Java：通过Random获取伪随机数

Random获取随机数

package com.example.demo;

import java.util.Random;

public class RandomDemo {
    public static void main(String[] args) {
        Random random = new Random();

        // 指定边界 [0, bound)
        System.out.println(random.nextInt(10));
        // 8

        // [0, 1)
        System.out.println(Math.random());
        // 0.4743026139690609
    }
}

更多随机数据获取方法

用到的依赖

    commons-lang
    commons-lang
    2.6

示例

package com.demo.random;

import org.apache.commons.lang.RandomStringUtils;

import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Random;
import java.util.concurrent.ThreadLocalRandom;

public class RandomDemo {
    public static void main(String[] args) throws NoSuchAlgorithmException {
        // 1、Random
        Random random = new Random();
        System.out.println(random.nextDouble());


        // 2、Math.random
        System.out.println(Math.random());


        // 3、ThreadLocalRandom
        System.out.println(ThreadLocalRandom.current().nextDouble());


        // 4、SecureRandom
        SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
        System.out.println(secureRandom.nextDouble());


        // 5、RandomStringUtils
        String result = RandomStringUtils.random(64);
        System.out.println(result);

        // 长度为64位的字符串
        result = RandomStringUtils.randomAlphabetic(64);
        System.out.println(result);

        // 32位ascii码
        result = RandomStringUtils.randomAscii(32);
        System.out.println(result);

        // 指定字符数组
        result = RandomStringUtils.random(32, "qw32rfHIJk9iQ8Ud7h0X");
        System.out.println(result);

        /**
         * 0.6842526472648046
         * 0.968969349495142
         * 0.27962124767826213
         * 0.012367070163319283
         * 汕真庣뉔햯殫腍ꡊꁝ㨂Ǒ蒐霫瓯䟤ሠ漧ᎊ򜐍끘෦𧆕惘횕緛暑⫺ꟻ䟻↕㽱륪鶋㛿ᔑ㓇䢙뿍鼗ꦡ첡缹﷪濎릅솣떽裴ﱆ뙠曜蘝せⶏ潻➣▨澜채
         * niSaTPTkUfrdqjcgFbZcyAqdGsnZQKoKSWpUxYSffMDiNBMVBcGfkxGOphVkAhMe
         * :xB__?hx/W,,?7bEdr@~E4GjLh6yxp0U
         * I80QH8Uffwkh8r03ddrrHHUk8w9h0rJw
         */
    }
}

参考 Java 生成随机数的 5 种方式，你知道几种？