1 package com.jdk7.chapter3;
2
3 import java.util.Random;
4
5 /**
6 * java.util.Math.random()随机生成[0,1]的浮点数
7 * @author Administrator
8 *
9 */
10 public class Random1 {
11 public static void main(String[] args) {
12 System.out.println("随机生成[0,1]的浮点数"+
Math.random());
13 System.out.println("随机生成[0,1]的浮点数"+
Math.random());
14
15 System.out.println("随机生成int类型的数: "+(
new Random()).nextInt());
16 System.out.println("随机生成[0,30]的int类型的数: "+(
new Random()).nextInt(30
));
17 System.out.println("随机生成[5,30]的int类型的数: "+(5+(
new Random()).nextInt(30
)));
18
19 System.out.println("随机生成[0,1] float类型的数: "+(
new Random()).nextFloat());
20 System.out.println("随机生成float类型的数后转换为int类型: "+(
int) ((
new Random()).nextFloat()*100
));
21
22 System.out.println("随机生成long类型的数: "+(
new Random()).nextLong());
23
24 System.out.println("随机生成[0,1] double类型的数: "+(
new Random()).nextDouble());
25
26 System.out.println("随机生成gaussian类型的数: "+(
new Random()).nextGaussian());
27
28 System.out.println("随机生成boolean类型的数: "+(
new Random()).nextBoolean());
29
30 //声明Random对象后,如果随机数种子相同,则生成完全一致的随机数
31 Random r1 =
new Random(20
);
32 for(
int i=0;i<5;i++
){
33 System.out.print("r1: "+r1.nextInt(20)+" "
);
34 }
35 System.out.println();
36
37 Random r2 =
new Random(20
);
38 for(
int i=0;i<5;i++
){
39 System.out.print("r2: "+r2.nextInt(20)+" "
);
40 }
41 System.out.println();
42 }
43 }
44
45 执行结果:
46 随机生成[0,1]的浮点数0.7475166373371607
47 随机生成[0,1]的浮点数0.5828554127694848
48 随机生成int类型的数: -1617055350
49 随机生成[0,30]的int类型的数: 6
50 随机生成[5,30]的int类型的数: 12
51 随机生成[0,1] float类型的数: 0.08533013
52 随机生成float类型的数后转换为int类型: 68
53 随机生成long类型的数: -7518776773801746754
54 随机生成[0,1] double类型的数: 0.7550215139757701
55 随机生成gaussian类型的数: 0.04748439140005734
56 随机生成boolean类型的数:
true
57 r1: 13 r1: 16 r1: 1 r1: 1 r1: 5
58 r2: 13 r2: 16 r2: 1 r2: 1 r2: 5
转载于:https://www.cnblogs.com/celine/p/8305673.html