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This research focuses on automatically detecting and describing high-level actions within methods by analyzing code fragments and expressing them in natural language. Techniques include syntax tree analysis, linguistic knowledge, and SWUM word usage. Challenges arise in integrating similar statements, abstracting conditionals, and identifying loops. Evaluations show significant reductions in identified high-level actions with improved precision.
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Automatically detecting and describing high level actions within methods Presented by: GayaniSamaraweera
The problem • Given signature and the body of a method M, automatically discover each code fragment that implements a high level action comprising the overall algorithm of M, and accurately express each high level action as a succinct natural language description
Outline • The problem • Outline • High level actions • Method • Evaluation • Concerns • Other uses • Conclusion
High level actions • Sequence fragment • A sequence of statements that when taken together represents a single high level action • Conditional fragment • A conditional block that performs an action with subtle variations based on the condition • Loop fragment • Code patterns that are commonly implemented using loop constructs that constitute a high level action
Detecting high level actions • Uses • AST (Abstract Syntax Tree) • CFG (Control Flow Gragh) • Information from naming conventions and linguistic knowledge gained from observations of Java programs • Textual clues from SWUM (Software Word Usage Model)
cont.. • Word usage information from identifiers • Identifier splitting • Camel case splitting: on capital letters, underscores, numbers • Eg: childXMLElement → child XML Element • Expand identifier abbreviations • Eg: Button butSelectAll, MouseEvent evt • SWUM → action, theme, optional secondary arguments of a statement grouping • Eg: list.add(Item i); → “additemto list” action secondary argument theme
Sequence as single action • Sequence fragments • Identifying sequences of statements with similar actions • Indicated by similar method calls
cont.. • Challenges • Integrate to successor statement based on similarity • Different method names • Same method name different parameter types
cont.. • Identifying fragments • Statements with one or more method calls Add ended panel to content panel Add bid panel to content panel Verb → add → equals Head word of NP → panel → equals Preposition → to content panel → equals → integratable
cont.. • Synthesizing descriptions • If equal head word → plural • Else Add okButton to content panel Head word of NP → different But if fields of same class → “all attributes” “different attributes”
Abstracting conditionals • Challenges • Integrating similar statements in different branches • Integrating conditional statements guarding different branches • Integrating return statements with literals or similar method calls
cont.. • Identifying and describing conditionals • Integrate statements of each block, compare each statement with statements of parent block • For method calls Singular
cont.. • For return statements • For assignment statements Theme based on enclosing method Update, create or get
cont.. • Describing conditional expressions • Compare phrases as 'subject predicate object' • Subject and predicate are equal → based on what <subject> <predicate> Based on what os name starts with If only head word of subject is equal Based on which <head word> <predicate> <object> Based on which radio button is selected
Finding traceable patterns in loops • Challenges • Common algorithms as finding, counting, copying • Develop identification templates • Develop heuristics to synthesize phrases for each template
cont.. • Loop abstractions implemented • Count • Contains • Find • Copy • Max-min
cont.. • Identifying fragments and synthesize templates
cont.. • Variations in synthesis templates • 'find item (in collection) whose/which/such that <criteria>' in subject predicate object, • If item is subject → which • If an attribute of item is subject → whose • Default → such that
Evaluation • Executed on 1.2 million methods across 1000 Java programs
cont.. • How prevalent are the implemented high level methods? • Sequence (methods with >= 10 statements 12.5%) • 11% • Conditional • 40% of if-else • 24% of switch • Loop • 51% of loops classified as iterating over all items in a collection • 15% of iteratorloops detected by implemented patterns
cont.. • Potential reduction in reading detail • Reduction in identified high level actions • Sequence → one phrase • 22% of original size • Conditional → two phrases • 29% of original size • Loop → varying # phrases • 25% of original size
cont.. • Precision of identification and description • 15 human evaluators, each evaluating 15 code fragments (5-sequence, 5-conditional, 5-loop) • 75 code fragments from 15 projects evaluated by 3 evaluators From methods with <= 20 statements 25-conditional, 25-sequence, 25-loop Loops: 5 fragments from each 5 patterns
cont.. • Evaluators wrote an abstraction of the method • Answered following based on 1 – strongly disagree to 5 – strongly agree identification description
cont.. Majority agreed or strongly agreed on both P1 and P2
Concerns.. • May not generalize to other Java programs • Results may vary on larger programs • Results might not hold with novices • Reduction in reading measurement may not hold with some developers
Improving client tools • Extract method refactoring Create application based on what os starts with Set different attributes of SVGApplicationModel
cont.. • Internal comment generation • Instead of Extract Method refactoring, can add comments inline • Add empty lines between related code fragments • Suggesting more informative method names • Improving automatically generated summary comments for a method
Conclusions • First technique for identifying code fragments of statement sequences, conditionals and loops, that is abstracted to a high level action • Automatically synthesizing natural language description
References • GiriprasadSridhara, Lori Pollock, and K. Vijay-Shanker. Automatically detecting and describing high level actions within methods. In Proceeding of the 33rd international conference on Software engineering (ICSE '11). ACM, New York, NY, USA, 101-110. • G. Sridhara, E. Hill, D. Muppaneni, L. Pollock, and K. Vijay-Shanker. Towards Automatically Generating Summary Comments for Java Methods. Intl. Conf on Automated Softw. Engg. (ASE’10), 2010. • GiriprasadSridhara, Lori Pollock, K. Vijay-Shanker, "Generating Parameter Comments and Integrating with Method Summaries," International Conference on Program Comprehension, pp. 71-80, 2011 IEEE 19th International Conference on Program Comprehension, 2011 • E. Hill. Integrating Natural Language and Program Structure Information to Improve Software Search and Exploration. PhD Dissertation, University of Delaware, 2010.