java custom comparator example

gistfile1.java

import java.util.Arrays;
import java.util.Comparator;
 
class Dog{
	int size;	
	public Dog(int s){
		size = s;
	}
}
 
class DogSizeComparator implements Comparator<Dog>{
 
	@Override
	public int compare(Dog o1, Dog o2) {
		return o1.size - o2.size;
	}
}
 
public class ArraySort {
 
	public static void main(String[] args) {
		Dog d1 = new Dog(2);
		Dog d2 = new Dog(1);
		Dog d3 = new Dog(3);
 
		Dog[] dogArray = {d1, d2, d3};
		printDogs(dogArray);
 
		Arrays.sort(dogArray, new DogSizeComparator());	
		printDogs(dogArray);
	}
 
	public static void printDogs(Dog[] dogs){
		for(Dog d: dogs)
			System.out.print(d.size + " " );
 
		System.out.println();
	}
}