The ABAP Developer´s Guide to Java

1 Introduction ... 11

2 Technology Overview ... 17
... 2.1 Enterprise Services Architecture ... 18
... 2.2 SAP NetWeaver ... 19
... 2.3 System Architecture of the SAP Web Application Server ... 21
... 2.4 Major Components of the SAP Web Application Server ... 24
... 2.5 Database Integration ... 30
... 2.6 Web Services ... 33
... 2.7 Frontends ... 36
... 2.8 Authorization System ... 46
... 2.9 Versioning and Transport System ... 54
... 2.10 Availability, Performance, Scalability ... 59
... 2.11 Integration Options for ABAP and J2EE ... 60

3 The "ResMan" Example Project ... 63
... 3.1 Prerequisites ... 63
... 3.2 The Data Model ... 65
... 3.3 Technical Implementation of the Prerequisites ... 69

4 The Programming Languages of the SAP Web Application Server ... 71
... 4.1 ABAP and ABAP Objects ... 71
... 4.2 Java ... 90

5 Development Tools and Objects ... 137
... 5.1 ABAP ... 137
... 5.2 J2EE ... 166

6 Application Layers ... 255
... 6.1 Retrieval Logic and Persistence ... 255
... 6.2 Middleware: Connectivity Between Applications ... 297
... 6.3 Business Logic ... 344
... 6.4 Presentation Logic ... 361

7 Application Design ... 421
... 7.1 A Typical Problem ... 421
... 7.2 Design Patterns ... 422
... 7.3 Developing an ABAP Web Application ... 436
... 7.4 Developing a J2EE Web Application ... 438

8 Performance Aspects ... 441
... 8.1 Performance under ABAP ... 441
... 8.2 Performance under Java ... 445

9 Outlook ... 455

A Glossary ... 459

B Sources and Further Reading ... 479

C About the Authors ... 481