You can make objects comparable by implementing the java.lang.Comparable and java.util.Comparator interfaces.
Classes such as java.lang.String, java.util.Date, and primitive wrapper classes all implement java.lang.Comparable.
import java.util.Arrays; public class MainClass { public static void main(String[] args) { int[] intArray = new int[] { 5, 4, 3, 2, 1 }; Arrays.sort(intArray); for (int i : intArray) { System.out.println(i); } } }
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