Abstraction

  • Post category:Principles
  • Reading time:2 mins read

The abstraction principle in software systems allows us to create more generically usable software components.

Abstraction removes details from the problem space and thus makes it easier to think about problems and solutions. This principle lets us focus on problems by reducing complexity.

Abstraction makes software components more reusable: code for specific problems is abstracted to code that applies to a broader class of problems.

The process of abstraction, or generalization, removes specific attributes or functions and replaces these with general counterparts. The abstract components can be made specific through parameters or inheritance.

Abstraction is also a modeling technique that allows logical grouping of software structures so they can be better designed, realized, and maintained. Through this grouping, a complex software solution is methodically chopped up into smaller pieces that can be handled better in all phases of a software system lifecycle.

Examples of abstraction in software systems:

The OSI networking model abstracts communication protocols in functional layers.

Messaging middleware solutions abstract the connectivity logic from the application.

Picasso’s bull

Exchange an MVS dataset with Windows

  • Post category:Utilities
  • Reading time:2 mins read

I have discussed in another article how you can convert data from one codepage to another.

Also I have described a method to copy unix files to MVS datasets.

This article summarizes a method to copy an MVS dataset to Windows, while keeping records and converting from ebcdic to the utf8 codepage.

This job copies the MVS dataset to a UNIX files, indicating to keep record indicators with the Windows CR character (UNIX uses the CRLF typically as record / line separators). The dataset below ‘YOUR.TEST.PS’ should be a PS – physical sequential – dataset or a PDS(E) member.

//STEP1    EXEC PGM=BPXBATCH                                         
//STDOUT   DD SYSOUT=*                                               
//STDERR   DD SYSOUT=*                                                
//STDIN    DD DUMMY    
//* Values in STDENV below are kept but have no meaning for this function                                              
//STDENV   DD *                                                      
JAVA_HOME=/usr/lpp/java/J8.0_64                                      
PATH=/usr/lpp/mqm/web/bin:/bin:/usr/sbin                      
LIBPATH=/usr/lpp/mqm/java/lib                                 
//STDPARM  DD   *                                                    
SH cp -v -F cr "//'YOUR.TEST.PS'" /your/unixdir/tst.txt

You can now convert the EBCDIC data to UTF-8 as follows:

iconv -f 37 -t 1208 /your/unixdir/tst.txt  > /your/unixdir/utf8-tst.txt

Now you can transfer the file to Windows. Transfer the file in binary mode, otherwise another unwanted code page conversion will happen.