This document discusses software language evolution and coupled heterogeneous evolution. It presents a generic architecture for specifying data model evolutions using a domain-specific transformation language. This includes basic transformations, a positioning language, and syntax for specifying model evolutions. The architecture generates interpreters for automatic migration between heterogeneous models. The work focuses on evolution across multiple domains and software languages.

1. Sander Vermolen
Eelco Visser
Software
Language
Evolution
This research was supported by NWO/JACQUARD project
638.001.610, MoDSE: Model­Driven Software Evolution.

3. Data
Models

6. User
name :: varchar
email :: tinytext
Page
title :: varchar
author  User
content :: text

7. User
name bob
email b.johnson@mail.com
Page
title "The first page"
content "Hello world"
author bob

8. Version history

9. User User
name :: varchar name :: varchar
email :: tinytext email :: tinytext
Page Page
title :: varchar title :: varchar
content :: text
author  User
Revision
page  Page
revisionText :: text
author  User

10. User User
name bob name bob
email b.johnson@... email b.johnson@...
Page 1 Page 1
title "The first page" title "The first page"
content "Hello world"
author bob
Revision 1
page {page 1}
revisionText "Hello world"
author bob

11. Coupled Data Evolution

12. ...
$dbh->bz_add_column('attachments', 'submitter_id', {TYPE => 'INT3', NOTNULL => 1}, 0);
$dbh->bz_rename_column('bugs_activity', 'when', 'bug_when');
_add_bug_vote_cache(); _update_product_name_definition(); _add_bug_keyword_cache();
$dbh->bz_add_column('profiles', 'disabledtext', {TYPE => 'MEDIUMTEXT', NOTNULL => 1}, '');
_populate_longdescs(); _update_bugs_activity_field_to_fieldid();
if (!$dbh->bz_column_info('bugs', 'lastdiffed')) {
$dbh->bz_add_column('bugs', 'lastdiffed', {TYPE =>'DATETIME'});
$dbh->do('UPDATE bugs SET lastdiffed = NOW()');
}
_add_unique_login_name_index_to_profiles();
$dbh->bz_add_column('profiles', 'mybugslink', {TYPE => 'BOOLEAN', NOTNULL => 1, DEFAULT => 'TRUE'});
_update_component_user_fields_to_ids();
$dbh->bz_add_column('bugs', 'everconfirmed', {TYPE => 'BOOLEAN', NOTNULL => 1}, 1);
$dbh->bz_add_column('products', 'maxvotesperbug',
{TYPE => 'INT2', NOTNULL => 1, DEFAULT => '10000'});
$dbh->bz_add_column('products', 'votestoconfirm', {TYPE => 'INT2', NOTNULL => 1}, 0);
_populate_milestones_table();
$dbh->bz_alter_column('bugs', 'target_milestone', {TYPE => 'varchar(20)', NOTNULL => 1, DEFAULT => "'---'"});
$dbh->bz_alter_column('milestones', 'value', {TYPE => 'varchar(20)', NOTNULL => 1});
_add_products_defaultmilestone();
if (!$dbh->bz_index_info('cc', 'cc_bug_id_idx') || !$dbh->bz_index_info('cc', 'cc_bug_id_idx')->{TYPE}) {
$dbh->bz_drop_index('cc', 'cc_bug_id_idx');
$dbh->bz_add_index('cc', 'cc_bug_id_idx', {TYPE => 'UNIQUE', FIELDS => [qw(bug_id who)]});
}
if (!$dbh->bz_index_info('keywords', 'keywords_bug_id_idx') || !$dbh->bz_index_info('keywords',
'keywords_bug_id_idx')->{TYPE}) {
$dbh->bz_drop_index('keywords', 'keywords_bug_id_idx');
$dbh->bz_add_index('keywords', 'keywords_bug_id_idx', {TYPE => 'UNIQUE', FIELDS => [qw(bug_id
keywordid)]});
}
...

13. Evolving
Data Models

15. 8 Basic Transformations
add or remove entity add or remove property
change name of entity change name of property
change type of set change type of property

16. add
Revision
page  Page
author  User
add
revisionText :: text

18. Revision
revisionText :: text
at Entity Revision / Property page
add revisionText :: text

19. Revision
revisionText :: text
at Entity Revision / Property page
add revisionText :: text
from page.content

20. at Entity Page
add Revision
;
at Entity Revision / Property page
add revisionText :: text
from page.content

21. Evolving
Data Models
8 Basic transformations
Syntax for the transformations
Positioning language
Specify data model evolutions

22. Data
Migration

24. Technical Domain
WebDSL
Stratego/XT
Java
Java Persistence API
Object Transformation Library

25. at Entity Page
remove author
transform (Page) to (Page) {
DropAttribute("author");
}

26. at Entity Revision / Property page
add revisionText :: text
from page.content
transform (Page) to (Revision) {
AddAttribute("revisionText",
getPage().getContent() )
}

27. But wait, there’s more!
More abstract transformations
Type conversions
Java type generation

28. Data
Migration

29. Heterogeneous
Coupled Evolution

32. Horizontal Generalization
Domain

34. Lists
More types
Abstract types

35. Vertical Generalization
Conformance level

36. Heterogeneous
Coupled Evolution
of
Software Languages
Evolving Software Language
Data Model
Software
Data

37. A Generic
Architecture

41. Domain Specific
Transformation Language
(DSTL)
Transformation Interpreter
Software Migration

42. SDF SDF
Stratego

43. Lists [...]
Entity* ­> DataM
"add" Entity ­> LocalTransformation
"remove" ­> LocalTransformation

44. Lexicals ''...''
Id "::" Type ­> Prop
"substitute" Id ­> LocalTransformation

45. Multiple productions ­>*
"int" ­> Type
"bool" ­> Type
Id ­> Type
"set of" Type ­> Type
"substitute" Type ­> LocalTransformation

46. Type checking .../...
"at" APath LocalTransformation ­> Transformation

47. Software Language
Evolution Heterogeneous coupled evolution
Generic architecture
DSTL generation
Evolution interpreter generation
Automatic migration
Application to data models

48. Software
Language
Evolution
This research was supported by NWO/JACQUARD project
638.001.610, MoDSE: Model­Driven Software Evolution.

50. Present & Future
Evolution detection
Validation
Usability
Abstractions

51. Related work
Focus on single domain
Meta modeling
[7, 23, 17, 10]
DSLs
[23]
Data base schemas
[15,4,2,8,1]