public int compareTo ( final OMVRBTreeEntry < K , V > o ) { if ( o == null ) return 1 ; if ( o == this ) return 0 ; if ( getSize ( ) == 0 ) return - 1 ; if ( o . getSize ( ) == 0 ) return 1 ; if ( tree . comparator != null ) return tree . comparator . compare ( getFirstKey ( ) , o . getFirstKey ( ) ) ; return ( ( Comparable < K > ) getFirstKey ( ) ) . compareTo ( o . getFirstKey ( ) ) ; }
Compares two nodes by their first keys .