<dependency>
    <groupId>com.groupdocs</groupId>
    <artifactId>groupdocs-merger-cloud</artifactId>
    <version>25.11</version>
</dependency>

String clientId = "YOUR_CLIENT_ID";
String clientSecret = "YOUR_CLIENT_SECRET";

Configuration config = new Configuration(clientId, clientSecret);
MergerApi mergerApi = new MergerApi(config);

FileInfo inputFile = new FileInfo();
inputFile.setFilePath("input.xlsx");   // source Excel file

String outputPath = "output_protected.xlsx"; // destination file

ProtectOptions protectOptions = new ProtectOptions();
protectOptions.setFileInfo(inputFile);
protectOptions.setOutputPath(outputPath);
protectOptions.setPassword("MySecretPassword"); // desired password

ProtectDocumentRequest request = new ProtectDocumentRequest(protectOptions);

try {
    mergerApi.protectDocument(request);
    System.out.println("Excel file has been password protected successfully.");
    System.out.println("Protected file stored at: " + outputPath);
} catch (ApiException e) {
    System.err.println("Error while protecting the Excel file:");
    System.err.println("Status Code: " + e.getCode());
    System.err.println("Message: " + e.getMessage());
}

import com.groupdocs.merger.cloud.ApiException;
import com.groupdocs.merger.cloud.Configuration;
import com.groupdocs.merger.cloud.api.MergerApi;
import com.groupdocs.merger.cloud.model.FileInfo;
import com.groupdocs.merger.cloud.model.ProtectOptions;
import com.groupdocs.merger.cloud.model.requests.ProtectDocumentRequest;

public class ProtectExcelExample {
    public static void main(String[] args) {
        // Replace with your actual client credentials
        String clientId = "YOUR_CLIENT_ID";
        String clientSecret = "YOUR_CLIENT_SECRET";

// Initialize the API configuration
        Configuration config = new Configuration(clientId, clientSecret);
        MergerApi mergerApi = new MergerApi(config);

// Define input and output file locations (relative to the storage root)
        FileInfo inputFile = new FileInfo();
        inputFile.setFilePath("input.xlsx");          // source Excel file
        String outputPath = "output_protected.xlsx";  // destination file

// Set password protection options
        ProtectOptions protectOptions = new ProtectOptions();
        protectOptions.setFileInfo(inputFile);
        protectOptions.setOutputPath(outputPath);
        protectOptions.setPassword("MySecretPassword"); // desired password

// Build the request
        ProtectDocumentRequest request = new ProtectDocumentRequest(protectOptions);

try {
            // Execute the password protection operation
            mergerApi.protectDocument(request);
            System.out.println("Excel file has been password protected successfully.");
            System.out.println("Protected file stored at: " + outputPath);
        } catch (ApiException e) {
            System.err.println("Error while protecting the Excel file:");
            System.err.println("Status Code: " + e.getCode());
            System.err.println("Message: " + e.getMessage());
        }
    }
}

curl -X POST "https://api.groupdocs.cloud/v2.0/auth/token" \
     -H "Content-Type: application/json" \
     -d '{
           "client_id": "YOUR_CLIENT_ID",
           "client_secret": "YOUR_CLIENT_SECRET"
         }'

curl -X PUT "https://api.groupdocs.cloud/v2.0/storage/file/input.xlsx" \
     -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
     -H "Content-Type: application/octet-stream" \
     --data-binary @input.xlsx

curl -X POST "https://api.groupdocs.cloud/v2.0/merger/protect" \
     -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
     -H "Content-Type: application/json" \
     -d '{
           "fileInfo": { "filePath": "input.xlsx" },
           "outputPath": "output_protected.xlsx",
           "password": "MySecretPassword"
         }'

curl -X GET "https://api.groupdocs.cloud/v2.0/storage/file/output_protected.xlsx" \
     -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
     -o output_protected.xlsx