Creating Attributes 

You must already have created the internal data types in the class to which you want to refer when you create the attributes. See also : Creating Internal Types in Classes.

1. Select the class or interface and change to the Class Editor.
2. Choose Attributes.
3. To create an attribute, make the following entries:
   
   - Attribute
   Define a unique name with which the attribute is identified. Remember to observe the naming conventions in ABAP Objects.
   
   - Type
   You can specify an attribute as a constant, an instance attribute, or a static attribute (that is shared by all instances of the class).
   
   - Visibility
   Define the visibility of attributes for the user of the class. Public assigns the attribute to the public area of the class and the attribute can be called by every user of the class. Remember that public attributes form part of the external point of contact to the class, and as such stand in the way of full encapsulation.
   Attributes that are protected are visible and can be used by the class itself and any of its subclasses.
   Attributes that are private are only visible in and available to the class itself. Private attributes therefore are not visible in the subclasses.
   
   - Modeled only
   If you have selected this option, the system does not enter the interface in the class pool. You cannot access the components at runtime.
   
   - Typing method
   ABAP keyword for defining the type reference. You can choose one of the following: Type, Like or Type Ref To (for class references).
   
   - Reference type
   You can use any elementary ABAP type (including generic types) or object type (classes and interfaces).
   
   - Read-Only
   This option restricts the changeability of attributes as well as visibility. Users cannot change the attribute if a flag is set.
   
   - Description
   Short description of the components.
   
   - Initial value
   You must enter an initial value for constants.