* Ensure encode throws NPE when passed a null buffer.
     */
    @Test
    @DisplayName("Encode with null buffer throws NullPointerException")
    public void testEncodeNullBuffer() throws NdrException {
        NdrHyper hyper = new NdrHyper(5L);
        assertThrows(NullPointerException.class, () -> hyper.encode(null));
    }

    /**
     * Ensure decode throws NPE when passed a null buffer.
     */
    @Test

        return treeRoot == null ? null : new MetadataGraph(treeRoot);
    }
    // ----------------------------------------------------------------------------
    public MetadataGraph getGraph(ArtifactScopeEnum scope)
            throws MetadataResolutionException, GraphConflictResolutionException {
        if (treeRoot == null) {
            return null;
        }

        if (conflictResolver == null) {

     * StringUtil.defaultString("aaa", "NULL") = "aaa"
     * StringUtil.defaultString("aaa", null)   = "aaa"
     * StringUtil.defaultString(null, null)    = null
     * </pre>
     *
     * @param str
     *            the string (can be <code>null</code>)
     * @param defaultStr
     *            the string to return if the argument is <code>null</code> (can be <code>null</code>)

    return (javaUtilOptional == null) ? null : fromNullable(javaUtilOptional.orElse(null));
  }

  /**
   * Returns the equivalent {@code java.util.Optional} value to the given {@code
   * com.google.common.base.Optional}, or {@code null} if the argument is null.
   *
   * <p>If {@code googleOptional} is known to be non-null, use {@code googleOptional.toJavaUtil()}
   * instead.
   *

    return rowKey != null && safeContainsKey(backingMap, rowKey);
  }

  @Override
  public boolean containsValue(@Nullable Object value) {
    return value != null && super.containsValue(value);
  }

  @Override
  public @Nullable V get(@Nullable Object rowKey, @Nullable Object columnKey) {
    return (rowKey == null || columnKey == null) ? null : super.get(rowKey, columnKey);
  }

    public String toString() {
        return "[" + (md == null ? "no metadata" : md.toString()) + "]";
    }

    // ---------------------------------------------------------------------
    private static int compareStrings(String s1, String s2) {
        if (s1 == null && s2 == null) {
            return 0;
        }

        if (s1 == null /* && s2 != null */) {
            return -1;
        }

        if (

        this.groupId = (groupId != null && !groupId.isEmpty()) ? groupId : null;
        this.artifactId = (artifactId != null && !artifactId.isEmpty()) ? artifactId : null;
        this.classifier = (classifier != null && !classifier.isEmpty()) ? classifier : null;
        this.extension = (extension != null && !extension.isEmpty()) ? extension : null;

        if (model == null) {
            return "";
        }

        String groupId = model.getGroupId();
        if (groupId == null && model.getParent() != null) {
            groupId = model.getParent().getGroupId();
        }

        String artifactId = model.getArtifactId();

        String version = model.getVersion();
        if (version == null && model.getParent() != null) {

        doUpdate(entity, null);
    }

    public void insertOrUpdate(CrawlingInfo entity) {
        doInsertOrUpdate(entity, null, null);
    }

    public void insertOrUpdate(CrawlingInfo entity, RequestOptionCall<IndexRequestBuilder> opLambda) {
        entity.asDocMeta().indexOption(opLambda);
        doInsertOrUpdate(entity, null, null);
    }

        doUpdate(entity, null);
    }

    public void insertOrUpdate(ElevateWord entity) {
        doInsertOrUpdate(entity, null, null);
    }

    public void insertOrUpdate(ElevateWord entity, RequestOptionCall<IndexRequestBuilder> opLambda) {
        entity.asDocMeta().indexOption(opLambda);
        doInsertOrUpdate(entity, null, null);
    }

    public void delete(ElevateWord entity) {