Runtime Class for Expressions

Use

If you want to realize an own expression type, you must also implement a runtime class in addition to the maintenance class and the associated subscreen.

We recommend that you implement your runtime class on the basis of basis class CL_EXPRESSION_BASE_BRF.

If you implement your runtime class on the basis of CL_EXPRESSION_BASE_BRF, you only have to redefine the following methods:

• INITIALIZE

• PROCESS_SPECIFIC

The other methods have already been implemented by the base class. This means that you do not have to redefine the method.

In the description of the methods INITIALIZE and PROCESS_SPECIFIC, class CL_EXPRESSION3_BRF (for the expression type Three Operand Arithmetic) serves as an example. This class is derived from basis class CL_EXPRESSION_BASE_BRF. You can use class CL_EXPRESSION3_BRF to calculate the logical link of up to three Boolean expressions.