PDF Editor

A Spring Boot application for processing and editing PDF documents with support for form fields, placeholders, text fields, and signature fields.

Features

• Placeholder Replacement - Replace {{placeholder}} text in PDFs with custom values
• Form Field Filling - Fill existing AcroForm fields in PDF documents
• Text Field Creation - Add new interactive text fields at specific coordinates
• Signature Field Creation - Add signature fields for digital signing
• PDF Flattening - Flatten filled PDFs to make them non-editable
• Single PDF Processing - Process one PDF at a time via REST API or web interface
• Batch Processing - Process multiple PDFs asynchronously
• Swagger Documentation - Interactive API documentation available

Technology Stack

• Framework: Spring Boot 3.4.0
• Java Version: 21
• PDF Library: Apache PDFBox 2.0.30
• API Documentation: SpringDoc OpenAPI 2.6.0
• JSON Processing: Jackson
• Build Tool: Maven

Quick Start

Prerequisites

• Java 21 or higher
• Maven 3.6+

Build and Run

# Build the application
./mvnw clean package -DskipTests

# Run the application
./mvnw spring-boot:run

The application will start on http://localhost:8080

Using the Web Interface

1. Open http://localhost:8080 in your browser
2. Upload a PDF file
3. Configure placeholders, text fields, signature fields, or form fields
4. Click "Process PDF" to download the processed file

Using the API

Process PDF (Multipart)

curl -X POST http://localhost:8080/api/pdf/process \
  -F "file=@sample.pdf" \
  -F "config='{\"placeholders\":{\"name\":\"John Doe\"}}'" \
  -o processed.pdf

Process PDF (JSON with Base64)

curl -X POST http://localhost:8080/api/process-json \
  -H "Content-Type: application/json" \
  -d '{
    "fileBase64": "<base64-encoded-pdf>",
    "configJson": {
      "placeholders": {
        "name": "John Doe",
        "date": "2024-01-15"
      },
      "formFields": {
        "firstName": "John",
        "lastName": "Doe"
      },
      "flattenAfterFill": true
    }
  }' \
  -o processed.pdf

Batch Processing

# Submit batch job
curl -X POST http://localhost:8080/pdf/bulk/async \
  -H "Content-Type: application/json" \
  -d '{
    "jobs": [
      {
        "fileBase64": "<base64-encoded-pdf-1>",
        "config": {"placeholders": {"name": "John"}}
      },
      {
        "fileBase64": "<base64-encoded-pdf-2>",
        "config": {"placeholders": {"name": "Jane"}}
      }
    ]
  }'

# Check job status
curl http://localhost:8080/pdf/status/{jobId}

# Download result
curl http://localhost:8080/pdf/download/{jobId} -o result.zip

API Documentation

Once the application is running, access the interactive API documentation at:

• Swagger UI: http://localhost:8080/swagger-ui.html
• OpenAPI JSON: http://localhost:8080/v3/api-docs

Configuration

Configuration can be modified in src/main/resources/application.properties:

# Server port
server.port=8080

# Upload limits (200MB default)
spring.servlet.multipart.max-file-size=200MB
spring.servlet.multipart.max-request-size=200MB

# Logging
logging.level.com.yaduinfotech.pdfeditor=DEBUG
logging.file.name=logs/pdfeditor.log

PDF Configuration Schema

Complete Configuration Example

{
  "placeholders": {
    "name": "John Doe",
    "email": "john@example.com",
    "date": "2024-01-15",
    "SIGNATURE": ""
  },
  "formFields": {
    "firstName": "John",
    "lastName": "Doe",
    "company": "Acme Corp"
  },
  "textFields": [
    {
      "name": "newField",
      "value": "Custom value",
      "page": 1,
      "x": 100,
      "y": 700,
      "width": 200,
      "height": 20
    }
  ],
  "signatureFields": [
    {
      "name": "signature",
      "page": 1,
      "x": 100,
      "y": 600,
      "width": 200,
      "height": 50
    }
  ],
  "flattenAfterFill": true
}

Configuration Options

Property	Type	Description
placeholders	Map<String, String>	Key-value pairs for replacing {{key}} text in the PDF
formFields	Map<String, String>	Key-value pairs for filling existing AcroForm fields
textFields	List	New text fields to add
signatureFields	List	New signature fields to add
flattenAfterFill	Boolean	Flatten PDF after filling (makes it non-editable)

TextFieldConfig

Property	Type	Default	Description
name	String	-	Field name (required)
value	String	""	Field value
page	Integer	1	Page number (1-based)
x	Float	0	X position from left
y	Float	0	Y position from bottom
width	Float	200	Field width
height	Float	20	Field height

SignatureFieldConfig

Property	Type	Default	Description
name	String	-	Field name (required)
page	Integer	1	Page number (1-based)
x	Float	0	X position from left
y	Float	0	Y position from bottom
width	Float	200	Field width
height	Float	50	Field height

Project Structure

pdfeditor/
├── src/main/
│   ├── java/com/yaduinfotech/pdfeditor/
│   │   ├── PdfEditorApplication.java    # Main application class
│   │   ├── PdfController.java           # REST controller for PDF processing
│   │   ├── AsyncPdfController.java      # REST controller for batch processing
│   │   ├── PdfService.java              # Core PDF processing logic
│   │   ├── config/                      # Configuration classes
│   │   ├── exception/                   # Exception handling
│   │   └── jobs/                        # Async job processing
│   └── resources/
│       ├── application.properties        # Application configuration
│       ├── static/                       # Web interface HTML files
│       │   ├── index.html               # Single PDF processor UI
│       │   ├── async-pdf.html           # Batch processor UI
│       │   └── job-status.html          # Job status UI
│       └── fonts/                        # Custom fonts (Arial)
├── pom.xml                              # Maven configuration
└── README.md                            # This file

License

This project is proprietary software developed by YaduInfotech.