Descompactar Arquivo

public static byte[] compactar(byte[] fileIn, String fileName) {
        ByteArrayOutputStream fileOut = null;
        try {
            // Cria o ZIP e o Stream de saída
            fileOut = new ByteArrayOutputStream();
            ZipOutputStream zip = new ZipOutputStream(fileOut);
            //Adiciona o arquivo no zip
            zip.putNextEntry(new ZipEntry(fileName));
            zip.write(fileIn);
            zip.closeEntry();
            zip.close();

        } catch (Exception e) {
            e.printStackTrace();
        }
        
        //Retorna os bytes do ZIP
        return fileOut.toByteArray();
    }