equivalent-exchange-3/src/main/java/com/pahimar/ee3/util/CompressionHelper.java

package com.pahimar.ee3.util;

import java.io.*;
import java.nio.charset.StandardCharsets;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class CompressionHelper {
    /**
     *
     * @param uncompressedString
     * @return
     */
    public static byte[] compress(String uncompressedString) {
        ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();

        try (
            GZIPOutputStream gzipOutputStream
            = new GZIPOutputStream(byteArrayOutputStream)
        ) {
            gzipOutputStream.write(uncompressedString.getBytes(StandardCharsets.UTF_8));
            gzipOutputStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return byteArrayOutputStream.toByteArray();
    }

    /**
     *
     * @param compressedString
     * @return
     */
    public static String decompress(byte[] compressedString) {
        StringBuilder stringBuilder = new StringBuilder();
        String line;
        try (
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(
                new GZIPInputStream(new ByteArrayInputStream(compressedString)),
                StandardCharsets.UTF_8
            ))
        ) {
            while ((line = bufferedReader.readLine()) != null) {
                stringBuilder.append(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        return stringBuilder.toString();
    }
}