GZip Compression/Decompression Java and C#

CompressionHelper.java

import android.util.Base64;

import com.google.android.gms.common.util.IOUtils;

import org.jetbrains.annotations.Nullable;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class CompressionHelper {

    @Nullable
    public static String compress(@Nullable String data) {
        if(data == null || data.length() == 0)
            return null;
        try {

            // Create an output stream, and a gzip stream to wrap over.
            ByteArrayOutputStream bos = new ByteArrayOutputStream(data.length());
            GZIPOutputStream gzip = new GZIPOutputStream(bos);

            // Compress the input string
            gzip.write(data.getBytes());
            gzip.close();
            byte[] compressed;
            // Convert to base64
            compressed = Base64.encode(bos.toByteArray(),Base64.NO_WRAP);
            bos.close();
            // return the newly created string
            return new String(compressed);
        } catch(IOException e) {

            return null;
        }
    }


    @Nullable
    public static String decompress(@Nullable String compressedText) {
        if(compressedText == null || compressedText.length() == 0)
            return null;
        try {
            // get the bytes for the compressed string
            byte[] compressed = compressedText.getBytes("UTF-8");

            // convert the bytes from base64 to normal string
            compressed = Base64.decode(compressed, Base64.NO_WRAP);

            ByteArrayInputStream bis = new ByteArrayInputStream(compressed);
            GZIPInputStream gis = new GZIPInputStream(bis);
            byte[] bytes = IOUtils.toByteArray(gis);
            return new String(bytes, "UTF-8");

        }catch (IOException e){
            e.printStackTrace();
        }

        return null;
    }

}

CompressionTools.cs

using ICSharpCode.SharpZipLib.GZip; //PM> Install-Package SharpZipLib
using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace GeneralTools
{
    public static class CompressionTools
    {
        public static string CompressString(string text)
        {
            if (string.IsNullOrEmpty(text))
                return null;
            byte[] buffer = Encoding.UTF8.GetBytes(text);
            using (var compressedStream = new MemoryStream())
            {
                GZip.Compress(new MemoryStream(buffer), compressedStream, false);
                byte[] compressedData = compressedStream.ToArray();
                return Convert.ToBase64String(compressedData);
            }
        }


        public static string DecompressString(string compressedText)
        {
            if (string.IsNullOrEmpty(compressedText))
                return null;
            byte[] gZipBuffer = Convert.FromBase64String(compressedText);
            using (var memoryStream = new MemoryStream())
            {
                using (var compressedStream = new MemoryStream(gZipBuffer))
                {
                    var decompressedStream = new MemoryStream();
                    GZip.Decompress(compressedStream, decompressedStream, false);

                    return Encoding.UTF8.GetString(decompressedStream.ToArray()).Trim();
                }
            }
        }


    }

}

This is a working pair of code to compress/decompress strings using GZIP between Java and C#.
remember do not use GZipStream class , since it is buggy.