How to encrypt zip file using zip4j

Question

I want to create password protected ZIP:

    // Set the compression level
    parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);

    // Se         


        

Answer 1

Zip4j supports the encryption of the file list...

Key features:

• Create, Add, Extract, Update, Remove files from a Zip file
• Read/Write password protected Zip files
• Supports AES 128/256 Encryption
• Supports Standard Zip Encryption
• Supports Zip64 format
• Supports Store (No Compression) and Deflate compression method
• Create or extract files from Split Zip files (Ex: z01, z02,...zip)
• Supports Unicode file names
• Progress Monitor

Take a look at this example code AddFilesWithAESEncryption.java:

// Initiate ZipFile object with the path/name of the zip file.
ZipFile zipFile = new ZipFile("c:\\ZipTest\\AddFilesWithAESZipEncryption.zip");

// Build the list of files to be added in the array list
// Objects of type File have to be added to the ArrayList
ArrayList filesToAdd = new ArrayList();
filesToAdd.add(new File("c:\\ZipTest\\sample.txt"));
filesToAdd.add(new File("c:\\ZipTest\\myvideo.avi"));
filesToAdd.add(new File("c:\\ZipTest\\mysong.mp3"));

// Initiate Zip Parameters
ZipParameters parameters = new ZipParameters();
// set compression method to deflate compression
parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE); 
parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_ULTRA); 

// Set the encryption flag to true
parameters.setEncryptFiles(true);

// Set the encryption method to AES Zip Encryption
parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_AES);

// Set AES Key strength. Key strengths available for AES encryption are:
parameters.setAesKeyStrength(Zip4jConstants.AES_STRENGTH_256);

// Set password
parameters.setPassword("test123!");

// Now add files to the zip file
zipFile.addFiles(filesToAdd, parameters);

Answer 2

Zip4j does not support the encryption of the file list because of patent issues.

See: http://www.lingala.net/zip4j/forum/index.php?topic=104.0

Update:

As stated in the link. The zip-specification does not include the encryption of the filelist. To hide the filenames you can create a zip-file including your files encapsulate it by zip it again. Hence if you open zip2.zip you will only see "zip1.zip" and not the original filenames.