testTask

package th.in.oneauthen;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Base64;

public class testDecodePdf {
    public static void main(String[] args) throws IOException {
        String filePath = "C:\\user\\Desktop\\dir1\\dir2\\";
        String filePathDes = "C:\\user\\Desktop\\dir1\\";

        File folder = new File(filePath);
        File[] listOfFiles = folder.listFiles();
        if (folder.isDirectory()) {
            if (folder.list().length > 0) {
                for (File file : listOfFiles) {
                    if (file.isFile()) {
                        byte[] input_file = Files.readAllBytes(Paths.get(filePath + file.getName()));

                        byte[] encodedBytes = Base64.getEncoder().encode(input_file);
                        String encodedString = new String(encodedBytes);
                        byte[] decodedBytes = Base64.getDecoder().decode(encodedString.getBytes());

                        FileOutputStream fos = new FileOutputStream(filePathDes + file.getName());
                        fos.write(decodedBytes);
                        fos.flush();
                        fos.close();
                        System.out.println(file.getName());
                        String Del = filePath + file.getName();
                        Files.delete(Paths.get(Del));

                    }

                }
            } else {

                System.out.println("Directory is empty!");

            }
        } else {

            System.out.println("This is not a directory");
        }
    }

}