TreeAdapter Provides the parent/child relationship information between pojos to derive a tree-structure. API TreeAdapter.java interface TreeAdapter<T> { Optional<T> parentOf(T value) (1) int childCountOf(T value) (2) Stream<T> childrenOf(T value) (3) } 1 parentOf(T) 2 childCountOf(T) 3 childrenOf(T) Members parentOf(T) childCountOf(T) childrenOf(T)