java随机数生成

import java.util.Random;

public class RandomExample {
    public static void main(String[] args) {
        Random rand = new Random();
        int randomInt = rand.nextInt(100); // 生成0到99之间的随机整数
        System.out.println("Random Integer: " + randomInt);
    }
}

import java.security.SecureRandom;

public class SecureRandomExample {
    public static void main(String[] args) {
        SecureRandom secureRandom = new SecureRandom();
        byte[] bytes = new byte[20];
        secureRandom.nextBytes(bytes); // 生成20字节的随机数据
        System.out.println("Secure Random Bytes: " + bytes);
    }
}

import java.util.concurrent.ThreadLocalRandom;

public class ThreadLocalRandomExample {
    public static void main(String[] args) {
        int randomInt = ThreadLocalRandom.current().nextInt(100);
        System.out.println("Thread-Safe Random Integer: " + randomInt);
    }
}