Compress multiple files into a zip file and assign a password.

First things first, include maven dependency to download zip4j jar files

1 <dependency>
2     <groupId>net.lingala.zip4j</groupId>
3     <artifactId>zip4j</artifactId>
4     <version>1.3.1</version>
5 </dependency>

Second, write the zip method, either can be a static util method or a private method within a class.

/**
     *
     * @param path, the absolute path where the zip file is
     * @param fileList, a list of File objects that is going to be zipped
     * @param password, need to be entered for extraction
     * Create a zip file with password protected
     * @throws ZipException
     */
    public static void createZipWithPassword(String path, ArrayList<File> fileList, String password) throws ZipException {
            final ZipFile zipFile = new ZipFile(path);
            final ZipParameters parameters = new ZipParameters();
            parameters.setEncryptFiles(true);
            parameters.setCompressionMethod(Zip4jConstants.COMP_DEFLATE);
            parameters.setCompressionLevel(Zip4jConstants.DEFLATE_LEVEL_NORMAL);
            parameters.setEncryptionMethod(Zip4jConstants.ENC_METHOD_STANDARD);
            parameters.setPassword(password);
            zipFile.createZipFile(fileList, parameters);
    }