PDF Generator Project

📋 Project Overview

Project Title: PDF Generator Tool
Description: A Java-based application that converts text files and images to PDF format, demonstrating core Object-Oriented Programming concepts including inheritance, polymorphism, abstraction, and encapsulation.

Key Features:

• Convert text files to properly formatted PDF documents
• Convert images to PDF with embedded image information
• Interactive console-based user interface
• Proper PDF file generation that works with standard PDF viewers
• Educational demonstration of OOP principles

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🏗️ Project Structure

Java Project/
├── src/
│   └── com/
│       └── pdfgenerator/
│           ├── PDFGenerator.java          # Abstract base class
│           ├── TextToPDFGenerator.java    # Text to PDF converter
│           ├── ImageToPDFGenerator.java   # Image to PDF converter
│           └── PDFGeneratorApp.java       # Main application class
├── sample-files/
│   ├── sample.txt                         # Sample text for testing
│   └── README_for_images.txt             # Instructions for image files
├── output/                               # Generated PDF files appear here
├── lib/                                  # (Reserved for future libraries)
├── README.md                            # This file
├── VIVA_PREPARATION.md                  # Detailed viva preparation guide
└── COMPILE_AND_RUN.md                   # Step-by-step execution guide

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🎯 Object-Oriented Programming Concepts Demonstrated

1. Inheritance

• PDFGenerator serves as the abstract parent class
• TextToPDFGenerator and ImageToPDFGenerator extend the base class
• Child classes inherit common methods like validateInputFile() and status display methods
• Demonstrates "IS-A" relationship (TextToPDFGenerator IS-A PDFGenerator)

2. Polymorphism

• Same method generatePDF() behaves differently in each subclass
• PDFGenerator reference can point to any concrete implementation
• Runtime method resolution based on actual object type
• Demonstrates method overriding and dynamic binding

3. Abstraction

• PDFGenerator contains abstract method generatePDF()
• Hides implementation details from user
• Provides clean interface for PDF generation
• Each subclass must implement the abstract method

4. Encapsulation

• Private methods for internal PDF creation logic
• Protected fields accessible only to subclasses
• Public methods provide controlled access to functionality
• Data hiding and access control principles

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🚀 How to Compile and Run

Prerequisites

• Java Development Kit (JDK) 8 or higher
• Windows Command Prompt or PowerShell
• Text editor (VS Code, Notepad++, etc.) for viewing files

Step 1: Navigate to Project Directory

cd "C:\Users\HP\Downloads\Java Project"

Step 2: Compile All Java Files

javac -cp . src\com\pdfgenerator\*.java -d .

What this does:

• javac: Java compiler command
• -cp .: Sets classpath to current directory
• src\com\pdfgenerator\*.java: Compile all Java files in package
• -d .: Output compiled classes to current directory

Step 3: Run the Application

java com.pdfgenerator.PDFGeneratorApp

Step 4: Use the Application

You'll see a menu like this:

========================================
    Welcome to PDF Generator Tool
========================================

╔══════════════════════════════════════╗
║            MAIN MENU                 ║
╠══════════════════════════════════════╣
║ 1. Convert Text File to PDF         ║
║ 2. Convert Image File to PDF        ║
║ 3. Demo with Sample Files           ║
║ 4. View Output Directory            ║
║ 5. Exit                             ║
╚══════════════════════════════════════╝
Enter your choice (1-5):

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📝 Usage Examples

Option 1: Convert Text File to PDF

1. Choose option 1
2. Enter path: sample-files\sample.txt
3. PDF will be generated in output/ folder

Option 2: Convert Image to PDF

1. Add an image file (JPG/PNG) to sample-files/ folder
2. Choose option 2
3. Enter the image file path
4. PDF with image information will be created

Option 3: Run Demo (Recommended for Testing)

1. Choose option 3
2. Automatically processes sample files
3. Shows both text and image conversion

Option 4: View Generated Files

1. Choose option 4
2. See list of all generated PDF files
3. File sizes and names displayed

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🔧 Technical Implementation Details

PDF File Structure Created

Our application generates proper PDF files with:

1. PDF Header: %PDF-1.4 (version identifier)
2. Binary Marker: Ensures compatibility with PDF readers
3. Object Catalog: Root object defining document structure
4. Pages Object: Container for all pages in document
5. Page Object: Individual page with dimensions and content
6. Font Object: Text rendering font (Helvetica)
7. Content Stream: Actual text/image content data
8. Cross-Reference Table: File navigation information
9. Trailer: Document metadata and structure
10. End Marker: %%EOF (end of file)

Text Processing Features

• Line Wrapping: Automatically wraps long lines to fit page width
• Character Escaping: Handles special PDF characters safely
• Font Formatting: Uses standard Helvetica font at 12pt
• Margin Control: 50-point margins on all sides
• Multi-line Support: Processes line breaks correctly

Image Processing Features

• Format Support: JPG, PNG, GIF, BMP image files
• Scaling Calculation: Automatically scales images to fit A4 page
• Aspect Ratio: Maintains original image proportions
• Positioning: Centers images on PDF page
• Metadata: Includes original dimensions and file information

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📚 File I/O Operations Demonstrated

Input Operations

• BufferedReader: Efficient text file reading
• FileReader: Character stream reading
• ImageIO: Image file loading and processing
• File Validation: Existence and readability checks

Output Operations

• FileOutputStream: Binary PDF file writing
• BufferedWriter: Efficient text output
• OutputStreamWriter: Character encoding control
• Directory Management: Automatic folder creation

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🎓 Educational Value

Perfect for Academic Demonstration

• Real-World Application: Solves actual problem (file conversion)
• Industry Relevance: PDF generation is common in enterprise applications
• Scalable Design: Easy to extend with additional features
• Clean Code: Well-commented and organized for learning

Concepts Suitable for Examination

• Object-oriented design principles
• File handling and I/O operations
• Exception handling and error management
• User interface design (console-based)
• Software architecture and modularity

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🔍 Troubleshooting

Compilation Issues

Problem: javac not recognized
Solution: Ensure JDK is installed and added to PATH

Problem: Class not found errors
Solution: Make sure you're in the project root directory

Runtime Issues

Problem: File not found when converting
Solution: Use absolute paths or ensure files exist in specified location

Problem: Permission denied creating output
Solution: Check write permissions on output directory

PDF Viewing Issues

Problem: Generated PDF won't open
Solution: Try different PDF viewer (Adobe Reader, browser, etc.)

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🚀 Future Enhancements

Possible Extensions

1. GUI Interface: Swing or JavaFX-based user interface
2. iText Integration: Professional PDF library for advanced features
3. Multi-page Support: Handle documents longer than one page
4. Image Embedding: True image data embedding in PDF
5. Font Options: Multiple font types and sizes
6. Batch Processing: Convert multiple files simultaneously
7. PDF Merging: Combine multiple PDFs into one
8. Encryption: Password protection for generated PDFs

Production Considerations

• Use established libraries (iText, Apache PDFBox) for commercial use
• Add comprehensive error handling and logging
• Implement unit tests for all components
• Add configuration files for customization
• Consider memory optimization for large files

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📞 Support and Documentation

For questions about this project:

1. Review the VIVA_PREPARATION.md file for detailed examination guidance
2. Check COMPILE_AND_RUN.md for step-by-step execution instructions
3. Examine source code comments for implementation details
4. Test with sample files to understand functionality

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📄 License and Usage

This project is created for educational purposes and academic demonstration. Feel free to use, modify, and extend for learning objectives.

Created: October 2025
Language: Java 8+
Platform: Cross-platform (Windows, Mac, Linux)
Dependencies: Standard Java libraries only

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Happy coding and good luck with your viva examination! 🎉