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 , and by Quanta Computer as part of the TParty project.

Keyword Programming

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

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

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

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

read a line from src, and add it to array

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

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

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

read a line from src, and add it to array

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

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

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

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

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

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

Motivation

Overview Algorithm Evaluation

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

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

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

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

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

Algorithm Function Database Dynamic Program Extract Tree

Function Database array List

Function Database array List add boolean List, String

Function Database array List add boolean List, String src BufferedReader

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Results overall 91%

Results under 500ms

Results

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: about 70% students 3 females

User Study

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

Results Algorithm as-is

Results javakey/pseudo usingas-is using algorithm

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

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

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

Future Work synonyms lowercase toLowerCase add vs append spell correction

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

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