ABAP Programming Guidelines PDF 14: How to Maximize Performance, Readability, and Stability in Your ABAP Programs
ABAP (Advanced Business Application Programming) is a high-level programming language developed by SAP for creating business applications. It is widely used for developing SAP applications that run on SAP NetWeaver Application Server (AS) ABAP platform.
Official Abap Programming Guidelines Pdf 14
ABAP programming is not only about writing code, but also about following certain guidelines and standards that ensure the quality, readability, maintainability, and performance of the code. These guidelines also help to avoid common errors and bugs, as well as to facilitate collaboration and communication among developers.
In this article, we will explore the official ABAP programming guidelines PDF 14, which is a document that provides a comprehensive and consistent set of rules and recommendations for ABAP programming. The document covers various aspects of ABAP programming, such as general rules, ABAP-specific rules, structure and style, architecture, and robustness. We will also provide some examples and tips on how to apply these guidelines in practice.
The general rules for ABAP programming are the basic principles that apply to any programming language. They include naming conventions, comments, indentation, and formatting. These rules help to make the code more consistent, clear, and understandable.
Naming conventions are the rules for naming ABAP objects, such as classes, methods, variables, constants, etc. Naming conventions help to avoid name conflicts, to indicate the purpose and scope of the objects, and to make the code more readable.
Some of the naming conventions for ABAP objects are:
Use descriptive and meaningful names that reflect the functionality and role of the objects.
Use camel case for names that consist of multiple words, such as myVariable, myMethod, myClass, etc.
Use prefixes or suffixes to indicate the type or category of the objects, such as g_ for global variables, c_ for constants, i_ for importing parameters, e_ for exporting parameters, etc.
Use uppercase letters for constants and literals, such as C_PI, C_TRUE, etc.
Avoid using reserved words or keywords as names, such as IF, CASE, DATA, etc.
Avoid using abbreviations or acronyms that are not widely known or understood, such as prc, fct, etc.
Avoid using names that are too long or too short, such as myVeryLongAndComplicatedVariableNameThatNobodyCanRemember, x, etc.
Comments are the text that is not executed by the compiler or interpreter, but is used to explain or document the code. Comments help to make the code more understandable, to provide additional information or context, and to facilitate debugging and maintenance.
Some of the guidelines for using comments in ABAP code are:
Use comments to describe the purpose and functionality of the code blocks, such as classes, methods, statements, etc.
Use comments to explain the logic and reasoning behind the code decisions, such as why a certain algorithm or data structure was chosen, what are the assumptions or limitations of the code, etc.
Use comments to highlight important or critical parts of the code, such as potential errors or bugs, special cases or exceptions, etc.
Use comments to mark unfinished or temporary parts of the code, such as TODOs, FIXMEs, etc.
Use inline comments to comment on single lines or expressions, such as "This is an inline comment".
Use block comments to comment on multiple lines or sections, such as "This is a block comment".
Use documentation comments to generate documentation for the code, such as "This is a documentation comment".
Use consistent and clear language and style for writing comments, such as using proper grammar, spelling, punctuation, etc.
Avoid using comments that are redundant, irrelevant, outdated, or misleading, such as repeating what the code already does, commenting on obvious or trivial things, leaving comments that do not match the current state of the code, or providing wrong or inaccurate information.
Indentation and Formatting
Indentation and formatting are the rules for arranging and presenting the code in a structured and organized way. Indentation and formatting help to make the code more readable, to show the hierarchy and flow of the code, and to improve consistency and aesthetics.
Some of the guidelines for indenting and formatting ABAP code are:
and use a consistent number of spaces for each indentation level, such as 2 or 4 spaces.
Use a new line for each statement or expression, and align them with the same indentation level.
Use a blank line to separate logical blocks of code, such as methods, loops, conditions, etc.
Use parentheses to enclose expressions that span multiple lines, and align them with the first character of the expression.
Use spaces around operators and keywords, such as a + b, IF x = y, etc.
Use spaces after commas and semicolons in lists and parameters, such as (a, b, c), DATA: x TYPE i; y TYPE c, etc.
Avoid using spaces before or after parentheses or brackets, such as (a + b), x, etc.
Avoid using spaces at the end or beginning of a line.
Avoid using multiple blank lines in a row.
Avoid using long lines that exceed a certain limit, such as 80 or 120 characters. Use line breaks and indentation to split long lines into shorter ones.
The ABAP-specific rules for programming are the principles that apply to the features and characteristics of the ABAP language. They include data types and declarations, operators and expressions, statements and control structures. These rules help to make the code more efficient, robust, and secure.
Data Types and Declarations
Data types and declarations are the rules for defining and using data objects in ABAP code. Data objects are the containers that store values of different types, such as numbers, strings, dates, etc. Data types and declarations help to ensure the validity, consistency, and compatibility of the data objects.
Some of the guidelines for data types and declarations in ABAP code are:
Use appropriate data types for data objects according to their purpose and range of values, such as I for integers, F for floating-point numbers, C for characters, D for dates, etc.
Use complex data types for data objects that consist of multiple components or attributes, such as structures, tables, references, etc.
Use data elements or domains to define reusable data types with semantic information and technical attributes, such as length, decimals, description, validation rules, etc.
Use constants or literals to define fixed values that do not change during the execution of the program, such as C_PI = '3.14159', C_TRUE = 'X', etc.
Use explicit declarations to define data objects before using them in the code, such as DATA: x TYPE i, DATA: y TYPE c LENGTH 10, etc.
Avoid using implicit declarations or conversions that rely on default data types or assignments, such as x = 1, y = 'Hello', etc.
Avoid using obsolete or deprecated data types or declarations that are no longer recommended or supported, such as P, N, BEGIN OF COMMON PART, etc.
Operators and Expressions
Operators and expressions are the rules for manipulating and evaluating data objects in ABAP code. Operators are the symbols that perform specific operations on one or more operands, such as arithmetic operations, logical operations, comparison operations, etc. Expressions are the combinations of operators and operands that produce a result, such as a + b, x > y, s && t, etc. Operators and expressions help to implement the logic and functionality of the code.
Some of the guidelines for operators and expressions in ABAP code are:
Use appropriate operators for different data types and operations, such as + - * / MOD DIV
for arithmetic operations, = > >=
for comparison operations, AND OR NOT XOR EQ NE GT GE LT LE
for logical operations, &
for string concatenation, ?
for conditional expression, etc.
Use parentheses to group expressions and to clarify the order of evaluation, such as (a + b) * c, x = (y > z) ? y : z, etc.
Avoid using ambiguous or confusing operators or expressions that may lead to unexpected results or errors, such as +
for string concatenation, =
for assignment, NOT x = y, etc.
Avoid using redundant or unnecessary operators or expressions that do not add any value or meaning to the code, such as x + 0, y * 1, IF x = TRUE, etc.
Statements and Control Structures
Statements and control structures are the rules for executing and controlling the flow of the code in ABAP. Statements are the instructions that perform specific actions or tasks, such as assignments, calculations, conditions, loops, branches, etc. Control structures are the constructs that determine the sequence and condition of the execution of the statements, such as IF-ELSE, CASE, WHILE, DO, etc. Statements and control structures help to implement the logic and functionality of the code.
Some of the guidelines for statements and control structures in ABAP code are:
Use appropriate statements for different actions or tasks, such as DATA for declarations, MOVE for assignments, COMPUTE for calculations, WRITE for output, CALL for method invocation, etc.
Use appropriate control structures for different scenarios or situations, such as IF-ELSEIF-ELSE-ENDIF for simple conditions, CASE-WHEN-OTHERS-ENDCASE for multiple choices, WHILE-ENDWHILE for indefinite loops, DO-ENDDO for definite loops, etc.
Use consistent and clear syntax and style for writing statements and control structures, such as using keywords in uppercase letters, using colons to separate statements on the same line, using periods to end statements on different lines, etc.
Avoid using obsolete or deprecated statements or control structures that are no longer recommended or supported, such as OCCURS, CHECK, EXIT, GOTO, etc.
Avoid using nested or complex statements or control structures that make the code difficult to read or understand, such as nested IFs, nested loops, nested CASEs, etc.
Avoid using redundant or unnecessary statements or control structures that do not add any value or meaning to the code, such as MULTIPLY x BY 1, CASE x WHEN 1 WHEN 2 WHEN 3 END CASE, etc.
Structure and Style
The structure and style guidelines for ABAP programming are the principles that apply to the organization and presentation of the code. They include modularity, readability, maintainability. These guidelines help to make the code more coherent, elegant, and professional.
Modularity and Reusability
Modularity and reusability are the rules for dividing and combining the code into smaller and independent units that can be reused and maintained easily. Modularity and reusability help to reduce code duplication, to improve code quality, and to facilitate collaboration and communication among developers.
Some of the guidelines for modularity and reusability in ABAP code are:
Use classes and methods to encapsulate data and behavior into objects that can be instantiated and manipulated by other objects.
Use interfaces to define contracts or specifications that classes can implement or inherit from.
Use function modules to define reusable functions that can be called by other programs or modules.
Avoid using global data or variables that can be accessed or modified by any part of the program. Use local data or variables that are only visible within a specific scope.
Avoid using hard-coded values or parameters that can limit the flexibility and adaptability of the code. Use dynamic values or parameters that can be changed or customized according to different situations.
Readability and Clarity
Readability and clarity are the rules for making the code easy to read and understand by humans. Readability and clarity help to improve code comprehension, to reduce code ambiguity, and to enhance code aesthetics.
Some of the guidelines for readability and clarity in ABAP code are:
Use meaningful and descriptive names for data objects, classes, methods, parameters, etc. that reflect their purpose and role.
Avoid using magic numbers or strings that have no obvious meaning or significance. Use constants or literals that have descriptive names and values.
Use comments to explain or document the code, especially for complex or critical parts.
Use indentation and formatting to structure and organize the code in a consistent and clear way.
Avoid using obscure or confusing syntax or style that can make the code hard to read or understand. Use simple and straightforward syntax or style that can convey the code intention clearly.
Avoid using excessive or unnecessary code that can make the code cluttered or verbose. Use concise and elegant code that can express the code functionality effectively.
Maintainability and Testability
Maintainability and testability are the rules for ensuring that the code can be modified and verified easily. Maintainability and testability help to improve code quality, to prevent or detect errors or bugs, and to facilitate debugging and maintenance.
Some of the guidelines for maintainability and testability in ABAP code are:
Use documentation comments to generate documentation for the code that describes the purpose, functionality, parameters, return values, exceptions, etc. of the classes, methods, function modules, etc.
Use unit tests to verify the correctness and functionality of the code by writing test cases that check the expected outputs or behaviors of the classes, methods, function modules, etc.
Use error handling to handle unexpected or exceptional situations that may occur during the execution of the code by using statements such as TRY-CATCH, RAISE, ASSERT, etc.
Avoid using hard-coded dependencies or assumptions that can make the code brittle or inflexible. Use dependency injection or configuration files to inject or specify the dependencies or assumptions dynamically.
Avoid using side effects or global states that can make the code unpredictable or inconsistent. Use pure functions or methods that only depend on their inputs and outputs.
Avoid using complex or monolithic code that can make the code difficult to modify or verify. Use modular or decoupled code that can be changed or tested independently.
The architecture guidelines for ABAP programming are the principles that apply to the design and structure of the code. They include layering, separation of concerns, design patterns. These guidelines help to improve code cohesion, coupling, and scalability.
Layering and Separation of Concerns
Layering and separation of concerns are the rules for dividing and organizing the code into different layers or components that have different responsibilities or concerns. Layering and separation of concerns help to reduce complexity, to increase reusability, and to enhance modifiability.
Some of the guidelines for layering and separation of concerns in ABAP code are:
Use model-view-controller (MVC) pattern to separate the data (model), presentation (view), and logic (controller) layers of an application.
Use business logic layer (BLL) to encapsulate the business rules and processes of an application.
Use data access layer (DAL) to abstract the access and manipulation of data sources such as databases, files, web services, etc.
Avoid mixing different layers or components in the same class, method, function module, etc. Use interfaces or dependency injection to communicate between different layers or components.
Avoid violating the layer hierarchy by calling a higher layer from a lower layer. Use events or callbacks to notify a higher layer from a lower layer.
Avoid creating circular dependencies between different layers or components. Use interfaces or abstraction classes to break circular dependencies.
Design Patterns and Best Practices
Design patterns and best practices are the rules for applying proven solutions or techniques to common problems or scenarios in ABAP programming. Design patterns and best practices help to improve code quality, to avoid reinventing the wheel, and to follow industry standards.
Some of the guidelines for design patterns and best practices in ABAP code are:
Use singleton pattern to ensure that only one instance of a class exists in the program.
Use factory pattern to create objects without exposing the creation logic or the concrete classes.
Use dependency injection to provide the dependencies of a class or a method without creating them inside the class or the method.
Use SOLID principles to design classes and methods that are single-responsibility, open-closed, Liskov substitution, interface segregation, and dependency inversion.
Use DRY principle to avoid repeating yourself in the code by extracting common functionality into reusable units.
Use KISS principle to keep it simple and stupid in the code by avoiding unnecessary complexity or sophistication.
The robustness guidelines for ABAP programming are the principles that apply to the reliability and security of the code. They include performance, security, quality. These guidelines help to improve code efficiency, to prevent or mitigate threats or attacks, and to adhere to standards or regulations.
Performance and Efficiency
Performance and efficiency are the rules for optimizing the speed and resource consumption of the code. Performance and efficiency help to improve user experience, to reduce costs, and to increase scalability.
Some of the guidelines for performance and efficiency in ABAP code are:
Use internal tables to store and process large amounts of data in memory.
Avoid using nested loops that can cause exponential growth in execution time. Use hash tables or binary search to improve lookup efficiency.
Use parallel processing to execute multiple tasks simultaneously or asynchronously.
Avoid using unnecessary or redundant calculations or operations that can waste CPU time or memory. Use caching or memoization to store interm