inserts a key into the heirarchy . used during deserialization : you normally do n't need this . keys must be inserted in order . concode_field_sep int BIP32_STANDARDISATION_TIME_SECS concode_elem_sep Map<ImmutableList<ChildNumber>,DeterministicKey> keys concode_elem_sep ImmutableList<ChildNumber> rootPath concode_elem_sep Map<ImmutableList<ChildNumber>,ChildNumber> lastChildNumbers concode_field_sep ChildNumber getNextChildNumberToDerive concode_elem_sep DeterministicKey get concode_elem_sep DeterministicKey getRootKey concode_elem_sep DeterministicKey deriveChild concode_elem_sep DeterministicKey deriveChild concode_elem_sep int getNumChildren concode_elem_sep DeterministicKey deriveNextChild