android/guava/src/com/google/common/graph/GraphBuilder.java
public <N1 extends N> ImmutableGraph.Builder<N1> immutable() {
    GraphBuilder<N1> castBuilder = cast();
    return new ImmutableGraph.Builder<>(castBuilder);
  }
public <N1 extends N> ImmutableGraph.Builder<N1> immutable() {
    GraphBuilder<N1> castBuilder = cast();
    return new ImmutableGraph.Builder<>(castBuilder);
  }
Returns an {@link ImmutableGraph#Builder} with the properties of this {@link GraphBuilder}.

<p>The returned builder can be used for populating an {@link ImmutableGraph}.

@since NEXT