Easily Convert Markdown to Word, PDF, and HTML in Java

In software development and technical writing, Markdown has become a widely used lightweight markup language. Its simple syntax and high writing efficiency make it perfect for quickly jotting down notes, drafting technical documentation, or creating blog posts. However, in practical applications, Markdown files often need to be converted into more commonly used formats, such as:

• Word
• PDF
• HTML

This article will explain how to convert Markdown into Word, PDF, and HTML in a Java environment, with code examples demonstrating each step of the process.

Why Convert Markdown to Word, PDF, and HTML?

Markdown to Word
Word is highly functional for document editing and formatting, making it ideal for documents that require frequent revisions and complex layouts, such as technical manuals or project documentation.

Markdown to PDF

PDF is a universal document format that ensures consistent display across different devices and platforms. It is especially well-suited for sharing and long-term storage.

Markdown to HTML

HTML is the core language of web pages. After conversion, the content can be directly embedded into websites, wikis, or blogs, making it convenient for web-based display.

Common Approaches for Converting Markdown to Word, PDF, and HTML in Java

Several approaches can be used in Java for converting Markdown to Word, PDF, and HTML:

• Using Markdown Parsing Libraries
  Libraries like commonmark-java or flexmark-java can convert Markdown to HTML. However, additional tools are needed for converting to Word or PDF, which adds complexity to the process.

• Using Online Services
  You can upload a Markdown file to a server and receive the converted file in the desired format. This method is simple but comes with network dependencies and potential data security concerns, making it unsuitable for privacy-sensitive scenarios.

• Using Document Processing Libraries
  Some libraries, such as Spire.Doc for Java, allow for loading and saving multiple document formats, enabling direct conversion of Markdown into Word, PDF, and HTML. Spire.Doc for Java provides a Java-based solution that does not require Microsoft Office or third-party services.

Introduction to Spire.Doc for Java

Spire.Doc for Java is a document processing library designed specifically for Java applications. It offers a rich API that supports:

• Creating, reading, and editing Word documents.
• Converting Word documents into PDF, HTML, and image formats.
• Importing and converting Markdown, RTF, TXT, and other files into Word, PDF, HTML, and image formats.
• Customizing complex document elements like paragraphs, tables, and styles.

By using Spire.Doc for Java, you can convert Markdown directly into Word, PDF, and HTML, saving significant development time compared to manually parsing Markdown syntax and outputting to these formats.

Installation Methods

Spire.Doc for Java offers two installation options:

Method 1: Maven Integration

Add the following dependency to your pom.xml:

<repositories>
    <repository>
        <id>com.e-iceblue</id>
        <name>e-iceblue</name>
        <url>https://repo.e-iceblue.com/nexus/content/groups/public/</url>
    </repository>
</repositories>
<dependencies>
    <dependency>
        <groupId>e-iceblue</groupId>
        <artifactId>spire.doc</artifactId>
        <version>13.10.6</version>
    </dependency>
</dependencies>

(You can check the latest version in the official Maven repository.)

Method 2: Manual JAR File Integration

Download the JAR file from the official website and import it into your project.

Implementation Steps

The process of converting Markdown to Word, PDF, and HTML using Spire.Doc for Java is straightforward and can be broken down into the following steps:

• Create a Document Object This object serves as a container for the document.
• Load the Markdown File Use the loadFromFile() method to load the .md file into the Document object.
• Save to the Desired Format Use the saveToFile() method to save the document in the desired format (Word, PDF, or HTML).

Now, let’s take a look at the code examples for converting Markdown to each of these formats.

Java Markdown to Word

Converting Markdown to Word is the most common requirement when documents need further editing and formatting.

Example Code:

import com.spire.doc.*;

public class MarkdownToWord {
    public static void main(String[] args) {
        // Create Document object
        Document document = new Document();

        // Load the Markdown file
        document.loadFromFile("input.md", FileFormat.Markdown);

        // Save as Word format (.docx)
        document.saveToFile("output.docx", FileFormat.Docx);

        // Close the document
        document.close();
    }
}

After execution, elements such as headings, paragraphs, lists, tables, and images in the Markdown file will be preserved and converted into an editable Word document.

Java Markdown to PDF

When the markdown document needs to be archived, distributed, or printed, PDF is the ideal format.

Example Code:

import com.spire.doc.*;

public class MarkdownToPdf {
    public static void main(String[] args) {
        Document document = new Document();

        // Load the Markdown file
        document.loadFromFile("input.md", FileFormat.Markdown);

        // Save as PDF format
        document.saveToFile("output.pdf", FileFormat.PDF);

        document.close();
    }
}

The resulting PDF document retains the structure and style of the original Markdown, with cross-platform consistency.

Java Markdown to HTML

When displaying markdown content on web pages or knowledge bases, converting Markdown to HTML is a convenient option.

Example Code:

import com.spire.doc.*;

public class MarkdownToHtml {
    public static void main(String[] args) {
        Document document = new Document();

        // Load the Markdown file
        document.loadFromFile("input.md", FileFormat.Markdown);

        // Save as HTML format
        document.saveToFile("output.html", FileFormat.Html);

        document.close();
    }
}

The generated HTML file can be directly embedded into websites or systems, eliminating the need for manual HTML coding.

Additional Features

Spire.Doc for Java not only allows you to convert Markdown to Word, PDF, and HTML, but also offers additional features such as:

• Batch Conversion : Process multiple Markdown files in a loop and convert them into different formats all at once.
• Customize Page Setup for Result Documents : Customize page settings such as page size, orientation, and margins using the PageSetup property of each document section.
• Convert to Images : Output Markdown files as PNG or JPG images, which can be used in reports or presentations.

Conclusion

Although Markdown is simple, it often needs to be converted into formats like Word, PDF, or HTML for better functionality in different contexts.

In a Java environment, using a document processing library like Spire.Doc for Java allows for quick and easy conversions, with additional features for enhanced customization. For developers who frequently handle Markdown files, this solution offers efficiency and stability.