ABAP Regular Expressions Usage

Requirement: 

Filter strings of pattern LNN_NNNN_NN_LL (L – Letter, N – Number) from a list Eg: Z00_0002_01_AA, Z01_0015_02_AA etc.

Solution:

Used SAP regular expressions (REGEX) concept to get this done in a program. It makes string, integer and special character comparisons much simpler.

'\<Z\d\d_\d\d\d\d_\d\d_\D\D\>' is the matching pattern in terms of regular expressions for a string like ‘Z00_0002_01_AA’.

DATA: c_pattern TYPE string VALUE '\<Z\d\d_\d\d\d\d_\d\d_\D\D\>'.

DATA:lv_match   TYPE abap_bool,
     lr_matcher TYPE REF TO cl_abap_matcher.

lr_matcher = cl_abap_matcher=>create( 

pattern     = c_pattern
      ignore_case = 'X'
      text        = ‘Z00_0002_01_AA’ ).

lv_match = lr_matcher->match( ).

If lv_match = ‘X’ then it is a match.

Special characters used	Meaning
\d	Placeholder for any single digit
\D	Placeholder for any character other than a digit
\<	Start of a word
\>	End of a word

There is a standard program available to check REGEX Functionality DEMO_REGEX_TOY. Below are few screens from the same.

Finding the pattern: