Development language of the SAP system-ABAP Introduction

This is an article I contributed to my internal magazine to introduce sap development technology to colleagues who do not know about sap development. This article is intended to help you who want to learn sap development technologies.

The full name of ABAP is advanced business application programming-advanced business application programming language. The underlying source code of mysap ECC 6.0 is all written using ABAP. Therefore, the ABAP language must be used for secondary development of the system, including function development, report development, and excuse development.

First, let me introduce the features of the apab development platform.

In a sense, ABAP is not only a development language, but also a development tool, it is more like a complete Client/Server Development Environment Based on SAP myerp software suite. In comparison, Microsoft's visiual studio is a development environment, and VB, VC ++, and so on are development tools.

Let's take a look at the three-tier architecture of the SAP development environment.

Presentation (presentation layer) is a user-oriented program interface consisting of many screens. The application layer processes user logic and connects to the database layer to obtain data. Generally, development is performed at the application level. You can modify or add the corresponding business logic based on your needs. When some business requirements cannot be implemented through the system's default input interface, you can also add a specific user interface at the presentation layer.

ABAP is highly efficient in report development thanks to its close integration with sap. For database access, ABAP can use native SQL or open SQL. When native SQL is used, the development environment will directly send SQL statements to the underlying database for faster execution speed, it is difficult to track errors. Open SQL is an SQL language integrated into the ABAP development environment. It can be written together with the ABAP code and used in combination. The ABAP dictionary maps transparent tables to the underlying database tables. When we use open SQL in ABAP, it is irrelevant to the specific database type. Open SQL reads transparent tables to operate database tables.

The following describes the language features of ABAP from the programming language itself.

ABAP is an interpreted language. It is similar to VB in that it can track the execution process of a program and assign values to variables during the tracking process. This is helpful for tracking program bugs. Of course, due to the defects of interpreted language, the execution speed of ABAP is slower than that of compiled language. In the first few versions of ABAP, it does not support object-oriented technology. All programs written are process-oriented. With the development of technology, ABAP has added support for object-oriented technology in the new version.

Now Java is a common development language and is familiar to everyone. Let's take a look at the similarities and differences between ABAP and Java in terms of syntax and supported features.

1. ABAP is similar to Java and supports the definition of classes:

Java: Class myclass {

Public myclass (string ID ){

}

}

ABAP: Class myclass definition.

Public section.

Constructor importing ID type string.

Endclass.

2. There are some differences between the two in the way variables are defined.

Java: Private int mynum

ABAP: private section.

Data mynum type I.

3. ABAP can also throw an exception.

Java: Public void getmynum (INT mynum, myclass example)

Throws myclassexception.

ABAP: public section.

Methods:

Getmynum importing

Mynum

Example Type ref to myclass

Raising cx_myclass

From the above points, we can see that apart from syntax formats, ABAP and Java have great similarities in the support of object-oriented technology.

Of course, there are still many differences between the two. The biggest difference is that ABAP is integrated on the SAP system, and the bottom layer is the sap ABAP virtual machine, the program used to develop the C/S architecture. Java is a common development language that can be used to develop various platforms in various fields. The underlying layer is JVM. Generally, it is developed based on B/S architecture.