ObfuscatedResourcePackExtractor.kt

import java.io.BufferedInputStream
import java.io.BufferedOutputStream
import java.io.File
import java.io.FileOutputStream
import java.util.*
import java.util.zip.ZipEntry
import java.util.zip.ZipFile

private fun extractFolder(zipFile: String, extractFolder: String) {
    try {
        val BUFFER = 2048
        val file = File(zipFile)

        val zip = ZipFile(file)
        val newPath = extractFolder

        File(newPath).mkdir()
        val zipFileEntries: Enumeration<*> = zip.entries()

        // Process each entry
        while (zipFileEntries.hasMoreElements()) {
            // grab a zip file entry
            val entry = zipFileEntries.nextElement() as ZipEntry
            val currentEntry = entry.name

            val destFile = File(newPath, currentEntry)
            //destFile = new File(newPath, destFile.getName());
            val destinationParent = destFile.parentFile

            // create the parent directory structure if needed
            destinationParent.mkdirs()

            if (!entry.isDirectory) {
                val `is` = BufferedInputStream(
                    zip
                        .getInputStream(entry)
                )
                var currentByte: Int
                // establish buffer for writing file
                val data = ByteArray(BUFFER)

                // write the current file to disk
                val fos = FileOutputStream(destFile)
                val dest = BufferedOutputStream(
                    fos,
                    BUFFER
                )

                // read and write until last byte is encountered
                while ((`is`.read(data, 0, BUFFER).also { currentByte = it }) != -1) {
                    dest.write(data, 0, currentByte)
                }
                dest.flush()
                dest.close()
                `is`.close()
            }
        }
    } catch (e: Exception) {
        println("ERROR: " + e.message)
    }
}

fun main() {
    val zipFilePath = "input_here.zip"
    val destDirectory = "output_folder_here"
    extractFolder(zipFilePath, destDirectory)
    println("Unzipping completed!")
}