How to zip the contents inside a directory

I want to make a zip file of all contents inside a directory including subfolders & files,
I have a directory called Documents, in my code Document directory gets included in zip file, but I want only the contents within the Document directory
i.e folder1,folder2,folder3, file.txt
it should exclude Document directory in zip file, but all the contents(folders & files) within it, should be present
Please Help.

The directory structure is:

Document/
>folder1 ( Document/folder1 )
>file1.txt ( Document/folder1/file1.txt )
folder2 ( Document/folder2 )
>file2.txt ( Document/folder2/file2.txt )
folder3 ( Document/folder3 )
>file3.txt ( Document/folder3/file3.txt )
file.txt ( Document/file.txt )

Code:

import java.util.ArrayList;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
 
public class TestZipUtil {
    public static void main(String[] args) throws Exception {
        
        ZipUtil zipper = new ZipUtil();
        File directoryToZip = new File("C:/Document");
        String zipFilePath = "C:/word.zip";
        List<File> listFiles = new ArrayList<File>(1);
        listFiles.add(directoryToZip);
        
        zipper.compressFiles(listFiles, zipFilePath);
    }
}

class ZipUtil {
    
    private static final int BUFFER_SIZE = 4096;
    
   public void compressFiles(List<File> listFiles, String destZipFile) throws FileNotFoundException, IOException {
        
       ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(destZipFile));
        
       for (File file : listFiles) {
           if (file.isDirectory()) {
               addFolderToZip(file, file.getName(), zos);
           } else {
               addFileToZip(file, zos);
           }
       }
        
       zos.flush();
       zos.close();
   }
    
    private void addFolderToZip(File folder, String parentFolder,
            ZipOutputStream zos) throws FileNotFoundException, IOException {
        for (File file : folder.listFiles()) {
            if (file.isDirectory()) {
                addFolderToZip(file, parentFolder + "/" + file.getName(), zos);
                continue;
            }
 
            zos.putNextEntry(new ZipEntry(parentFolder + "/" + file.getName()));
 
            BufferedInputStream bis = new BufferedInputStream(
                    new FileInputStream(file));
 
            long bytesRead = 0;
            byte[] bytesIn = new byte[BUFFER_SIZE];
            int read = 0;
 
            while ((read = bis.read(bytesIn)) != -1) {
                zos.write(bytesIn, 0, read);
                bytesRead += read;
            }
 
            zos.closeEntry();
 
        }
    }
 
    private void addFileToZip(File file, ZipOutputStream zos)
            throws FileNotFoundException, IOException {
        zos.putNextEntry(new ZipEntry(file.getName()));
 
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(
                file));
 
        long bytesRead = 0;
        byte[] bytesIn = new byte[BUFFER_SIZE];
        int read = 0;
 
        while ((read = bis.read(bytesIn)) != -1) {
            zos.write(bytesIn, 0, read);
            bytesRead += read;
        }
 
        zos.closeEntry();
    }
}

The Document directory is being included because you are adding it to listFiles on line 19. Instead you should be adding all the files and directories in Documents at this point.

And welcome to the Ranch

How to add only the contents within directory in line 16 if possible
or is the way to remove "Document/" or "Document"in addFolderToZip method

I would get rid of your compressFiles method and replace lines 17 - 21 with