question: public DeterministicKey ( ImmutableList < ChildNumber > childNumberPath , byte [ ] chainCode , LazyECPoint publicAsPoint , @ Nullable DeterministicKey parent , int depth , int parentFingerprint ) { super ( null , compressPoint ( checkNotNull ( publicAsPoint ) ) ) ; checkArgument ( chainCode . length == 32 ) ; this . parent = parent ; this . childNumberPath = checkNotNull ( childNumberPath ) ; this . chainCode = Arrays . copyOf ( chainCode , chainCode . length ) ; this . depth = depth ; this . parentFingerprint = ascertainParentFingerprint ( parent , parentFingerprint ) ; }
target:  Constructs a key from its components, including its public key data and possibly-redundant information about its parent key.  Invoked when deserializing, but otherwise not something that you normally should use.