How to create Password protected GZIP java

Question

I want to create password protected Gzip file in java. Is there any commons jar for that.

I tried with GzipParameters, but there is no options for password.

Thanks in advance.

Answer 1

Refer to the following library https://github.com/srikanth-lingala/zip4j

Maven Dependency

    <dependency>
        <groupId>net.lingala.zip4j</groupId>
        <artifactId>zip4j</artifactId>
        <version>2.9.0</version>
    </dependency>

Sample Code

import net.lingala.zip4j.ZipFile;
import net.lingala.zip4j.exception.ZipException;
import net.lingala.zip4j.model.ZipParameters;
import net.lingala.zip4j.model.enums.CompressionLevel;
import net.lingala.zip4j.model.enums.EncryptionMethod;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class ZipAndUnZipFiles {


    public static void main(String[] args) {

        List<File> files = new ArrayList<File>();

        files.add(new File("C:\\code\\demo\\aFile.txt"));
        files.add(new File("C:\\code\\demo\\bFile.txt"));

        try {
            zip(files, "C:\\code\\demo\\compressed.zip", "password123");
        } catch (ZipException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            unZip(new File("C:\\code\\demo\\compressed.zip"), "password123", "C:\\code\\demo\\extracted\\");
        } catch (ZipException e) {
            e.printStackTrace();
        }

    }

    private static void zip( List<File> filesToAdd , String outputZipFilePath, String password) throws IOException {

        ZipParameters zipParameters = new ZipParameters();
        zipParameters.setEncryptFiles(true);
        zipParameters.setCompressionLevel(CompressionLevel.HIGHER);
        zipParameters.setEncryptionMethod(EncryptionMethod.AES);

        ZipFile zipFile = new ZipFile(outputZipFilePath, password.toCharArray());
        zipFile.addFiles(filesToAdd, zipParameters);

        zipFile.close();

    }

    private static void unZip(File zipFileInput, String password, String destinationDirectory) throws ZipException {

        ZipFile zipFile = new ZipFile(zipFileInput, password.toCharArray());
        zipFile.extractAll(destinationDirectory);
    }
}

Answer 2

The gzip format does not have any sort of encryption as an option for that format. You would simply encrypt the .gz file with, for example, gpg.