System.util.zlib.ZDeflaterOutputStream.Finish C# (CSharp) Method

        public void Finish()
        {
            int err;
            do{
                z.next_out=buf;
                z.next_out_index=0;
                z.avail_out=BUFSIZE;
                err=z.deflate(JZlib.Z_FINISH);
                if(err!=JZlib.Z_STREAM_END && err != JZlib.Z_OK)
                    throw new IOException("deflating: "+z.msg);
                if(BUFSIZE-z.avail_out>0){
                    outp.Write(buf, 0, BUFSIZE-z.avail_out);
                }
            }
            while(z.avail_in>0 || z.avail_out==0);
            Flush();
        }

 /**
 * Compresses the stream.
 * @param compressionLevel the compression level (0 = best speed, 9 = best compression, -1 is default)
 * @since   2.1.3
 */
 virtual public void FlateCompress(int compressionLevel) {
     if (!Document.Compress)
         return;
     // check if the flateCompress-method has already been used
     if (compressed) {
         return;
     }
     this.compressionLevel = compressionLevel;
     if (inputStream != null) {
         compressed = true;
         return;
     }
     // check if a filter already exists
     PdfObject filter = PdfReader.GetPdfObject(Get(PdfName.FILTER));
     if (filter != null) {
         if (filter.IsName()) {
             if (PdfName.FLATEDECODE.Equals(filter))
                 return;
         }
         else if (filter.IsArray()) {
             if (((PdfArray) filter).Contains(PdfName.FLATEDECODE))
                 return;
         }
         else {
             throw new PdfException(MessageLocalization.GetComposedMessage("stream.could.not.be.compressed.filter.is.not.a.name.or.array"));
         }
     }
     // compress
     MemoryStream stream = new MemoryStream();
     ZDeflaterOutputStream zip = new ZDeflaterOutputStream(stream, compressionLevel);
     if (streamBytes != null)
         streamBytes.WriteTo(zip);
     else
         zip.Write(bytes, 0, bytes.Length);
     //zip.Close();
     zip.Finish();
     // update the object
     streamBytes = stream;
     bytes = null;
     Put(PdfName.LENGTH, new PdfNumber(streamBytes.Length));
     if (filter == null) {
         Put(PdfName.FILTER, PdfName.FLATEDECODE);
     }
     else {
         PdfArray filters = new PdfArray(filter);
         filters.Add(0, PdfName.FLATEDECODE);
         Put(PdfName.FILTER, filters);
     }
     compressed = true;
 }