* once Java 8 is no longer supported.
 */
public class PropertyResourceBundleFallbackCharset extends Charset {

    public PropertyResourceBundleFallbackCharset() {
        super(PropertyResourceBundleFallbackCharset.class.getCanonicalName(), new String[0]);
    }

    @Override
    public boolean contains(Charset charset) {
        return false;
    }

    private final byte[] utf8bytes =  [0xc3, 0xa2, 0x61, 0x62, 0x63, 0x64] as byte[]
    private final byte[] iso8859bytes = [0xe2, 0x61, 0x62, 0x63, 0x64] as byte[]

    def charset = new PropertyResourceBundleFallbackCharset()

    def "can decode a UTF-8 stream"() {
        when:
        CharBuffer result = charset.newDecoder().decode(buffer(utf8bytes))

        then:

        Hasher hasher = Hashing.newHasher();
        Properties properties = new Properties();
        properties.load(new InputStreamReader(inputStream, new PropertyResourceBundleFallbackCharset()));
        Map<String, String> entries = Maps.fromProperties(properties);
        entries
            .entrySet()
            .stream()
            .filter(entry ->