Merge HTML Files in Java

How Merge HTML Works in Aspose.HTML for Java

Merge HTML in Aspose.HTML for Java is implemented as the sequential rendering of multiple HTML documents into a single output file. Each HTML document is processed independently and rendered in order into the same output device (PDF, DOCX, XPS, or image formats).

Online HTML Merger

Online HTML Merger lets you merge multiple HTML files into a single document in real time right in your browser. Please load HTML files from the local file system or a URL, select the required output format, and run the example! It’s fast, easy, secure, and completely free! You will immediately get the result as a separate file. So, quickly merge HTML files and save the result to PDF, XPS, DOCX, TIFF, or MHTML format online!

Steps to Merge HTML Files in Java

Please see the example above if you would like to merge HTML programmatically. Aspose.HTML for Java processes multiple HTML documents using a rendering pipeline:

1. Load HTML files using HTMLDocument. Each HTML file is loaded as a separate document and parsed into its own DOM. All resources such as styles, images, and fonts are resolved independently, so every document remains fully isolated at this stage.
2. Create HtmlRenderer. The renderer initializes the processing engine responsible for converting DOM trees into a visual output. It controls rendering but does not merge or modify the document structure.
3. Select output device (PDF, DOCX, XPS, Image). The output device defines the target format and controls how the rendered content is serialized.
4. Pass multiple documents to render(). All documents are processed sequentially. Each DOM is rendered independently, and the resulting output is written to a single continuous stream managed by the selected device.
5. Generate a single combined output file. The final result is one output file where all documents appear in sequence according to their input order.

How Rendering Multiple HTML Documents Works

Aspose.HTML for Java API provides the Renderer class for rendering and merging HTML documents. Using Renderer instances directly, you can send multiple files to the output rendering device at once. Aspose.HTML for Java uses a rendering pipeline model where each document is processed independently and written to a shared output device.

• Supported renderers: HtmlRenderer , SvgRenderer , MhtmlRenderer , and EpubRenderer , which are used to render HTML, SVG, MHTML, and EPUB documents, respectively.
• Supported output devices: PdfDevice, XpsDevice, DocDevice, and ImageDevice. Each device defines the final output format.

Get Started with Aspose.HTML for Java Library

Aspose.HTML for Java is an advanced web scraping and HTML parsing library. One can create, edit, navigate through nodes, extract data and convert HTML, XHTML, and MHTML files to PDF, Images, and other formats. Moreover, it also handles CSS, HTML Canvas, SVG, XPath, and JavaScript out-of-the-box to extend manipulation tasks. It’s a standalone API and does not require any software installation.
You can download its latest version directly from Aspose Maven Repository and install it within your Maven-based project by adding the following configurations to the pom.xml.

<repository>
<id>AsposeJavaAPI</id>
<name>Aspose Java API</name>
<url>https://repository.aspose.com/repo/</url>
</repository>

<dependency>
<groupId>com.aspose</groupId>
<artifactId>aspose-html</artifactId>
<version>version of aspose-html API</version>
<classifier>jdk17</classifier>
</dependency>