java - Sorting Polymorphic Arrays -

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lets have 3 classes (passenger,pilot,stewardess) inherit abstract class called persons, , in array of persons save many of these objects 3 classes defined, want sort objects inside array of persons in following order:

-all objects class passenger

-all objects class pilot

-all objects class stewardess

is there way achieve without arraylists?

arrays.sort(personarray, new comparator<person>() {      @override     public int compare(person p1, person p2) {         int person1index = getorderindex(p1);         int person2index = getorderindex(p2);          if (person1index < person2index) {             return -1;         } else if (person1index > person2index) {             return 1;         } else {             return 0;         }     }      private int getorderindex(person p) {         if (p == null) {             return 0;         } else if (p instanceof passenger) {             return 1;         } else if (p instanceof pilot) {             return 2;         } else if (p instanceof stewardess) {             return 3;         } else {             throw new runtimeexception("unexpected person type: " + p.getclass().getname());         }     } });

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