Duplicate Files Finder
The task is to implement program that will find duplicate files in specified directory and allow users to perform various operation on them.
Supported operations
- Delete files.
- Create hard link: https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/nio/file/Files.html#createLink(java.nio.file.Path,java.nio.file.Path)
- Create soft link: https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/nio/file/Files.html#createSymbolicLink(java.nio.file.Path,java.nio.file.Path,java.nio.file.attribute.FileAttribute...)
How to find duplicate files
-
For each file compute its hash by using https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/security/MessageDigest.html (https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/security/DigestInputStream.html might be useful). Optionally you can create your own hashing implementation.
-
If two files have the same hash then compare their content byte by byte.
Program input
Program receives paths to directories in which it is supposed to find duplicate files as
program arguments. That means they are in String[] args variable of the main method.
Program will be called in the following manner:
java package.YourMainClass ${dir1} ${dir2}Interactive mode
Upon finding a duplicate, program will present user with following output:
Found duplicate files:
0. ${f1}
1. ${f2}
2. ${f3}
…
What do you want to do? (0 = ignore, 1 = delete, 2 = create soft link, 3 = create hard link)
Delete (1)
Your program output:
Do you want to delete ${f}? (y/n)
Create soft link (2)
Keeps only one file and others will be replaced with soft links.
File for which to create soft link: (file number)
Create hard link (3)
Keeps only one file and others will be replaced with hard links.
File for which to create hard link: (file number)
Test files
Simple Test
Expected output:
Found duplicate files:
0. test1
1. test2
What do you want to do? (0 = ignore, 1 = delete, 2 = create soft link, 3 = create hard link)
…
Complex Test
Expected output:
Found duplicate files:
0. bin/bin4
1. bin/bin6
What do you want to do? (0 = ignore, 1 = delete, 2 = create soft link, 3 = create hard link)
…
Found duplicate files:
0. src/main/java/cz/cuni/mff/HelloWord.java
1. test/reources/test_input.txt
2. test/reources/test_input.txt2
What do you want to do? (0 = ignore, 1 = delete, 2 = create soft link, 3 = create hard link)
…
Good luck :)