Discover how to password‑protect an Excel file using a Java REST API in just a few simple steps. In this tutorial we’ll create a Java application that encrypts Excel spreadsheets with the Aspose.Cells Cloud API, following clear, step‑by‑step instructions. The resulting solution can be integrated into any Java‑based application on Linux, macOS, or Windows, and the conversion is completely free.

Prerequisite

• Create an account and get API credentials to password protect Excel using Java REST API
• Download Aspose.Cells Cloud SDK for Java to encrypt Excel file using Java Cloud API
• Setup Java project with the above SDK to protect an XLS file

Steps to Encrypt Excel File using Java Low Code API

1. Set the Client ID and Client Secret for the API to encrypt the Workbook with a password using Java REST API
2. Create an object of the CellsApi class with client credentials to perform password protection of an XLS file
3. Specify the source XLS file names and load the source XLS using a name and File object in a HashMap
4. Create an instance of the ProtectWorkbookRequest to set the password and other properties
5. Instantiate the PostProtectRequest object to set the map files and ProtectWorkbookRequest instance
6. Call the postProtect request method to encrypt Excel file using Java low code API
7. Save the encrypted Excel file/s on the local disk

The aforementioned steps password protect Excel using Java REST API. We will start the process with the configuration of the SDK and creating the CellsAPI class instance. We will then load the source XLS file/s using a HashMap and create an instance of the ProtectWorkbookRequest and PostProtectRequest classes that are further used for setting the password protection for the Excel files using the postProtect() method.

Code for Password Protect Excel using Java REST API

With just a few lines of code you can password‑protect Excel using the Java low‑code API. Provide the source Excel files, the password to apply, and any optional properties. After constructing the Request Message, invoking postProtect() encrypts the workbooks and returns the password‑protected Excel files, which you can store on disk or in a database.

In this tutorial we’ve covered how to encrypt a Workbook with a password using the Java REST API. If you’re interested in converting Excel files to PNG images, see our guide on Convert Excel to PNG with Java REST API.