1. Keyword Programming in Java Greg Little and Robert C. Miller MIT CSAIL This work was supported in part by the National Science Foundation under award number IIS-0447800, and by Quanta Computer as part of the TParty project.

2. Keyword Programming

3. Problem src read a line from src, and add it to array array cursor

4. AutoComplete read a line from src, and add it to array

5. AutoComplete read a line from src, and add it to array

6. read a line from src, and add it to array AutoComplete

7. read a line from src, and add it to array

8. AutoComplete read a line from src, and add it to array

9. read a line from src, and add it to array AutoComplete

10. read a line from src, and add it to array AutoComplete

11. read a line from src, and add it to array

12. Keyword Programming read a line from src, and add it to array

13. Keyword Programming read a line from src, and add it to array

14. Keyword Programming read a line from src, and add it to array

15. Keyword Programming read a line from src, and add it to array

16. Keyword Programming read a line from src, and add it to array

17. Related Work AutoComplete syntactically valid prefix Jungloids [Mandelin et al PLDI ’05] XSnippet [Sahavechaphan et al OOPSLA ’06] input and output types Keyword Programming keywords from expression

18. Motivation

19. Overview Algorithm Evaluation

20. Algorithm array.add(src.readLine());

21. array.add(src.readLine); array readLine src Algorithm

22. array.add(src.readLine); array readLine src Algorithm BufferedReader StringList

23. array List readLine String BufferedReader src BufferedReader add boolean List, String Algorithm

24. array List readLine String BufferedReader src BufferedReader add boolean List, String Algorithm Function

25. Algorithm Function Database Dynamic Program Extract Tree

26. Function Database array List

27. Function Database array List add boolean List, String

28. Function Database array List add boolean List, String src BufferedReader

29. List Functions array List add boolean List, String src BufferedReader readLine String BufferedReader

30. Function Database array List add boolean List, String src BufferedReader readLine String BufferedReader new String String

31. Score Functions array List add boolean List, String src BufferedReader readLine String BufferedReader new String String

32. Score Functions array List add boolean List, String src BufferedReader readLine String BufferedReader new String String add line

33. 1 Score Functions array List add boolean List, String src BufferedReader readLine String BufferedReader new String String add line

34. Score Functions array List add boolean List, String src BufferedReader readLine String BufferedReader new String String add line 11

35. Dynamic Program List BufferedReaderString List booleanBufferedReaderString List booleanBufferedReaderString add List, String srcreadLine BufferedReader arrayadd List, String readLine BufferedReader array boolean array src new String src ? array List add boolean List, String src BufferedReader readLine String BufferedReader new String String 11 add List, String 1 1 1 1 1 11 1 2 1

36. Extract Tree List BufferedReaderString List booleanBufferedReaderString List booleanBufferedReaderString add List, String srcreadLine BufferedReader arrayadd List, String readLine BufferedReader array src new String src 1 2

37. Extract Tree List BufferedReaderString List booleanBufferedReaderString List booleanBufferedReaderString add List, String srcreadLine BufferedReader arrayadd List, String readLine BufferedReader array src new String src 1 2

38. Extract Tree List BufferedReaderString List booleanBufferedReaderString List booleanBufferedReaderString add List, String srcreadLine BufferedReader arrayadd List, String readLine BufferedReader array src new String src 1 2

39. Extract Tree List BufferedReaderString List booleanBufferedReaderString List booleanBufferedReaderString add List, String srcreadLine BufferedReader arrayadd List, String readLine BufferedReader array src new String src 1 2

40. Extract Tree BufferedReader add List, String arrayreadLine BufferedReader src List String boolean

41. Render as Java BufferedReader add List, String arrayreadLine BufferedReader src List String boolean array.add(src.readLine())

42. More Complex.Math.max(x, y).......... Keep best n functions per box max x y..Math.max(x, x).......... 3 Discourage double counting

43. Artificial Corpus sense of speed in real projects sense of accuracy in wide variety of contexts User Study sense of accuracy on real inputs sense for how real inputs look Evaluation

44. Artificial Corpus Azureus340 kloc Buddi28 kloc CAROL18 kloc Dnsjava17 kloc Jakarta CC10 kloc jEdit125 kloc jMemorize15 kloc Jmol88 kloc JRuby72 kloc Radeox71 kloc RSSOwl71 kloc Sphinx67 kloc TV-Browser120 kloc Zimbra256 kloc multiple open source repositories Popular Could Compile

45. Artificial Corpus Azureus340 kloc Buddi28 kloc CAROL18 kloc Dnsjava17 kloc Jakarta CC10 kloc jEdit125 kloc jMemorize15 kloc Jmol88 kloc JRuby72 kloc Radeox71 kloc RSSOwl71 kloc Sphinx67 kloc TV-Browser120 kloc Zimbra256 kloc

46. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name)

47. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) RubySymbol newSymbol getRuntime name

48. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) RubySymbol newSymbol getRuntime name

49. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) RubySymbol newSymbol getRuntime name ruby symbol new symbol get runtime name

50. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) RubySymbol newSymbol getRuntime name ruby symbol new symbol get runtime name name runtime get symbol symbol ruby new

51. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) name runtime get symbol symbol ruby new

52. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) name runtime get symbol symbol ruby new Algorithm

53. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) Algorithm name runtime get symbol symbol ruby new

54. Artificial Corpus RubySymbol.newSymbol(getRuntime(), name) Algorithm Record: - match? - how long? - how many keywords? Record: - match? - how long? - how many keywords? name runtime get symbol symbol ruby new

55. Results overall 91%

56. Results under 500ms

57. Results

59. User Study solicited experienced Java programmers (from college mailing lists) motivated with money —chance to win $20 web based study good data for 49 participants ages: 18 - 74 about 70% students 3 females

60. User Study

62. Results Algorithm as-is CorrectIncorrect vowels.indexOf(c)vowels.index(c) vowels.isIn(c) index of c in vowelscheck vowels for c, return neg -1 if c is in vowels vowels search csearch vowels.charAt(c) vowels.indexOf(c,Integer.SIZE)) c

63. Results Algorithm as-is

64. Results javakey/pseudo usingas-is using algorithm

65. Results javakey/pseudo usingas-is53% using algorithm71%53%

66. Future Work print name of f Integer.valueOf(f.getName()) System.out.print(f.getName()) a priori word weights becomes want of f name print f name 1 1 1 3 1 1 1 3

67. Future Work println f name System.err.println(f.getName()) System.out.println(f.getName()) a priori function weights becomes want println f name 1 1 1 3 println f name 1 1 1 3

68. Future Work synonyms lowercase toLowerCase add vs append spell correction

69. Conclusion array.add(src.readLine());

70. Backup Slides 70

71. E-mail glittle@gmail.com