Converting Zip file to bytearray and vice versa

[Alpesh Rathod]

Hi I want to convert a zip file to byte array and then use that byte array to create a new zip file??

Please anyone how do i do it??

[Niv Tyagi]

Have you tried : java.util.zip.ZipInputStream

[Rob Spoor]

The ZIP file does not need to be unzipped, so ZipInputStream is not necessary.

Use a FileInputStream to read the ZIP file and a ByteArrayOutputStream to write its contents to. Get the latter's byte[]. Use ByteArrayInputStream and FileOutputStream to reverse the process.

[mahavir swami]

ZipFile zip = new ZipFile("abc.zip");
//now say the entry in zip file has name "abc.txt"

ZipEntry entry = new ZipEntry("abc.txt");

BufferedInputStream istream = new BufferedInputStream(zip.getInputStream(entry));
int file_size  = (int) entry.getCompressedSize();
byte[] blob = new byte[(int) entry.getCompressedSize()];
		int bytes_read = 0;
		int offset = 0;
		
		while((bytes_read = istream.read(blob, 0, file_size)) != -1)
		{
			offset += bytes_read;
		}


//closing every thing
		zip.close();
		istream.close();
return blob

so this will convert your zip entry into byte array

now you want this byte array gain to be written in zip so

ZipOutputStream zos = new ZipOutputStream(new BufferedOutputStream(new FileOutputStream("zipfilename")));
//now create the entry in zip file

ZipEntry entry = new ZipEntry("entry name");
zos.putNextEntry(entry);
zos.write(byte_array);
zos.close();