public String decompress(String compressorName, String compressedString) throws IOException {
    Checks.notNull(compressedString, "compressedString cannot be null");
    Compressor compressor = getCompressor(compressorName);
    return new String(compressor.decompress(base64Decode(compressedString)), DEFAULT_ENCODING);
  }
@Test
  public void decompressShouldThrowExceptionIfCompressorNotFound() {
    AssertHelper.assertThrows(
        "decompress should throw exception if compressor not found",
        NullPointerException.class,
        "unknown compressorName: abcd",
        () -> stringCodec.decompress("abcd", "H4sIAAAAAAAA/0tMBAMAdCCLWwcAAAA="));
  }