain concept

No transport of content

Java Dictionary ~ Data Dictionary

Java ~ ABAP

Open SQL for JavaLarge Scale Persistency Framework


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Large-Scale Persistency Framework

Open SQL Engine

^

Open SQL / JDBC

Open SQL / SQLJ

JDO

EJB (CMP)

SQL Trace

Statement Cache

Table Buffer

Table Catalog

Native SQL

/ JDBC

Vendor A JDBC Vendor B JDBC. . .

Relational Persistence (SQL) Object Relational PersistenceDatabase

independency

Open SQL

Development support

Syntax check during

implantation

Performance

enhancements

Server side Table Buffer

SQL Statement Cache

SQL Trace

Open SQL Engine

Java ~ ABAP

Open SQL for Java

~ Open SQL for ABAP Database BDatabase A

Overview: Java Development Infrastructure (JDI)


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p ( )

< Local Installation on Developers PC >

SAP NetWeaver Developer Studio

Run

Time

JavaSystems

Deploy

Local File

System

Component

Model

Local J2EE

Engine

Component

Build Service

(CBS)

Design TimeRepository

(DTR)

Name ServerCh

angeManagementServic

e

(CM

S)

System LandscapeDirectory (SLD)Java ~ ABAP

JDI ~

Transport Organizer

ABAP and Java together


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Presentation Layer

Database Instance

Java Schema

ABAP Schema

EJB

Open

SQL

Web

Dynpro

Business Layer

Persistence

FM /

BAPI

Open

SQL

Web

Dynpro

JCo

ABAPJava recommendedConnectivity between

ABAP and Java

NOT recommendedConnectivity between

ABAP and Java

Web Service

consumer

Web Service

provider

Any Web Service

consumer can use

any Web Service

provider


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Summary

Overview

Programming Model

Summary


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The Web AS is one platform supporting two technology

stacks

In addition to J2EE SAP provides tools and technologies

developing for professional business applications based

on Java

SAP provide a sophisticated Java infrastructure for

development and deployment

ABAP and Java resides together

ABAP or Java it is your decision

Further Information


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Public Webwww.sap.com

NetWeaver Developers Guide: www.sdn.sap.com/sdn/developersguide.sdn

SAP Developer Network: www.sdn.sap.comWeb Application Server

SAP Customer Services Network: www.sap.com/services/http://java.sun.com/docs/overviews/java/java-overview-1.html

http://java.sun.com/j2ee/tutorial/

Related SAP Education Training Opportunitieshttp://www.sap.com/education/

Questions?


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Q&A


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