SAP Interface Programming

Introduction ... 11

1. ... The Basics of R/3 System Architecture ... 15
... 1.1. The Application Server ... 16
... 1.2. The Dialog Process ... 18
... 1.3. The Update Task ... 20
... 1.4. The Enqueue Process ... 21
... 1.5. The Gateway Server ... 23
... 1.6. Distributed Load Systems and the Message Server ... 26
... 1.7. The RFC Interface Within the R/3 System ... 28

2. The Basics of the ABAP Programming Language ... 31
... 2.1. The ABAP Development Environment ... 32
... 2.2. Creating Database Tables ... 36
... 2.3. A Simple Program ... 44
... 2.4. ABAP Data Types and Variable Declaration ... 48
... 2.5. Elementary Programming Statements in ABAP ... 52
... 2.6. Creating Function Modules ... 61
... 2.7. Coding Conventions in This Book ... 68

3. Introduction to Programming with the RFC API 71
... 3.1. The Task for the First Example ... 72
... 3.2. Programming the SAP Function Modules ... 73
... 3.3. Programming the Client ... 75
... 3.4. Frequent Errors on the Client Side ... 91
... 3.5. Overview of the Functions and Structures Used ... 93
... 3.6. From an RFC Function Call to the Function Module ... 93
... 3.7. Programming the External Server ... 96
... 3.8. Frequent Errors on the Server Side ... 115
... 3.9. Functions Used ... 116

4. The Basics of RFC Programming ... 117
... 4.1. Type Mapping and Data Aggregates ... 117
... 4.2. Working with Structures ... 130
... 4.3. Working with Internal Tables ... 136
... 4.4. The Message Loop ... 148
... 4.5. Alternatives for Logging on to an R/3 System ... 151

5. Troubleshooting ... 157
... 5.1. The ABAP Debugger ... 157
... 5.2. The BREAK Statement ... 160
... 5.3. The Gateway Monitor ... 161
... 5.4. The RFC Trace ... 162
... 5.5. The RFC Generator ... 169
... 5.6. SAP Test Programs ... 175

6. Advanced Techniques ... 181
... 6.1. Return Calls from the Server ... 181
... 6.2. Automatic Creation of a Structure Description ... 190
... 6.3. Transactional Remote Function Calls ... 196
... 6.4. Queue RFCs ... 211
... 6.5. Error Messages from an External Server ... 227
... 6.6. Parallel Processing ... 233

7. The Business Object ... 253
... 7.1. Business Object-Close to the Object ... 253
... 7.2. Structure of the Business Object ... 256
... 7.3. The Structure of the Business Object Builder ... 261
... 7.4. Creating the Object Key ... 264
... 7.5. Methods of the Business Object ... 266
... 7.6. Object Release and the Business Object Repository ... 276
... 7.7. Guidelines for Developing API Methods ... 278
... 7.8. Possibilities for Activation ... 280

8. Calling BAPIs from Clients ... 283
... 8.1. What Are COM and ActiveX? ... 283
... 8.2. "What Is Your Name?" or an Introduction to the Use of ActiveX Controls ... 287
... 8.3. Naming Conventions During Programming ... 297
... 8.4. Wrapping the BAPI Proxy Object ... 298
... 8.5. A Better Method for Setting Up a Connection to the R/3 System ... 301
... 8.6. Concepts for Creating Data Aggregates ... 310
... 8.7. The SAP TableFactory Control in Detail ... 313
... 8.8. Administering Structures with the SAP TableFactory Control ... 314
... 8.9. Working with Tables ... 318
... 8.10. Visualization of the Table Contents ... 328

9. SAP and Java ... 349
... 9.1. The SAP Java Connector ... 351
... 9.2. Using the JCo ... 354
... 9.3. The Future of the SAP Java Interface ... 368

A Sources and Further Reading ... 371
B About the Authors ... 373
Index ... 375