public Integer getFirstStateId ( ) { Set < Integer > ids = states . inverse ( ) . keySet ( ) ; if ( ids . size ( ) < 1 ) { throw new IllegalStateException ( "There is no state defined." ) ; } Integer [ ] idsArray = new Integer [ ids . size ( ) ] ; Arrays . sort ( ids . toArray ( idsArray ) ) ; return idsArray [ 0 ] ; }
Get the ID of the state that has been defined first .