@Override
    public String getGroupId() {
        return emptify(metadata.getGroupId());
    }

    @Override
    public String getArtifactId() {
        return metadata.storedInGroupDirectory() ? "" : emptify(metadata.getArtifactId());
    }

    @Override
    public String getVersion() {
        return metadata.storedInArtifactVersionDirectory() ? emptify(metadata.getBaseVersion()) : "";
    }

    @Override

    source.close()
    assertThat(relay.isClosed).isTrue()
    assertFile(Relay.PREFIX_CLEAN, 13L, metadata.size, "abcdefghijklm", metadata)
  }

  @Test
  fun multipleSources() {
    val upstream = Buffer()
    upstream.writeUtf8("abcdefghijklm")
    val relay = edit(file, upstream, metadata, 1024)
    val source1 = relay.newSource()!!.buffer()
    val source2 = relay.newSource()!!.buffer()

    /**
     * Merge a new metadata set into this piece of metadata.
     * TODO this should only be needed on the repository metadata {@link org.apache.maven.artifact.metadata.ArtifactMetadata}
     *
     * @param metadata the new metadata
     */
    void merge(ArtifactMetadata metadata);

    /**
     * Store the metadata in the local repository.

     * @throws RepositoryMetadataDeploymentException in case of metadata deployment issue
     */
    void deploy(ArtifactMetadata metadata, ArtifactRepository localRepository, ArtifactRepository deploymentRepository)
            throws RepositoryMetadataDeploymentException;

    /**
     * Install the metadata in the local repository.
     *
     * @param metadata        the metadata
     * @param localRepository the local repository

		if err == io.EOF {
			err = io.ErrUnexpectedEOF
		}
		r.err = err
		return m, err
	}
	m.metadata, err = r.mr.ReadBytes(metaDataPoolGet())
	if err == io.EOF {
		err = io.ErrUnexpectedEOF
	}
	if len(m.metadata) == 0 && cap(m.metadata) >= metaDataReadDefault {
		metaDataPoolPut(m.metadata)
		m.metadata = nil
	}
	r.err = err
	return m, err
}

// next will read one entry from the stream.

					return
				}
			}
		case "Metadata":
			var zb0003 uint32
			zb0003, err = dc.ReadArrayHeader()
			if err != nil {
				err = msgp.WrapError(err, "Metadata")
				return
			}
			if cap(z.Metadata) >= int(zb0003) {
				z.Metadata = (z.Metadata)[:zb0003]
			} else {
				z.Metadata = make([]BatchJobKV, zb0003)
			}
			for za0002 := range z.Metadata {
				err = z.Metadata[za0002].DecodeMsg(dc)

            if (node2.metadata == null) {
                return metadata == null;
            }

            return metadata != null && metadata.toString().equals(node2.metadata.toString());
        } else {
            return super.equals(obj);
        }
    }

    @Override
    public int hashCode() {
        if (metadata == null) {
            return super.hashCode();
        }

Version 1.3 introduces changes to help with [faster metadata reads and updates](https://blog.min.io/minio-versioning-metadata-deep-dive/)

| Entry           | Encoding                    | Content
| ----------------|-----------------------------|----------------------------------------
| xlHeaderVersion | msgp uint                   | header version identifier
| xlMetaVersion   | msgp uint                   | metadata version identifier

    public void merge(ArtifactMetadata metadata) {
        ProjectArtifactMetadata m = (ProjectArtifactMetadata) metadata;
        if (!m.file.equals(file)) {
            throw new IllegalStateException("Cannot add two different pieces of metadata for: " + getKey());
        }
    }

    @Override
    public void merge(org.apache.maven.repository.legacy.metadata.ArtifactMetadata metadata) {

	// name is the full name of the object including prefixes
	name string
	// Metadata. If none is present it is not an object but only a prefix.
	// Entries without metadata will only be present in non-recursive scans.
	metadata []byte

	// cached contains the metadata if decoded.
	cached *xlMetaV2

	// Indicates the entry can be reused and only one reference to metadata is expected.
	reusable bool
}