Unique IPv4 Address Counter

This Java project efficiently counts the number of unique IPv4 addresses from a large input file using low memory and high performance techniques. It's built to scale to files containing tens or hundreds of gigabytes of IP data.

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🚀 Features

• Processes unlimited size files line-by-line using Java Streams
• Custom IP address to int converter (IPToIntConvertor)
• Efficient deduplication using a memory-optimized BitSetContainer
• Uses only Java standard library (no external dependencies)
• IP addresses are stored as 32-bit signed integers (int)
• Supports reading input file from classpath via ClassLoader

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📂 Project Structure

src
└── main
├── java
│   └── com
│       └── guseyn
│           ├── App.java # Entry point: counts unique IPv4 addresses using classloader
│           ├── BitSetContainer.java  # Efficient int container using BitSet array for deduplication
│           ├── IntContainer.java  # Interface for custom integer containers
│           ├── IpWriter.java # Fast, memory-efficient converter from IPv4 string to int
│           └── IPToIntConverter.java
└── resources
└── ips.txt # Input file containing IPv4 addresses, one per line

Usage

• Run IpWriter to generate your list of IPv4 addresses in the file: src/main/resources/ips.txt (One IP address per line, e.g., 192.168.1.1) or place your file.
• Run App to get unique number of IP addresses.

Shout-out

Main principals are learnt from the article written by Jegors Čemisovs: https://jc.id.lv/posts/counting-unique-ipv4-addresses/