DOI: 10.5281/zenodo.12905296
title: Impact of Methodological Choices on the Analysis of Code Metrics and Maintenance

description: The repo-data folder contains 53 .json files, each corresponding to one of the 53 Java open-source projects. Each file contains various metrics for methods in the project.

 

 {
        "hawtio-3976.json": {
            "Age": 794,
            "sloc": [11,11,11],
            "slocAsItIs": [11,14,14],
            "slocNoCommentPretty": [11,11,11],
            "diffSizes": [0,7,0 ],
            "bodychanges": [0,1,0], 
            "newAdditions": [0,5,0],
            "isGetter": [false,false,false],
            "isSetter": [false,false,false],
            "changeDates": [0,3,794],
            "isEssentialChange": [false,true,false],
            "isBuggy": [false,false,false],
            "changeTypes": ["Yintroduced","Ybodychange","Yfilerename"],
            "filename": "hawtio-3976.json",
            "authors": ["X","Y","Z"],
            "editDistance": [0, 68, 0],
            "repo": "hawtio"
        },
        "method_id": {...},
        "method_id": {...}
    }


 

The above method with id hawtio-3976.json has total 3 revisions which is why the array of values for a particular metric (e.g., sloc: [11,11,11]) are of length 3. Index 0 of the array represents the introduction value of a particular metric for the above method.



Description of the metrics




Age: Age of the method in days

sloc: Source line of code of a method without comment and blank lines

slocAsItIs: Source line of code of a method with comment and blank lines

slocNoCommentPretty: Source line of code pretty printed without comment and blank lines

diffSizes: Total number of lines added + removed in git diff

bodychanges: Contains value 0 or 1; where 1 implies occurrence of body change

newAdditions: Total number of lines added in git diff

isGetter: Contains true or false; where true indicates it is a get method

isSetter: Contains true or false; where true indicates it is a set method

changeDates: Contains the date difference in days from when the method was introduced. Index 0 is always 0 which indicates the introduction date

isEssentialChange: Contains true or false; where true indicates it is an essential change. Essential change includes: Ybodychange, Ymodifierchange, Yexceptionschange, Yrename, Yparameterchange, Yreturntypechange and Yparametermetachange detected by CodeShovel

isBuggy: Contains true or false; where true indicates the method bug was fixed at a particular revision

changeTypes: All transformations applied to the method at each revision. The full list of transformation that is detected by CodeShovel are: Ybodychange, Ymodifierchange, Yexceptionschange, Yrename, Yparameterchange, Yreturntypechange, Yparametermetachange, Yannotationchange, Ydocchange, Yformatchange, Yfilerename and Ymovefromfile

filename: It is the method id

bugData folder contains 53 .json files with bug information, each belonging to one of the 53 Java open-source projects. The sample JSON schema of a file is given below:

{
    "hawtio-3976.json":{
        "exactBug0Match": [false, false, false],
        "exactBug1Match": [false, false, false],
        "exactBug2Match": [false, false, false],
        "exactBug3Match": [false, false, false],
        "regExBug0": [false, false, false],
        "regExBug1": [false, false, false],
        "regExBug2": [false, false, false],
        "regExBug3": [false, false, false]
    },
    "method_id": {...},
    "method_id": {...},
}

The above method can be mapped to its metrics dataset using the method_id. For e.g., the above method with id hawtio-3976.json in bugData/hawtio.jsonthat has 3 revision can be found in the metric dataset using the same id hawtio-3976.json in the file repo-data/hawtio.json.Description of bug dataset

Each key in the above example contains value true or false indicating if a method was buggy or not at each revision. The "hawtio-3976.json method has 3 revisions (including method's introduction) which is why the array length is 3. The keys in the above json output represent bug-fix classification based on buggy keywords adopted from prior work.

We identified bug-fix commit using two approaches:

    Exact case insensitive match of buggy keywords from the commit message (keys prefix wih exact represent this)    Partial case insensitive substring match (using regular expression) excluding words that ends with fix or bug. (keys prefix with regEx represent this)

    Bug0: This is the approach that we have used for classifying bug-fix commit. Buggy keyword list: ["error", "bug", "fixes", "fixing", "fix", "fixed", "mistake", "incorrect", "fault", "defect", "flaw"]    Bug1: Same keyword list as exactBug0Match with the addition of keyword issues    Bug2: Buggy keyword list from prior work: ["bug", "fix", "error", "issue", "crash", "problem", "fail", "defect", "patch"]    Bug3: Buggy keyword list from prior work: ["error", "bug", "fix", "issue", "mistake", "incorrect", "fault", "defect", "flaw", "type"]