ABAP is a
proprietary programming language, the software company SAP, which was developed
for the programming of commercial applications in the SAP environment and is
similar in its basic structure of the COBOL programming language.
Originally, the
acronym for "General report preparation processor", since this
language only customer-specific evaluations were programmed, but no database
changes could be made. During further development of the language the acronym
now stands for "Advanced Business Application Programming." The
language set is not defined and fixed in the past has repeatedly extended, for
example, the object-oriented language commands in ABAP Objects.
Since 1990, all
based on SAP-R/3-Module ABAP, which was taken over from the previous SAP R / 2.
Since the introduction of SAP NetWeaver, SAP ABAP offers a workflow and
programming environment for Java, and accordingly an ABAP-based and Java-based
application server (see SAP NetWeaver Application Server).
Properties
ABAP is a 4GL
language that is specifically designed for bulk data processing in commercial
applications, and offers the following advantages compared with elementary
languages in which those functions are located in libraries:
- Open SQL as the language integrated database access
- In the ABAP runtime environment integrated performance optimization of database access via the SAP buffering
- Internal tables for dynamic storage and processing of tabular data in the mass memory
- Integrated into the ABAP runtime environment concept of online transaction processing (OLTP), where many users simultaneously access to the central database
- Language in the integrated interface to other programming environments via Remote Function Call
- Language in the integrated interface to XML.
The integration
of such features in the language is essentially beneficial for static
verifiability and the execution speed of programs. In turn, it also contains
much more ABAP language elements than other languages.
ABAP supports on
subroutines and function modules based, procedural and release 6.10 one based
on classes and interfaces, object-oriented programming model. Both models are
interoperable.
Backward
Compatibility
SAP operates in
the development of ABAP, the principle of backward compatibility. If an ABAP
statement is replaced by a newer (eg performant) statement, it loses the old
statement is not valid or function. As the old instructions in addition to the
new instructions continue to exist, the result is a very extensive language
support. Ancient language elements should not be used anymore, but the use is
entirely possible. Only when using ABAP OO (ABAP objects), some old parts no
longer be used.
The advantage is
that the recent developments and customer adjustments remain functional and
their behavior does not change. Developments need not be revised. The
disadvantage is that developers often resort to more old components, although
newer and more effective (performant) language components are present. For
newcomers language, this means that both the old and the new parts components
have to be learned. In addition, this increases the complexity and scope of the
language.
Old and new
components can be combined, so in object code (program code) can also be used
procedural elements, so did the use of object-oriented elements in procedural
coding possible. The systematic combination of new and old parts, the power of
language can be increased.
ABAP Workbench
The ABAP
programming is supported by a development environment that is designed to
enable large projects with multiple (hundreds) developers. Here, at any time
must have a running system to be guaranteed. To the changed objects are
recorded in so-called transportation orders, which are exported to the file
system when released and can be imported into subsequent systems. This
mechanism allows the development of programs of their productive use in
isolation.
The development
environment for ABAP programming language is also developed in ABAP Workbench.
In the ABAP Workbench (access via the so-called Object Navigator, transaction
SE80), however, other objects such as BSP (Business Server Pages with HTML
content) are processed.
The special
feature is the so-called "forward navigation." Thus, a double click
on a table name directly to the definition of the database table in the ABAP
Dictionary, while double-clicking directly on a method name into this method.
The ABAP
Workbench is adjusted over time to meet the requirements of modern software
development. Since the previous release, for example, syntax highlighting is
supported.
ABAP Objects
ABAP Objects
refers to the object-oriented extensions to the programming language ABAP. It
implements all the elements of object-oriented programming (OOP) with the
exception of multiple inheritances and method overloading. Interfaces and
optional parameters are supported. With special RTTI classes also reflexive
programming is possible, even from the version 6.40 (limited) the dynamic
creation of new types.
ABAP Objects
from SAP Release 4.6 is available and since then continuously improved and
supplemented eg by Object Services. The object-oriented language elements are
essential for the development of advanced user interfaces with controls and for
the implementation of web applications and XML services in ABAP. Large parts of
the ABAP Workbench itself are implemented in object-oriented ABAP Objects.
ABAP Objects
restricts the language range of "classic" ABAP in some respects. For
example, an internal table with a header in the context of ABAP Objects is no
longer allowed.
Web Dynpro
As of SAP
NetWeaver 7.0 is available with WebDynpro for ABAP to develop the possibility
web applications in ABAP. Web Dynpro ABAP based on the Web Dynpro technology.
SAP originally wanted to make this technology available for the Java
programming language (from NetWeaver 6.40) are available. Based on customer
requests (missing java expertise in ABAP developers or missing SAP expertise in
Java developers) decided to integrate this technology into SAP ABAP.
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