FSE '21 paper implementation (preprint)
DOI of submitted version executable file of NIL is 10.5281/zenodo.4492665.

NIL

NIL is a clone detector using N-gram, Inverted index, and LCS. NIL provides scalable large-variance clone detection.

Requirements

• JDK 21+

Install & Usage

• Clone this repository (git clone https://github.com/kusumotolab/NIL)
• Move into NIL's directory (cd NIL) and build NIL (./gradlew ShadowJar)
• Run NIL (java -jar ./build/libs/NIL-all.jar [options])
• Check the result file
  • If you didn't specify -bce option, the format is /path/to/file_A,start_line_A,end_line_A,/path/to/file_B,start_line_B,end_line_B.
  • If you specified -bce option, the format is dir_A,file_A,start_line_A,end_line_A,dir_B,file_B,start_line_B,end_line_B

Options

Name	Description	Default
-s,--src	Input source directory. You must specify the target dir.	None
-mil,--min-line	Minimum number of lines that a code fragment must be to be treated as a clone.	6
-mit,--min-token	Minimum number of tokens that a code fragment must be to be treated as a clone.	50
-n,--n-gram	N for N-gram.	5
-p,--partition-size	The number of partitions.	10
-f,--filtration-threshold	Threshold used in the filtration phase (%).	10
-v,--verification-threshold	Threshold used in the verificatioin phase (%).	70
-o,--output	Output file name.	result_{n}_{f}_{v}.csv
-t,--threads	The number of threads used for parallel execution (both the Preprocess and Clone detection phases)	all threads
-l,--language	Target language	java
-bce,--bigcloneeval	If you specify -bce option, NIL outputs result file feasible to BigCloneEval.	not specified
-mif,--mutationinjectionframework	If you specify -mif option, NIL outputs nothing except for the output file name as standard output.	not specified

Languages

Name	Option	Extension
Java	java	.java
C	c	.c,.h
C++	cpp	.cpp,.hpp
C#	cs,csharp	.cs
Python	py,python	.py
Kotlin	kt,kotlin	.kt

If you execute NIL on 250-MLOC codebase, we recommend -p option to 135.

Experiments, datasets, and baseline tools

• Please refer to EXPERIMENTS.md