Mastering SAP ABAP: A complete guide to developing fast, durable, and maintainable ABAP programs in SAP

Mastering SAP ABAP

A complete guide to developing fast, durable, and maintainable ABAP programs in SAP

Paweł Grześkowiak

Wojciech Ciesielski

Wojciech Ćwik

BIRMINGHAM - MUMBAI

Mastering SAP ABAP

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I would like to dedicate this book to my fiancée, Natalia, for her support

and unlimited level of patience.

– Paweł Grześkowiak

To my wife, Anna, for being my loving partner throughout our joint life journey.

To my mother, Danuta, and to the memory of my father, Bogumił, for their sacrifices and

for exemplifying the power of determination, love, support, and inspiration;

and to my sister, Ewelina, for her smile and for not giving up.

– Wojciech Ciesielski

I dedicate this book to my wife, Jagoda, for her love, faith, support, and for being

an invaluable life companion.

– Wojciech Ćwik

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Contributors

About the authors

Paweł Grześkowiak has been passionate about programming from his early years, and since 2012 he has been a SAP technical consultant—mainly in the ABAP area. He has expertise in boosting implementations in the rail transport industry, the chemical industry, media, government administration, the wood industry, and banking. Currently, he designs extensions to SAP S4/HANA systems in ABAP and Java. He is an active member of the SAP community and a three-time SAP Inside Track conference organizer.

I would like to thank all my colleagues from Capgemini who helped make this book better: Krzysztof Bulanowski, Daniel Iwanowski, Bogdan Brzozowski, Mateusz Skadorwa, Marcin Maciejewski, Piotr Roszak, and Marcin Bielecki. Special thanks to Anna Wilk for checking all the examples carefully and for her brilliant review. Last but not least, many thanks to my Capgemini mentor, Paweł Gaura, for his support in my career and development.

Wojciech Ciesielski graduated from the Wroclaw University of Technology with an Engineering degree in Automation and  Robotics, and he has a master's degree in Management in WSB Universities. Since then, he has been tightly connected with the SAP environment, working as an ABAP consultant. He has several years of business background in ABAP development and the use of modern technologies in business. He is experienced in working with ERP and CRM systems and integrating them with third-party solutions—from single companies to multinational corporations. He is a co-creator of innovative solutions delivered to the wide international audience of SAP events. He is currently focused on new technologies and solutions in the SAP portfolio: SAP Cloud Platform, Internet of Things, and artificial intelligence; but he is also increasing his expertise in development with other languages.

Wojciech Ćwik has been a certified ABAP consultant for several years, with a specialty in mobile solutions, especially in creating interfaces between SAP and frontend solutions from Fiori and third-party platforms; he also enjoys creating architectures in SAP ERP ecosystems. He is a co-originator of an unconventional system linking new solutions from the SAP portfolio such as IoT, SAP Cloud, and SAP blockchain services.

About the reviewer

Dariusz Pacynko graduated from Wroclaw University of Technology with an MSc degree in Optical Engineering. Since then, he has been tightly connected with the SAP environment, working as an ABAP consultant. He has multiple certifications, such as ABAP with SAP Netweaver 7.40 Development Associate, and several years of business background including experience with ABAP development, OData services, and SAPUI5 applications. He is experienced in working with ERP and CRM systems, integrating them with third-party solutions, and opening them to the mobile philosophy. He is a co-creator of innovative solutions delivered to the wide international audience of SAP events. He is currently focused on the new technologies and solutions in the SAP portfolio, such as SAP Cloud and IoT, but he is also increasing his expertise in Fiori development.

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Table of Contents

Title Page

Copyright and Credits

Mastering SAP ABAP

Dedication

About Packt

Why subscribe?

Packt.com

Contributors

About the authors

About the reviewer

Packt is searching for authors like you

Preface

Who this book is for

What this book covers

To get the most out of this book

Download the example code files

Download the color images

Code in action

Conventions used

Get in touch

Reviews

Creating Custom Code

Technical requirements

Making changes

Design thinking

BDUF/LDUF

Designing for quality and use

Designing the UI

Designing services

Designing the business logic

Designing the database

Agile principles

DevOps

Continuous delivery

Summary

Questions

The Basic Structure of ABAP

Technical requirements

The Data Dictionary

Domains

Data elements

Structures

Search helps

Table types

Databases

Data declaration

Field symbol

Summary

Questions 

Database Access in ABAP

Technical requirements

Starting with OpenSQL

Basics

Possibilities with SELECT - the first part of the SQL statement

Possibilities with INTO - the third part of the SQL statement

The WHERE condition

How to see data selected from a database

More advanced possibilities in OpenSQL

WHERE conditions

Dynamic SELECT in WHERE

SINGLE FOR UPDATE

GROUP BY

ORDER BY

UP TO and ROWS

SELECT and ENDSELECT

FOR ALL ENTRIES

Subqueries

Reading data from several tables

Identifying and saving the changes

Creating datasets

Updating datasets

Deleting datasets

The optimization of reading big datasets

The new SQL syntax

Inline declaration

SQL expression

Using the SQL Trace tool for performance analysis

Summary

Questions

Import and Export to Document Formats

Technical requirements

Client-side file processing

Reading files from the local PC using gui_upload

Writing files to the local PC using gui_download

Server-side file processing

Basic transactions related to server-side files

Writing files to the application server

Reading files from the application server

Working with Microsoft Office files

Reading data from Microsoft Excel

Saving a table to a Microsoft Excel file

Working with Microsoft Word

Using DOI to integrate Microsoft Office applications into ABAP reports

Summary

Questions

Further reading

Exposing Data to Print Forms

Technical requirements

Introduction to printouts in SAP

SAPScript - the great-grandfather of all printouts

Creating our first SmartForm

Adobe Forms

Creating our first Adobe Form

Summary

Questions

Further reading

ABAP and XML

Technical requirements

Using the CL_XML_DOCUMENT class for XML

Reading and parsing XML files to ABAP

Changing XML data

Simple transformations in ABAP

Serialization using ST

Deserialization using ST

sXML library for XML and JSON

Converting XML to JSON

Summary

Questions

Further reading

Building User Interfaces

Technical requirements

Classic DynPro

Screen painter

Selection screens

More advanced options of the selection screen

Checkbox

Radiobutton

Blocks in selection screens

Selection screen event model

ALV

Basics

Advanced capabilities of ALV sand screens

Zebra

Coloring

Event of an ALV, exemplified by a button click 

Icons in the ALV

Text fields and translations

Input/output field

Radiobuttons and checkbox

Button

Dynamic display possibilities for individual elements and groups

Summary

Questions

Creating Stunning UI5 Interfaces

Technical requirements

Development tools

Layouts and floorplans

SAP Fiori elements

The analytical list page

The list report

The object page

The overview page

The worklist

Layouts

Floorplans

The initial page floorplan

The multi-instance floorplan

The wizard floorplan

Basic templates

The SAPUI5 library

Control documentation page and inheritance

Contextual info

Overview

Constructor

Properties

Associations

Aggregations

Events

Methods

Inheritance

Main controls

Custom controls

Creating our first mobile app

Application and project structure

index.html

The standard variant

The content delivery network

The miscellaneous variants

Component.js

manifest.json

Views and controllers

MainView.view.xml

SearchView.view.xml

SearchView.controller.js

i18n.properties

Testing SAPUI5 apps

Mock Server

Unit tests

Integration tests

Summary

Questions

Further reading

Business Object Processing Framework

Technical requirements

An introduction to BOPF

Transaction

Nodes and entities

First BOPF example 

Creating the object

Displaying an object

Summary

Questions

Further reading

Modification and Customization Techniques

Technical requirements

Legacy ways of changing the standard

Customer Exits

Using BTE to extend FI functionality

Modifications

FQEVENTS

Appends

Classical BAdl

Enhancement framework and its components

Enhancement sections and Enhancement points

Implicit enhancements

Summary

Questions

Further reading

Handling Exceptions in ABAP

Technical requirements

Classic exception handling

Handling

Raising

Class-based exceptions

Handling

Raising

Assertions

Building a checkpoint group

Defining assertions

Using assertions

Runtime errors

ABAP dump analysis tool

Error log

System environment

User View

ABAP developer View

BASIS developer View

Summary

Questions

Testing ABAP programs

Technical requirements

Testing the quality of code

Static testing with Code Inspector and ABAP Test Cockpit

Testing and troubleshooting

ABAP Memory Inspector

Advanced ABAP debugger techniques

Testing with eCATT

Summary

Questions

Further reading

Advanced Techniques in ABAP Objects

Technical requirements

Global versus local classes

Creating a local class

Creating a global class

The static method versus the instance method

Nested classes

A class as an attribute of the class

Inheritance

Interfaces

The event concept

ABAP Objects design patterns

Prototype - creation pattern

Singleton - creation pattern

Facade - structural pattern

Decorator - structural pattern

Observer - behavioral pattern

Strategy - behavioral pattern

Summary

Questions

Integrating SAP with Third-Party Systems

Technical requirements

IDoc 

IDoc overview

The construction of IDoc

The EDI system

ALE

Differentiating ALE from EDI

BAPI

Implementing BAPI

SAP Gateway

Deployment variants

Embedded

Hub

Hub (with development)

Main tools

Gateway Service Maintenance

Gateway Client

Error Log

Gateway Service Builder

The OData protocol

Characteristics

The service definition

Developing our first OData application

Design time

Providing data

Summary

Questions

The Background Processing of ABAP Programs

Technical requirements

Background processing in SAP

Background remote function call

Scheduling background jobs

Creating a background job

Recording batch input sessions

Summary

Questions

Performance and Optimization of ABAP Code

Technical requirements

Ways of measuring ABAP programs performance

ABAP runtime analysis

ABAP trace analysis

ABAP SAT transactions

Best practice techniques

Summary

Questions

Assessments

Answers

Chapter 1 - Creating Custom Code

Chapter 2 - The Basic Structures of ABAP

Chapter 3 - Database Access in ABAP

Chapter 4 - Import and Export to Document Formats

Chapter 5 - Exposing Data to Print Forms

Chapter 6 - ABAP and XML

Chapter 7 - Building User Interfaces

Chapter 8 - Creating Stunning UI5 Interfaces

Chapter 9 - Business Object Processing Framework

Chapter 10 - Modification and Customization Techniques

Chapter 11 - Handling Exceptions in ABAP

Chapter 12 - Testing ABAP Programs

Chapter 13 - Advanced Techniques in ABAP Objects

Chapter 14 - Integrating SAP with Third-Party Systems

Chapter 15 - Background Processing of ABAP Programs

Chapter 16 - Performance and Optimization of ABAP Code

Additional tutorials

Creating a report from the template

Uploading graphics to SE78

Another Book You May Enjoy

Leave a review - let other readers know what you think

Preface

Advanced Business Application Programming (ABAP) is an established and complex programming language in the IT industry. This book will be your guide to becoming an industry expert in Systems, Applications, Products (SAP) ABAP. You will learn how to write custom code that is suited for the latest version of SAP ABAP as well as the older versions of SAP. By exploring practical examples, you will learn how to make user-friendly interfaces and will uncover various ways to optimize your ABAP code.

Who this book is for

This book is for developers who want to learn and use ABAP skills in order to become an industry expert. Familiarity with object-oriented programming concepts is expected.

What this book covers

Chapter 1, Creating Custom Code, focuses on available actions for changing SAP systems within the modern and ever-changing SAP wold.

Chapter 2, The Basic Structure of ABAP, focuses on the distinction between ABAP and modern programming languages.

Chapter 3, Database Access in ABAP, describes how to extract data from a database in ABAP.

Chapter 4, Import and Export to Document Formats, focuses on the toolset the ABAP developer has for importing and exporting data to/from different environments.

Chapter 5, Exposing Data to Print Forms, explains how to represent extracted data in a user-friendly print form, how to make it clearly readable, and how to make its maintenance less time-consuming.

Chapter 6, ABAP and XML, deals with the different tools ABAP has for XML manipulation, their performance features, and what real-life scenarios they are intended for.

Chapter 7, Building User Interfaces, focuses on how to build classical Dynpro with the help of ABAP tools. It explains what screen types exist and how they are interconnected with each other, what GUI controls ABAP developers have in their toolset, and which of them are recommended and which are not. It also describes ABAP List Viewer (ALV) controls and the ALV component model.

Chapter 8, Creating Stunning UI5 Interfaces, places UI5 in the family of SAP interfaces and explains how to use it in the most efficient way.

Chapter 9, Business Object Processing Framework, gives an overview of Business Object Processing Framework (BOPF) and explains why it is important in SAP environments for the acceleration of development, easier maintenance, and supportability.

Chapter 10, Modification and Customization Techniques, describes the customization techniques across SAP modules, explaining which techniques are recommended to use and which are outdated.

Chapter 11, Handling Exceptions in ABAP, covers testing exceptions in ABAP, the types of exception that have existed from the beginning, and the types we have now. It also recommends the proper way of handling exceptions, explaining in which situations it is strongly required, and those in which it is not recommended.

Chapter 12, Testing ABAP Programs, explains how to test ABAP programs for performance without sacrificing the clarity of ABAP code and how to use the ABAP Debugger correctly to find bottlenecks and speed up ABAP programs.

Chapter 13, Advanced Techniques in ABAP Objects, deals with the advantages ABAP objects bring to the development process. 

Chapter 14, Integrating SAP with Third-Party Systems, focuses on how to build a stable and error-prone connection of a SAP system with non-SAP software.

Chapter 15, Background Processing of ABAP Programs, reveals all the ins and outs of background data processing in SAP that you may face, and the approaches that are used to handle with them.

Chapter 16, Performance and Optimization of ABAP, provides a thorough review of the available ABAP toolset for testing the performance of ABAP apps and tuning their execution. It also gives some best practice tips and tricks of internal ABAP statements and focuses on tracing and tuning OpenSQL selections.

To get the most out of this book

The reader should know the basics of programming, as well as the basics of SQL and operations on databases. Basic knowledge of business processes will also be helpful. This book also deals with the subject of UI5; therefore, it is worth the reader knowing the basics of JavaScript. 

To create code in ABAP, the readers also need access to SAP systems with the developer key. 

To create applications in UI5, the readers should create a trial account in the SAP Cloud Platform. The SAP Web IDE Full-Stack developer environment is available there. The programming environment allows you to create and extend SAP applications on a full stack for browsers and mobile devices.

Download the example code files

You can download the example code files for this book from your account at www.packt.com. If you purchased this book elsewhere, you can visit www.packt.com/support and register to have the files emailed directly to you.

You can download the code files by following these steps:

Log in or register at www.packt.com.

Select the SUPPORT tab.

Click on Code Downloads & Errata.

Enter the name of the book in the Search box and follow the onscreen instructions.

Once the file is downloaded, please make sure that you unzip or extract the folder using the latest version of:

WinRAR/7-Zip for Windows

Zipeg/iZip/UnRarX for Mac

7-Zip/PeaZip for Linux

The code bundle for the book is also hosted on GitHub at https://github.com/PacktPublishing/Mastering-SAP-ABAP. In case there's an update to the code, it will be updated on the existing GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

Download the color images

We also provide a PDF file that has color images of the screenshots/diagrams used in this book. You can download it here: https://www.packtpub.com/sites/default/files/downloads/9781787288942_ColorImages.pdf.

Code in action

Visit the following link to check out videos of the code being run: http://bit.ly/2M4ILyK.

Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in the text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: In the Details window, create lines %C1 and %C2 with the values that are shown in the following screenshot.

A block of code is set as follows:

    id=sap-ui-bootstrap

    src=resources/sap-ui-core.js

    data-sap-ui-libs=sap.m

    data-sap-ui-theme=sap_belize>

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

data-sap-ui-bindingSyntaxt=complex

data-sap-ui-resourceroots='{ my.namespace:./ }'

Any command-line input or output is written as follows:

$ mkdir css

$ cd css

Bold: Indicates a new term, an important word, or words that you see onscreen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: Select System info from the Administration panel.

Warnings or important notes appear like this.

Tips and tricks appear like this.

Get in touch

Feedback from our readers is always welcome.

General feedback: If you have questions about any aspect of this book, mention the book title in the subject of your message and email us at [email protected].

Errata: Although we have taken every care to ensure the accuracy of our content, mistakes do happen. If you have found a mistake in this book, we would be grateful if you would report this to us. Please visit www.packt.com/submit-errata, selecting your book, clicking on the Errata Submission Form link, and entering the details.

Piracy: If you come across any illegal copies of our works in any form on the Internet, we would be grateful if you would provide us with the location address or website name. Please contact us at [email protected] with a link to the material.

If you are interested in becoming an author: If there is a topic that you have expertise in and you are interested in either writing or contributing to a book, please visit authors.packtpub.com.

Reviews

Please leave a review. Once you have read and used this book, why not leave a review on the site that you purchased it from? Potential readers can then see and use your unbiased opinion to make purchase decisions, we at Packt can understand what you think about our products, and our authors can see your feedback on their book. Thank you!

For more information about Packt, please visit packt.com.

Creating Custom Code

The chapter is an introduction to the Systems, Applications, Products (SAP) system. You will learn how to organize their daily work, how to act within SAP systems, how to add custom code, and how to change software features of SAP systems. This chapter presents modern techniques of cooperation within a company. Basic knowledge of these issues is required to work with the SAP system. This chapter is an introduction to the more complex and difficult topics contained in this book.

The following topics will be covered in this chapter: 

Making changes

Design thinking

Big Design Up Front/Little Design Up Front (BDUF/LDUF)

Designing for quality and use

Designing the User Interface (UI)

Designing the services

Designing the business logic

Designing the database

Agile principles

DevOps

Continuous Delivery

Technical requirements

This chapter does not have complex technical requirements. To check the solutions and examples, it is worth having user access to the SAP system. Other information (for example, agile designing the UI) can be better understood by IT employees. However, it is worthwhile for everyone who's interested in working with SAP systems to read the information contained in this chapter.

All the code used in this chapter can be downloaded from the following GitHub link: https://github.com/PacktPublishing/Mastering-SAP-ABAP/tree/master/Chapter01.

Making changes

There are several ways in SAP to make changes. Some of them are configuration changes, and some are purely programmatical changes.

SAP systems can be enhanced in five ways:

Customizing: Specific business and functional process configuration according to the implementation guide. The need to make these changes is predicted by SAP and the procedure of implementation has been developed.

Personalization: Setting up global attributes to display certain fields (such as default values or switching off the display of a field).

Modification: These are changes SAP Repository objects make at the client side. SAP also can deliver a new version of those objects, and customers need to reflect these changes in the system. Before version 4.0B, customers needed to make this adjustment manually using upgrade utilities. From 4.5A, customers can use the Modification Assistant to automate this procedure.

Enhancement: Creating a repository object inside a standard SAP program. More details about enhancement will be in Chapter 10, Modification and Customization Techniques.

Custom development: This means creating objects that are unique to the client repository, which is created in the specified namespace, such as Y* or Z*, for all new objects.

In your daily work as an ABAP programmer, your most common work is creating custom developments and enhancements. Since we have a chapter on enhancements, we will focus here on custom development.

In custom development, we can create a custom program and dictionary elements. There will be more about creating dictionary elements in Chapter 2, The Basic Structure of ABAP.

As an example, we will show you how to create one of the most basic programs: Hello World.

In the first step, we need to open one of the most commonly used transactions in our daily work—SE80. This transaction is called Object Navigator, and is a transaction where we can create, change, and delete most ABAP objects.

The main window for the SE80 transaction looks like this:

First, to open the SE80 transaction, we need to put the name of the transaction in the search box, as shown in the following screenshot:

 Press enter, or click on .

After opening a transaction, we need to choose the Program option in the drop-down list on the left and enter the name Z_HELLO_WORLD in the window, as shown in the following example, and press Enter:

In the next window, choose Yes:

Confirm the name of a new program in the next window. Click on  or press Enter:

In the next window, define the attributes of the program, and now press Enter or click on  :

After this, choose a package. We need to create a program as a local object, so click on :

After this, we get a window like this:

Now change the mode to Change by clicking on the   icon or pressing Ctrl + F1. The background color of the window with the code will change to white. Now we put the code there.

To print Hello world on the screen, we just need to add this:

WRITE 'Hello World'.

Remember! All ABAP custom programs needs REPORT NAME_OF_PROGRAM at the beginning.

The program looks similar to the following screenshot:

The program now needs to be activated. To activate it, click on   or press Ctrl + F3. When an object has been activated, a message will be shown:  .

To execute the program, click on  or press F8:

The result of the program is shown in the preceding screenshot.

Design thinking

Design thinking is a method of creative problem-solving. This method is designed to deliver innovative solutions by using a specific work method. The motto of this method is doing, not talking, so going over every detail of the project is changed into a multi stage division of tasks in order to extend and refine subsequent tasks.

The process of design thinking is divided into five steps:

Empathy: All of the new solutions are created for people. Therefore, the needs of a given group of people should be known, and this is why empathy is the starting point of all projects created by design thinking. To find the optimal solution, we need to see how this solution will help the common user.

Define the problem: In this stage, we need to define the exact problem to solve. We need to remember not to define problems in too narrow or too wide a range so that the solution will not be limited by rigid frames.

Ideas: This stage consists of creating as many ideas as possible for solutions relating to the previously defined problem. In this step, a brainstorm is very useful. The important thing is not to stick to your own ideas, and not to judge others. These sessions should be ended by choosing a concrete solution, which will be picked from the previously selected ideas.

Prototypes: Creating the prototypes is an indispensable step. Building prototypes should not be a very complicated process. The most important thing is to make a preliminary visualization of the idea, because only in that way can the idea be tested naturally. Every subsequent prototype should be created by thinking of the user and answering concrete questions.

Tests: This step is extremely important. In this step, the product is tested in a real environment, so you can check that it functions correctly. Every prototype can be evaluated by the group (for example, the project group), and the best one will be chosen for further improvements. Testing should be repeated until a satisfactory result is obtained.