File Compression and Decompression with Deflate Algorithm

This Java project implements file compression and decompression using the Deflate algorithm, which combines LZ77 and Huffman coding techniques. The program offers a command-line interface for compressing, decompressing, comparing file sizes, and checking if two files are equal.

Features

• Compression (comp): Compresses a given source file and outputs the result to an archive.
• Decompression (decomp): Decompresses a given archive and outputs the result to a specified file.
• Size Comparison (size): Displays the size of a specified file in bytes.
• File Equality Check (equal): Checks if two files are identical.
• About Information (about): Displays information about the developer.

Results

File name	File size (KB)	Comp. file size (KB)	Comp. ratio	Comp. coef.	Comp. time (ms)	Decomp. time (ms)
Java.html	80.479	33.356	58.55 %	2.41	663	67
JavaScript.html	344.523	107.19	68.89 %	3.21	2544	64
RTU.html	83.069	30.93	62.77 %	2.69	518	14
Rainis.html	206.694	57.458	72.20 %	3.60	1321	17
MonteCarlo.html	612.88	100.359	83.63 %	6.11	2331	23

Included Files

Along with Main.java, the repository contains an examples folder with the following files:

• Java.html
• JavaScript.html
• RTU.html
• Rainis.html
• MonteCarlo.html

These files can be used to test and demonstrate the functionality of the compression and decompression features.

Usage Examples

The following examples demonstrate some of the available commands:

• Compression:
  • Input: comp
  • Prompts:
    • "source file name:" (e.g., File1.html)
    • "archive name:" (e.g., File1.compressed)
  • Description: Compresses File1.html and stores the compressed data in File1.compressed.
• Decompression:
  • Input: decomp
  • Prompts:
    • "archive name:" (e.g., File1.compressed)
    • "file name:" (e.g., DecompressedFile1.html)
  • Description: Decompresses File1.compressed and stores the decompressed content in DecompressedFile1.html.
• Size Comparison:
  • Input: size
  • Prompts:
    • "file name:" (e.g., File1.html)
  • Description: Displays the size of File1.html in bytes.
• File Equality Check:
  • Input: equal
  • Prompts:
    • "first file name:" (e.g., File1.html)
    • "second file name:" (e.g., DecompressedFile1.html)
  • Description: Checks if File1.html and DecompressedFile1.html are identical.
• About Information:
  • Input: about
  • Description: Displays information about the developer.

Credits

This project was developed by Daniels Stulpe, a student at Riga Technical University.