public class RandomIntegers
1: //RandomIntegers.java
3: import java.util.Arrays;
4: import java.util.Random;
6: public class RandomIntegers
7: {
8: public static void main(String args[])
9: {
10: //Print ten random two-digit integers in reverse sorted order
12: Random random = new Random();
13: //random.setSeed(1); //Activate to get same values on each run
15: System.out.println("\n=============");
16: System.out.println("Using Java 7: ");
17: Integer[] ranArray = new Integer[10];
18: for (int i = 0; i < 10; i++)
19: {
20: ranArray[i] = 10 + random.nextInt(90); //Values are boxed
21: }
22: Arrays.sort(ranArray, (a, b) -> b.compareTo(a)); //Or (a, b) -> b - a
23: for (int i = 0; i < 10; i++)
24: {
25: System.out.println(ranArray[i]);
26: }
28: System.out.println("\n=============");
29: System.out.println("Using Java 8: ");
30: random.ints(10, 100)
31: .limit(10)
32: .boxed()
33: //Without this we have to use sorted() from IntStream
34: //which does not have a version that takes a parameter.
35: //With this we are using sorted() from Stream.
36: .sorted((a, b) -> b - a)
37: .forEach(System.out::println);
38: }
39: }
40: /* Output:
41: Using Java 7:
42: 89
43: 77
44: 70
45: 70
46: 69
47: 62
48: 61
49: 37
50: 15
51: 13
53: =============
54: Using Java 8:
55: 81
56: 71
57: 65
58: 63
59: 55
60: 40
61: 40
62: 37
63: 29
64: 24
65: */