Test.java

package net.sinender.ctcommand;

import java.io.*;
import java.net.URL;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

public class Test {
    public static void downloadFolderURL(String url, String zipDir, String folderDir, Consumer<Boolean> callback) {
        new Thread(() -> {
            try {
                URL website = new URL(url);
                ReadableByteChannel rbc = Channels.newChannel(website.openStream());
                FileOutputStream fos = new FileOutputStream(zipDir);
                fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
                fos.close();

                File file = new File(zipDir);
                File dest = new File(folderDir);
                dest.mkdir();
                //unzip the file
                unzip(zipDir, folderDir);
                //copy the files to the destination
                moveFolder(new File(folderDir + "/Hysentials-main"), new File(folderDir));
                //delete the zip file
                file.delete();
                //delete the folder
                deleteFolder(new File(folderDir + "/Hysentials-main"));
                callback.accept(true);
            } catch (Exception e) {
                e.printStackTrace();

            }
        }).start();
    }

    public static void unzip(String zipFilePath, String destDirectory) throws IOException {
        File destDir = new File(destDirectory);
        if (!destDir.exists()) {
            destDir.mkdir();
        }
        ZipInputStream zipIn = new ZipInputStream(new FileInputStream(zipFilePath));
        ZipEntry entry = zipIn.getNextEntry();
        // iterates over entries in the zip file
        while (entry != null) {
            String filePath = destDirectory + File.separator + entry.getName();
            if (!entry.isDirectory()) {
                // if the entry is a file, extracts it
                extractFile(zipIn, filePath);
            } else {
                // if the entry is a directory, make the directory
                File dir = new File(filePath);
                dir.mkdirs();
            }
            zipIn.closeEntry();
            entry = zipIn.getNextEntry();
        }
        zipIn.close();
    }

    /**
     * Extracts a zip entry (file entry)
     *
     * @param zipIn
     * @param filePath
     * @throws IOException
     */
    public static void extractFile(ZipInputStream zipIn, String filePath) throws IOException {
        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(filePath));
        byte[] bytesIn = new byte[4096];
        int read = 0;
        while ((read = zipIn.read(bytesIn)) != -1) {
            bos.write(bytesIn, 0, read);
        }
        bos.close();
    }

    //move the files from the temp folder to the destination
    public static void moveFolder(File source, File destination) throws IOException {
        if (source.isDirectory()) {
            if (!destination.exists()) {
                destination.mkdir();
            }
            String files[] = source.list();
            for (String file : files) {
                File srcFile = new File(source, file);
                File destFile = new File(destination, file);
                moveFolder(srcFile, destFile);
            }
        } else {
            Files.move(source.toPath(), destination.toPath(), StandardCopyOption.REPLACE_EXISTING);
        }
    }

    //delete the temp folder
    public static void deleteFolder(File folder) {
        File[] files = folder.listFiles();
        if (files != null) { //some JVMs return null for empty dirs
            for (File f : files) {
                if (f.isDirectory()) {
                    deleteFolder(f);
                } else {
                    f.delete();
                }
            }
        }
        folder.delete();
    }
}