Java Random Access File Stream Manager

A desktop application built in Java featuring dual Swing GUIs for generating, persisting, and searching fixed-width binary records using RandomAccessFile streams.

📌 Overview

This project demonstrates binary file stream operations and low-level data persistence in Java. By enforcing fixed-length character padding across string fields, the system achieves predictable byte-length records (240 bytes per record), enabling efficient non-sequential file positioning, record creation, input validation, and partial-text search querying.

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✨ Key Features

• Fixed-Width Binary Sizing: Pads string attributes with trailing spaces to ensure constant 240-byte record lengths for direct byte-level offset positioning.
• Record Entry GUI (RandProductMaker): Form-driven interface with input validation, real-time record counting, and appended binary file storage.
• Search GUI (RandProductSearch): Real-time search tool that scans binary records and returns matching products based on partial string queries.
• Robust Validation: Safeguards against empty inputs and invalid data types before performing disk writes.

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🛠️ Data Model Sizing Architecture

Field	Data Type	Character Limit	Encoding Sizing	Byte Size
ID	String	6 chars	2 bytes / char	12 bytes
Name	String	35 chars	2 bytes / char	70 bytes
Description	String	75 chars	2 bytes / char	150 bytes
Cost	Double	N/A	8-byte IEEE 754	8 bytes
Total Record Size				240 Bytes

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📁 Repository Structure

src/
├── Product.java              # Data model & fixed-width padding logic
├── RandProductMaker.java     # Entry GUI for saving binary records
└── RandProductSearch.java    # Search GUI for querying binary records
README.md

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🚀 How to Run

Prerequisites

• Java Development Kit (JDK 17 or higher)
• Java IDE (IntelliJ IDEA, Eclipse, or VS Code)

Execution Steps

1. Clone the repository:

   git clone https://github.com/deshyah/java-random-access-file-manager.git

2. Open the project in your Java IDE.

3. Run RandProductMaker.java to enter product records and create the ProductData.dat file.

4. Run RandProductSearch.java to search records in ProductData.dat.

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💡 Key Engineering Takeaways

• Constant-Time Positioning: Fixed record lengths enable $O(1)$ lookup positioning via offset calculations ($\text{offset} = \text{index} \times 240$) using RandomAccessFile.seek().
• Binary Stream Overhead: Storing structured binary data avoids text-parsing overhead and ensures strict layout control on disk.
• Field Normalization: Utility padding methods handle string truncation and space padding before writing data to the binary stream.