ABAP - Time period intersection tool

[jrgkraus]

After several times I encounterd the need for calculating the intersection of two time periods, I finally decided to create a reusable tool.

The tool not only decides wether two periods intersect or not (see also https://blogs.sap.com/tag/timeslice/) but returns also the intersection period. You can use it only with clocktime, dates or both.

Here's the class coding:

class zcl_tool_time_slices definition

  public

  create public .



  public section.



    types:

      begin of ty_period,

        date_from type d,

        time_from type t,

        date_to   type d,

        time_to   type t,

      end of ty_period .



    class-methods intersect

      importing

        first_period      type ty_period

        second_period     type ty_period

      returning

        value(r_intersect) type ty_period.

  protected section.

  private section.

ENDCLASS.







CLASS ZCL_TOOL_TIME_SLICES IMPLEMENTATION.





* <SIGNATURE>---------------------------------------------------------------------------------------+

* | Static Public Method ZCL_TOOL_TIME_SLICES=>INTERSECT

* +-------------------------------------------------------------------------------------------------+

* | [--->] FIRST_PERIOD                   TYPE        TY_PERIOD

* | [--->] SECOND_PERIOD                  TYPE        TY_PERIOD

* | [<-()] R_INTERSECT                    TYPE        TY_PERIOD

* +--------------------------------------------------------------------------------------</SIGNATURE>

  method intersect.



    r_intersect = cond #(

      let

        " concatenate date and time for easier comparison

        first_from = first_period-date_from && first_period-time_from

        second_from = second_period-date_from && second_period-time_from

        first_to = first_period-date_to && first_period-time_to

        second_to = second_period-date_to && second_period-time_to in

      when

        " very slim decision wether an intersection exists or not

        first_from < second_to and

        second_from < first_to

      then value #(

        let

          from = cond #(

            when first_from > second_from then first_from else second_from )

          to = cond #(

            when first_to > second_to then second_to else first_to ) in

        date_from = from(8)

        time_from = from+8

        date_to = to(8)

        time_to = to+8 ) ).



  endmethod.

ENDCLASS.

You can play around with the class using this report

report zp_tmp_intersect.



parameters:

  p1_datef type d, p1_timef type t, p1_datet type d, p1_timet type t,

  p2_datef type d, p2_timef type t, p2_datet type d, p2_timet type t.



start-of-selection.

  cl_demo_output=>display( zcl_tool_time_slices=>intersect(

    first_period  = value #(

      date_from = p1_datef

      time_from = p1_timef

      date_to = p1_datet

      time_to = p1_timet )

    second_period  = value #(

      date_from = p2_datef

      time_from = p2_timef

      date_to = p2_datet

      time_to = p2_timet ) ) ).