Naming Conventions in ABAP Objects 
Global classes and
interfaces that you create in the Class Builder are stored in the class
library and administered by the R/3 Repository: they therefore have the same
namespace as all other Repository objects (database tables, structures, data
elements, and so on).
It is therefore necessary to have naming conventions for object types and
their components and to use them uniformly within program development.
The following
naming convention has been conceived for use within the SAP namespace:
If you do not observe the naming conventions for object types (classes and
interfaces), conflicts will occur when the system creates persistent classes,
since it will be unable to generate the necessary co-classes.
Namespace for Components
A single namespace within a class is shared by:
§ All components of the class itself (attributes, methods, events, constructors, interfaces, internal data types in the class, and aliases)
§ All public and protected components of the superclasses of the class.
Method implementation has a local namespace. The names of the local variables can obscure those of class components.
Naming Convention
The naming convention has been kept as general as possible to avoid adversely influencing the naming of objects.
General Remarks
When you choose names for development objects, you should:
· Use English names
§ Use glossary terms when possible
For example, CL_COMPANY_CODE instead of BUKRS
§ In compound names, use the underscore character (_) as a separator. Since names are not case-sensitive, this is the only character that you can use to separate names.
Example: CL_COMPANY_CODE, CL_GENERAL_LEDGER_ACCOUNT
§ Names should describe the action, not the implementation of the action.
Example: PRINT_RECTANGLE, not RECTANGLE_TO_SPOOL
Conventions for Object Types
Class and interface names in the class library belong to the same namespace as data elements, tables, structures, and types. They are maintained centrally in table TADIR.
Class in the class library |
CL_<class name> The class name should be made up of singular nouns. CL_COMPANY_CODE, CL_GENERAL_LEDGER_ACCOUNT |
Interfaces in the class library |
IF_<interface name> The same naming convention applies to interfaces as to classes. IF_STATUS_MANAGEMANT, IF_CHECKER |
Local classes in programs |
LCL_<class name> The class name should be made up of singular nouns. LCL_TREE_MANAGEMENT |
Local interfaces in programs |
LIF_<interface name> The sane naming convention applies to interfaces as to classes. LIF_PRINTER |
Recommended naming conventions are not compulsory. However, if you use prefixes for these class and interface names, you should use those listed above.
Conventions for Components
Method name |
<method name> Method names should begin with a verb: GET_STATUS, CREATE_ORDER, DETERMINE_PRICE |
Events |
<event name> Event names should have the form BUTTON_PUSHED, COMPANY_CODE_CHANGED, BUSINESS_PARTNER_PRINTED |
Local type definitions within a class |
TY_<type name> TY_INTERNAL_TYPE, TY_TREE_LIST |
Data definitions (variables) |
<variable name> When you name variables within a class (CLASS-DATA or DATA), avoid using verbs at the beginning of the name (to avoid conflicts with method names). LINE_COUNT, MARK_PRINTED, MARK_CHANGED, STATUS |
Data definitions (constants) |
CO_<constant name> CO_MAX_LINE, CO_DEFAULT_STATUS, CO_DEFAULT_WIDTH, CO_MAX_ROWS |
Recommended naming conventions are not compulsory. However, if you use prefixes for these class and interface names, you should use those listed above..
Concrete Method Descriptions
Attribute access |
SET_<attribute name>, GET_<attribute name> Methods that access attributes of any kind should be prefaced with GET_ or SET_. GET_STATUS, SET_USE_COUNT |
Event handler methods |
ON_<event name> Methods that handle events should begin with ON, followed by the name of the event that they handle. ON_BUTTON_PUSHED, ON_BUSINESS_PARTNER_PRINTED |
Methods that perform type conversions |
AS_<new type> AS_STRING, AS_ISOCODE |
Methods that return a Boolean value These methods may not return any exceptions. Recommendation: Use SPACE and 'X' to represent false and true respectively. |
IS_<adjective> IS_OPEN, IS_EMPTY, IS_ACTIVE |
Check methods |
CHECK_<objective> CHECK_AUTHORIZATION, CHECK_PROCESS_DATE |
Local Conventions Within Methods
For parameters
The parameters are regarded from the point of view of the method that implements them:
IMPORTING parameters |
IM_<parameter name> |
EXPORTING parameters |
EX_<parameter name> |
CHANGING parameters |
CH_<parameter name> |
RESULT |
RE_<result> |
Using prefixes is NOT compulsory. However, if you do use them, use those listed above.
For exceptions
The following table contains a series of possible exception names, that can also be used generically (for example, NOT_FOUND could also be used as DATE_NOT_FOUND)
EXCEPTION |
Meaning |
ACTION_NOT_SUPPORTED |
The requested action or function code is not supported. |
CANCELLED |
If a method uses a dialog to find out what has to be dome (for example, a list of choices), and the user chooses "Cancel", you can set this exception. |
EXISTING |
A new object that you want to create already exists in the database. |
FAILED |
The method could not be executed because of the current environment. This exception is intended for cases where the method cannot be executed because of variable system circumstances. |
..._FAILED |
Part of the method could not be completed because of the current environment. (OPEN_FAILED, CLOSE_FAILED, SELECTION_FAILED, AUTHORIZATION_FAILED) |
FOREIGN_LOCK |
Data is locked by another user. |
INCONSISTENT |
Object data in the database is inconsistent. |
..._INCONSISTENT |
The component data for … of an object in the database is inconsistent. |
INVALID |
The object data entered is incorrect (for example, company code does not exist). Compare NOT_QUALIFIED. |
..._INVALID |
The component data entered for an object is incorrect. Compare NOT_QUALIFIED. |
INTERNAL_ERROR |
Last resort. Only use this exception if you cannot be more precise about the nature of the error. |
NOT_AUTHORIZED |
The user does not have the required authorization. |
NOT_CUSTOMIZED |
The object requested is not correctly customized. |
..._NOT_CUSTOMIZED |
The component … of the requested object is not correctly customized. |
NOT_FOUND |
Unable to find the requested object. |
..._NOT_FOUND |
Unable to find component … of the requested object. |
NOT_QUALIFIED |
The combination of input parameters is insufficient to run the method. Compare INVALID. |
..._NOT_QUALIFIED |
One parameter of the method is not qualified. |
NUMBER_ERROR |
Error assigning a number. |
SYSTEM_ERROR |
This exception is set if the system returns an unexpected error message. |