One of the flavors of ABAP classes (Global Classes) we have already discussed in the last article. Another flavor of ABAP class are Local Classes. The only difference between a local class & global class is visibility & accessibility. A local class can be accessed within that program only in which it is being defined & implemented, whereas a global class can be accessed in any other program.
NOTE: In some of the previous articles, where different types of classes have been described, there the sample programs were the examples of local class only.
A class which is defined and implemented in a program is known as Local Class. Local classes in SAP ABAP can be created through Transaction code SE-38(tool to create a report).
Let’s take an example of this class ‘ZCL_MARA’. This class is having one method ‘GET_MATERIAL_TYPE’ to get the material type of a given material.
NOTE: ‘MARA’ is a table in SAP ABAP for general material data. So, in this sample program, material (iv_matnr – importing parameter of a method) is given by the user, and this method will fetch the material type ( like finished, semi-finished, raw, etc. )
TYPES: BEGIN OF ty_mara, “USER-DEFINED TYPES
Matnr TYPE mara-matnr,
Mtart TYPE mara-mtart,
END OF ty_mara.
CLASS zcl_mara DEFINITION.
IMPORTING iv_matnr TYPE mara-matnr
EXPORTING ls_mara type ty_mara.
ENDCLASS. “CLASS DEFINITION
CLASS zcl_mara IMPLEMENTATION.
SELECT SINGLE matnr, mtart FROM mara INTO ls_mara
WHERE matnr = iv_matnr
ENDCLASS. “CLASS IMPLEMENTATION
- To restrict the usage of any functionality, we can use it in a local class of any program.
- A Local class is very useful while creating an ABAP Unit Test Class, as a local test class has been generated within a global class.
- These classes are useful for the enhancements of class methods.