How to encrypt, password-protect and set restricted permissions on a PDF in Java

Today we will be looking at the document workhorse that is PDF, and how to programmatically employ various features: encryption, password protection, and setting permissions. For Java users, this would normally be a very time-consuming process. However, this article will be covering a much simpler approach to these tasks, as you will soon see.

We start by adding two references. First for Jitpack among our repositories:

<repositories>
    <repository>
        <id>jitpack.io</id>
        <url>https://jitpack.io</url>
    </repository>
</repositories>

Then add our client to dependencies.

<dependencies>
<dependency>
    <groupId>com.github.Cloudmersive</groupId>
    <artifactId>Cloudmersive.APIClient.Java</artifactId>
    <version>v3.54</version>
</dependency>
</dependencies>

And now we can call our function for PDF encryption. Use the parameters to customize your desired permissions, passwords, etc.

// Import classes:
//import com.cloudmersive.client.invoker.ApiClient;
//import com.cloudmersive.client.invoker.ApiException;
//import com.cloudmersive.client.invoker.Configuration;
//import com.cloudmersive.client.invoker.auth.*;
//import com.cloudmersive.client.EditPdfApi;
ApiClient defaultClient = Configuration.getDefaultApiClient();
// Configure API key authorization: Apikey
ApiKeyAuth Apikey = (ApiKeyAuth) defaultClient.getAuthentication("Apikey");
Apikey.setApiKey("YOUR API KEY");
// Uncomment the following line to set a prefix for the API key, e.g. "Token" (defaults to null)
//Apikey.setApiKeyPrefix("Token");
EditPdfApi apiInstance = new EditPdfApi();
String ownerPassword = "ownerPassword_example"; // String | Password of a owner (creator/editor) of the PDF file (required)
String userPassword = "userPassword_example"; // String | Password of a user (reader) of the PDF file (optional)
File inputFile = new File("/path/to/file.txt"); // File | Input file to perform the operation on.
String encryptionKeyLength = "encryptionKeyLength_example"; // String | Possible values are \"128\" (128-bit RC4 encryption) and \"256\" (256-bit AES encryption).  Default is 256.
Boolean allowPrinting = true; // Boolean | Set to false to disable printing through DRM.  Default is true.
Boolean allowDocumentAssembly = true; // Boolean | Set to false to disable document assembly through DRM.  Default is true.
Boolean allowContentExtraction = true; // Boolean | Set to false to disable copying/extracting content out of the PDF through DRM.  Default is true.
Boolean allowFormFilling = true; // Boolean | Set to false to disable filling out form fields in the PDF through DRM.  Default is true.
Boolean allowEditing = true; // Boolean | Set to false to disable editing in the PDF through DRM (making the PDF read-only).  Default is true.
Boolean allowAnnotations = true; // Boolean | Set to false to disable annotations and editing of annotations in the PDF through DRM.  Default is true.
Boolean allowDegradedPrinting = true; // Boolean | Set to false to disable degraded printing of the PDF through DRM.  Default is true.
try {
byte[] result = apiInstance.editPdfSetPermissions(ownerPassword, userPassword, inputFile, encryptionKeyLength, allowPrinting, allowDocumentAssembly, allowContentExtraction, allowFormFilling, allowEditing, allowAnnotations, allowDegradedPrinting);
System.out.println(result);
} catch (ApiException e) {
System.err.println("Exception when calling EditPdfApi#editPdfSetPermissions");
e.printStackTrace();
}

And you are already done! Simple.