Quality Assessment of Embedded Language Modules: Targeting the spotlight on heterogeneous systems

Transcription

1 Quality Assessment of Embedded Language Modules: Targeting the spotlight on heterogeneous systems Martin van der Vlist Laboratory for Quality Software (LaQuSo)

2 Overview Introduction COBOL Approach Results Java Approach Results Conclusions Current work Future work PAGE 2

3 Introduction LaQuSo: code analysis is core activity Embedded language recurring issue Often SQL/Database intensive applications Metrics/dependencies for host and embedded language available No measurement for interaction Not much research information available PAGE 3

4 Research questions How can the combination of embedded language fragments and host language statements be analyzed? When analyzing embedded language fragments and host language statements, can relevant metrics be calculated and dependencies be analyzed? PAGE 4

5 Common approach Based on existing tools: SQuAVisiT 2 different host-languages: COBOL + PL/SQL Java + SQL Include case studies Legacy COBOL system 2 Java ERP systems Small Java program PAGE 5

6 COBOL: example IDENTIFICATION DIVISION. PROGRAM-ID. XAG1P626. * skipped all initializations etc MOVE HIA-DATUM-INGANG OF PAR TO HIA-DATUM-INGANG OF Q4 MOVE HIA-VOLGNUMMER OF PAR TO HIA-VOLGNUMMER OF Q4 PERFORM M ACCESS-BLOCK * a lot of methods in between M ACCESS-BLOCK SECTION. M ACCESS-BLOCK-PAR. EXEC SQL SELECT XAP626.HIA_HEFFINGSGRONDSLAG INTO :A4.HIA-HEFFINGSGRONDSLAG FROM XAP626 WHERE ( TO_CHAR(XAP626.HIA_DATUM_INGANG, 'YYYYMMDD') = :Q4.HIA-DATUM-INGANG AND XAP626.HIA_VOLGNUMMER = :Q4.HIA-VOLGNUMMER ) END-EXEC. M ACCESS-BLOCK-EX. EXIT. PAGE 6

7 COBOL:approach Parse COBOL program using generated parser = y = 42 * (x + 481) y * x PAGE 7

8 COBOL:approach Parse COBOL program using generated parser regarding SQL statements as 1 token IDENTIFICATION DIVISION. PROGRAM-ID. XAG1P626. M ACCESS-BLOCK-PAR * skipped all initializations etc MOVE HIA-DATUM-INGANG OF PAR TO HIA-DATUM-INGANG OF Q4 MOVE HIA-VOLGNUMMER OF PAR TO HIA-VOLGNUMMER OF Q4 PERFORM M ACCESS-BLOCK * a lot of methods in between M ACCESS-BLOCK SECTION. M ACCESS-BLOCK-PAR. EXEC SQL SELECT XAP626.HIA_HEFFINGSGRONDSLAG INTO :A4.HIA-HEFFINGSGRONDSLAG FROM XAP626 WHERE ( TO_CHAR(XAP626.HIA_DATUM_INGANG, 'YYYYMMDD') = :Q4.HIA-DATUM-INGANG AND XAP626.HIA_VOLGNUMMER = :Q4.HIA-VOLGNUMMER ) END-EXEC. M ACCESS-BLOCK-EX. EXIT. SQLStatement EXEC SQL END-EXEC SELECT XAP626.HIA_HEFFINGSGRONDSLAG XAP626.HIA_VOLGNUMMER = :Q4.HIA-VOLGNUMMER ) PAGE 8

9 COBOL: approach Parse COBOL program regarding SQL statements as 1 token After COBOL-analysis, parse SQL statements (using existing SQL parser) Analyze dependencies between modules and tables Compute metrics separately PAGE 9

10 COBOL: case study Large pension fund COBOL/PL-SQL system 2816 files, 1603 files with queries 1.62 Million lines of code PAGE 10

11 COBOL results: metrics Number of queries per module 7 modules: > modules: 1 One file contains all stored procedures Number of tables per module Max number of tables: modules > 1 (out of 1603) PAGE 11

12 COBOL results: metrics 106 NOT SUPPOSED TO READ THIS 33 PAGE 12

13 COBOL results: dependencies PAGE 13

14 COBOL results: dependencies PAGE 14

15 COBOL results: dependencies PAGE 15

16 COBOL results: dependencies PAGE 16

17 COBOL results: dependencies PAGE 17

18 Java: example //running example public int getcustomercredit(int id) throws SQLException { String sql = "SELECT cd.credit "; sql += "FROM CustomerDetails cd" + "WHERE cd.category = " + this.getcategory(); if (this.restrict) { sql += " AND cd.restriction = 1"; } sql += " AND cd.id =?"; PreparedStatement s = this.con.preparestatement(sql); s.setint(1, id); ResultSet rs = s.executequery(); rs.next(); return rs.getint( credit"); } PAGE 18

19 Java: the issue IDENTIFICATION DIVISION. PROGRAM-ID. XAG1P626. * skipped all initializations etc MOVE HIA-DATUM-INGANG OF PAR TO HIA-DATUM-INGANG OF Q4 MOVE HIA-VOLGNUMMER OF PAR TO HIA-VOLGNUMMER OF Q4 PERFORM M ACCESS-BLOCK * a lot of methods in between M ACCESS-BLOCK SECTION. M ACCESS-BLOCK-PAR. EXEC SQL SELECT XAP626.HIA_HEFFINGSGRONDSLAG INTO :A4.HIA-HEFFINGSGRONDSLAG FROM XAP626 WHERE ( TO_CHAR(XAP626.HIA_DATUM_INGANG, 'YYYYMMDD') = :Q4.HIA-DATUM-INGANG AND XAP626.HIA_VOLGNUMMER = :Q4.HIA-VOLGNUMMER ) END-EXEC. M ACCESS-BLOCK-EX. EXIT. SQL //running example public int getcustomercredit(int id) throws SQLException { String sql = "SELECT cd.credit "; sql += "FROM CustomerDetails cd" + "WHERE cd.category = " + this.getcategory(); if (this.restrict) { sql += " AND cd.restriction = 1"; } sql += " AND cd.id =?"; PreparedStatement s = this.con.preparestatement(sql); s.setint(1, id); ResultSet rs = s.executequery(); rs.next(); System.out.println( Query executed"); return rs.getint( credit"); } SQL parts Not SQL PAGE 19

20 Java: approach public int getcustomercredit(int id) throws SQLException { String sql = "SELECT cd.credit "; sql += "FROM CustomerDetails cd" + # of String Parts = 6 "WHERE cd.category = " + this.getcategory(); # Of Decisions =1 if (this.restrict) { sql += " AND cd.restriction = 1"; # Of Alternatives = 2 } sql += " AND cd.id =?"; # Unknown Parts = 1 PreparedStatement s = this.con.preparestatement(sql); % syntactically Correct Alt. s.setint(1, id); = 100% ResultSet rs = s.executequery(); rs.next(); Determine starting point return rs.getint( credit"); Slicing to determine fragment } Starting point Compute metrics PAGE 20

21 Java: limitations on analysis Analysis limited to methods Only interpretation of: String StringBuilder StringBuffer Numeric types Decisions regarded as non-deterministic More/less alternatives found than possible PAGE 21

22 Java: case studies ERP system GPL license Company-maintained, little community feedback used 0.7 million lines of code 2056 DB calls detected ERP system GPL license Community-driven fork of Compiere 1.1 million lines of code 2631 DB calls detected DJI GUI-based interview appl. 2 students assistants, 1 month 12,600 lines of code PAGE 22

23 Compiere results: categorization 12% 6% % Known value Decisions Unknown parts Both 67% Queries categorized by complexity PAGE 23

24 Compiere results: parsability Statements detected parsed Cat. 1 Cat. 2 Cat. 3 Cat. 4 Total PAGE 24

25 Compiere: parse errors Analysis errors: 54 Incomplete SQL parser: 5 Syntax errors: 8 String sql = "SELECT * " + "FROM tablex " + "WHERE value IS NOT NULL" + "ORDER BY value"; stmt.executequery(sql); PAGE 25

26 Compiere: quality metrics Java SQL PAGE 26

27 Compiere: Dependencies Global dependencies PAGE 27

28 Compiere: Dependencies Database dependencies PAGE 28

29 Code duplication between files Compiere Adempiere PAGE 29

30 Code duplication: DB error handling Compiere Adempiere PAGE 30

31 Case study: DJI GUI-based interview application 2 student assistants, 1 month 12,600 lines of code Prototype PAGE 31

32 DJI: Dependencies Internal dependencies PAGE 32

33 DJI: GUI & DB dependencies GUI Database PAGE 33

34 Conclusions Analysis of embedded languages can be done Tools need optimizations for optimal results Useful: results give insight in structure Assessment is a man's job No 100% analysis possible PAGE 34

35 Conclusions: answer 1 How can the combination of embedded language fragments and host language statements be analyzed? Language dependent: COBOL: recognize extended language Java: interpret language No generic approach, each language needs specialized tools PAGE 35

36 Conclusions: answer 2 When analyzing embedded language fragments and host language statements, can relevant metrics be calculated and dependencies be analyzed? Complexity of embedded code Interaction between host- and guest-language Dependencies between host-language and database Relevant insight PAGE 36

37 Current work: Evolution Compiere and Adempiere compared over time Compiere: 5 versions between 2006 and 2008 Adempiere: 16 versions between 2006 and nov 2009 Gain confidence in proposed interaction metrics 2008 lucdgbxl@flickr PAGE 37

38 Evolution: Categories 2056 fragments 2631 fragments PAGE 38

39 Evolution: outcome Analysis of either Java or SQL not enough Categorization distinguishes case studies Using this: Insight in evolution of case studies Insight in complexity of case studies PAGE 39

40 Current work: Hibernate Analysis of Hibernate categorization performed 3 days to make modifications Vast differences between 3 case studies Compared by files using DB system: Plazma OpenPM OpenBravo JDBC SQLC Hibernate PAGE 40

41 Future work Validation of metrics Analysis of C#/Ado.NET PAGE 41

42 Questions? SQL PAGE 42