1. Fine-grained processing
of CVS archives with APFEL
Tom Zimmermann
Saarland University, Saarbrücken, Germany

2. Guiding developers
Zimmermann, Weissgerber, Diehl, Zeller (TSE 2005)

5. eROSE suggests further locations.

7. eROSE prevents incomplete changes.

8. eROSE is customizable.

9. APFEL collects CVS data
APFEL

10. APFEL collects CVS data
APFEL

11. APFEL collects CVS data
APFEL

12. Fine-grained changes
initDefaults(IPreferenceStore store)
public static void initDefaults(IPreferenceStore store) {
store.setDefault(OPEN_STRUCTURE_COMPARE, true);
store.setDefault(SYNCHRONIZE_SCROLLING, true);
store.setDefault(SHOW_PSEUDO_CONFLICTS, false);
store.setDefault(INITIALLY_SHOW_ANCESTOR_PANE, false);
store.setDefault(SHOW_MORE_INFO, false);
store.setDefault(IGNORE_WHITESPACE, false);
store.setDefault(PREF_SAVE_ALL_EDITORS, false);
//store.setDefault(USE_SPLINES, false);
store.setDefault(USE_SINGLE_LINE, true);
//store.setDefault(USE_RESOLVE_UI, false);
store.setDefault(PATH_FILTER, quot;quot;); //$NON-NLS-1$
}

13. Fine-grained changes
initDefaults(IPreferenceStore store)
public static void initDefaults(IPreferenceStore store) {
store.setDefault(OPEN_STRUCTURE_COMPARE, true);
D
store.setDefault(SYNCHRONIZE_SCROLLING, true);
E
store.setDefault(SHOW_PSEUDO_CONFLICTS, false);
G
store.setDefault(INITIALLY_SHOW_ANCESTOR_PANE, false);
N
A
store.setDefault(SHOW_MORE_INFO, false);
H
store.setDefault(IGNORE_WHITESPACE, false);
C
store.setDefault(PREF_SAVE_ALL_EDITORS, false);
//store.setDefault(USE_SPLINES, false);
store.setDefault(USE_SINGLE_LINE, true);
//store.setDefault(USE_RESOLVE_UI, false);
store.setDefault(PATH_FILTER, quot;quot;); //$NON-NLS-1$
}

14. Fine-grained changes
initDefaults(IPreferenceStore store)
public static void initDefaults(IPreferenceStore store) {
store.setDefault(OPEN_STRUCTURE_COMPARE, true);
Removed call to setDefault (2x):
store.setDefault(SYNCHRONIZE_SCROLLING, true);
store.setDefault(USE_SPLINES, false);
store.setDefault(SHOW_PSEUDO_CONFLICTS, false);
store.setDefault(INITIALLY_SHOW_ANCESTOR_PANE, false);
store.setDefault(USE_RESOLVE_UI, false);
store.setDefault(SHOW_MORE_INFO, false);
store.setDefault(IGNORE_WHITESPACE, false);
Inserted comments (2x):
store.setDefault(PREF_SAVE_ALL_EDITORS, false);
//store.setDefault(USE_SPLINES, false);
//store.setDefault(USE_SPLINES, false);
store.setDefault(USE_SINGLE_LINE, true);
//store.setDefault(USE_RESOLVE_UI, false);
//store.setDefault(USE_RESOLVE_UI, false);
store.setDefault(PATH_FILTER, quot;quot;); //$NON-NLS-1$
}

15. Collecting tokens
public static void main(String[] args) {
System.out.println(quot;Hello Portland.quot;);
System.out.println(“Hello eTX.”);
}

16. Collecting tokens
public static void main(String[] args) {
System.out.println(quot;Hello Portland.quot;);
System.out.println(“Hello eTX.”);
}
P-public T-String[]
P-static V-args
T-System T-System
V-out V-out
M-println M-println
Y-”Hello eTX.” Y-”Hello eTX.”

17. Collecting tokens
Modularization packages, imports
Inheritance extends, implements
Method calls inner vs final call
Variable usage identifiers, types
Exceptions throws, throw, catch
Comments Javadoc, blocks, lines
modifiers, literals,
Various operator, keywords

18. Comparing token sets

19. Comparing token sets
A()
B()
C()
D()
E()

20. Comparing token sets
A() A()
B() F()
C() B()
D() D()
E() E()

21. Comparing token sets
A() A()
B() F()
C() B()
D() D()
E() E()

22. Cross-cutting changes

23. Cross-cutting changes
SELECT token_name, COUNT(DISTINCT element_id)
FROM cvs_tokens_method NATURAL JOIN cvs_revisions
WHERE token_type='M' AND change_type='CHG'
GROUP BY transaction_id, token_name
ORDER BY COUNT(DISTINCT element_id) DESC;

24. Cross-cutting changes
SELECT token_name, COUNT(DISTINCT element_id)
FROM cvs_tokens_method NATURAL JOIN cvs_revisions
WHERE token_type='M' AND change_type='CHG'
GROUP BY transaction_id, token_name
ORDER BY COUNT(DISTINCT element_id) DESC;
token_name count
getString 1462
lock 1284
unlock 1284
error 996
isValidWidget 988

25. Cross-cutting changes
SELECT token_name, COUNT(DISTINCT element_id)
FROM cvs_tokens_method NATURAL JOIN cvs_revisions
WHERE token_type='M' AND change_type='CHG'
GROUP BY transaction_id, token_name
ORDER BY COUNT(DISTINCT element_id) DESC;
token_name count
getString 1462
ASPECTS?
lock 1284
unlock 1284
error 996
isValidWidget 988

26. Cross-cutting changes
SELECT token_name, COUNT(DISTINCT element_id)
FROM cvs_tokens_method NATURAL JOIN cvs_revisions
WHERE token_type='M' AND change_type='CHG'
GROUP BY transaction_id, token_name
ORDER BY COUNT(DISTINCT element_id) DESC;
token_name count
getString 1462
SOON!
lock 1284
unlock 1284 HAM: Cross-Cutting
error 996 Concerns in Eclipse
isValidWidget 988

27. One line fixes
301 Expression
150 Method call
120 Literal (boundaries, constants)
73 Keyword (true/false confusion)
60 Operator
39 Identifier
39 Comment (!!)

28. One line fixes
301 Expression
150 Method call
120 Literal (boundaries, constants)
73 Keyword (true/false confusion)
60 Operator
39 Identifier
39 Comment (!!)

29. One line fixes
301 Expression
150 Method call
120 Literal (boundaries, constants)
Bug report: 119638 - Typo in ToolItem.getControl
73 Keyword (true/false confusion)
252c252
* the item when the items is a codeSEPARATOR/code.
--- 60 Operator
* the item when the item is a codeSEPARATOR/code
39 Identifier
39 Comment (!!)

30. Future work
• Capture the context of a change, e.g.,
within an if/while/switch expression.
• Integrate with dynamic analysis, i.e.,
signature in addition to handles.
• Package and ship APFEL.

31. Conclusion
• APFEL collects CVS and change data.
• APFEL supports software evolution research,
in particular early testing of hypotheses.
• http://www.st.cs.uni-sb.de/softevo/

32. Conclusion
• APFEL collects CVS and change data.
• APFEL supports software evolution research,
in particular early testing of hypotheses.
• http://www.st.cs.uni-sb.de/softevo/
MSR Challenge 2007