CSV (Comma-Separated Values) files are widely used for storing structured data. As applications scale and produce modular datasets—such as logs, analytics, or financial records—developers often need to combine multiple CSV files into one consolidated document for easier processing and analysis. In this article, you will learn how to merge CSV files in Java programmatically and automate document merging workflows using the cloud-powered Java REST API. Developers can avoid the overhead of managing file streams or writing complex logic with this approach.

Steps to Merge CSV Files Using Java

1. Sign up and get your API credentials from the GroupDocs Cloud Dashboard
2. Download the GroupDocs.Merger Cloud Java SDK and create a Java project
3. Set up your API credentials with the Configuration class
4. For merging CSV files, create an instance of the DocumentApi class
5. Configure the source CSV files to join using FileInfo and JoinItem
6. Define the merging options, including the output file with JoinOptions
7. Process the request to join two CSV files with the join() method

By following this process, you can join CSV documents in Java apps using only a few API requests and minimal coding. When building cloud-based applications, choosing the right tool for data manipulation is paramount. Merging CSV files in Java via REST API boosts productivity by offloading the processing to the Cloud API’s secure infrastructure and avoiding resource bottlenecks. Developers can use the output CSV across platforms seamlessly, making this solution a strong alternative to bulkier desktop-based tools.

Code to Merge CSV Files Using Java

If you are working with separate datasets and need a cloud-native way to combine two or more CSV files in Java, the GroupDocs.Merger Cloud Java SDK delivers the flexibility and ease you need. With a few simple steps, consolidating multiple files and simplifying data handling in your web or desktop Java apps becomes effortless. Developers building cloud-integrated Java applications can use this approach to merge CSV files without relying on local file handling or bulky external libraries.

Refer to our guide on Merging TXT Files Using the Java REST API to learn about the process of combining plain text files in your Java backends.