文中的Random即：java.util.Random，ThreadLocalRandom 即：java.util.concurrent.ThreadLocalRandomSecureRandom即：java.security.SecureRandomQ：Random是不是线程安全的？A：Random是线程安全的，但是多线程下可能性能比较低。参考：http://docs.oracle.com/javase/7/docs/api/java/util/Random.htmlhttp://stackoverflow.com/questions/5819638/is-random-class-thread-safeQ：ThreadLocalRandom为什么这么快？A：其实这个看下...
生成随机数的几种方法： Math.random()一随机数 java.util.Random伪随机数（线性同余法生成） java.util.concurrent.ThreadLocalRandom 工具类 java.security.SecureRandom 真随机数 Apache Commons-Lang 包中的 RandomStringUtils 类一. Math.random()Math.random()：（产生[0,1)范围的double随机数）publicstaticdouble random() {Random rnd = randomNumberGenerator;if (rnd == null) rnd = initRNG();return r...
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1、Random random=new Random(); random.nextInt(10);int randNumber = rand.nextInt(MAX - MIN + 1) + MIN;https://www.cnblogs.com/weink1215/p/4433790.html2、Math类的random()方法可以生成大于等于0.0、小于1.0的double型随机数。https://blog.csdn.net/qq_22195761/article/details/70313837原文：https://www.cnblogs.com/sangong/p/9576512.html
package demo;import java.util.Random;publicclass math {publicstaticvoid main(String[] args) {String[] operate=new String[]{"+","-","×","÷"};int[] numbers=newint[1000];for(int i=1;i<=1000;i++){numbers[i-1]=i;}Random r=new Random();for(int i=0;i<300;i++){System.out.println(numbers[r.nextInt(1000)]+operate[r.nextInt(4)]+numbers[r.nextInt(1000)]+"=");}}} 原文：http://www.cnblogs.com/lippman/p/6526860....
private static String getRandomChinese(){Random random = new Random();int code1,code2,code3,code4;//分别代表四个位码String checkCode = "";String[] rBase = {"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"};code1 = random.nextInt(3) +11;String str_r1 = rBase[code1];//获得第一个位码if(code1 == 13) {code2 = random.nextInt(7);}else {code2 = random.nextInt(16);}String str_r2 = rBase[code...
Random 类作为JAVA中用于产生的随机数 ，new Random(10) ：10是种子数。注意：Random 的一个特点是：相同种子数的Random对象，对应相同次数生成的随机数字是完全相同的 验证代码： Random r1 = new Random(10); Random r2 = new Random(10); for(int i = 0;i < 4;i++){ System.out.println(r1.nextInt(5)); }System.out.println("++++++++++++++++++++++"); for(int i = 0...
package lovo;import java.util.HashMap; import java.util.Map; /** * 随机生成中文姓名，性别，Email，手机号，住址 * @author Quentin */publicclass SuperRandom { publicstatic String base = "abcdefghijklmnopqrstuvwxyz0123456789"; privatestatic String firstName="赵钱孙李周吴郑王冯陈褚卫蒋沈韩杨朱秦尤许何吕施张孔曹严华金魏陶姜戚谢邹喻柏水窦章云苏潘葛奚范彭郎鲁韦昌马苗凤花方俞任袁柳酆鲍史唐费廉岑薛雷...
package Example;/* 随机产生10以内的两个整数number1和number2，显示算式， 例如“What is 7 plus 9 ?”，输入答案后，提示答案是否正确。 产生随机数的方法：System.currentTimeMillis()， 这个方法获得系统当前时间到1970.1.1 00:00:00的时间差值， 是一个以毫秒为单位的long类型的值。 */import java.util.Scanner; //Scanner语句需要public class plus_2_5 { public static void main(String[] args) { // TODO A...
Java随机生成6位字符串import java.util.Random;/*** @author wangan*/ public class SignUtil {private static final String BASIC = "123456789qwertyuiopasdfghjklzxcvbnm";public static String random(){char[] basicArray = BASIC.toCharArray();Random random = new Random();char[] result = new char[6];for (int i = 0; i < result.length; i++) {int index = random.nextInt(100) % (basicArray.length);result[i] = ba...
/**八种基本数据类型booleanbyteshortintlongcharfloatdouble */publicclass test1{publicstaticvoid main(String[] args){long g = 1000L;float f = 3.14F;double d = 10.12345d;} } import java.util.Scanner;publicclass Main {publicstaticvoid main(String[] args) {Scanner input = new Scanner(System.in);int a = input.nextInt();int b = input.nextInt();System.out.println("a+b = "+(a+b));} } import java.util.Rando...
import java.util.Iterator; import java.util.Scanner; import java.util.TreeSet;public class RandomDataSort {public static void main(String[] args) {Scanner scan = new Scanner(System.in);int num = scan.nextInt();TreeSet<Integer> tSet = new TreeSet<Integer>();while (num != 0) {tSet.add(scan.nextInt());num--;}Iterator<Integer> it = tSet.iterator();while (it.hasNext()) {System.out.println(it.next());}}...
方法1(数据类型)(最小值+Math.random()*(最大值-最小值+1)) 例:(int)(1+Math.random()*(10-1+1)) 从1到10的int型随数方法2获得随机数 for (int i=0;i<30;i++) {System.out.println((int)(1+Math.random()*10));}(int)(1+Math.random()*10) 通过java.Math包的random方法得到1-10的int随机数 公式是:最小值---最大值（整数）的随机数 （类型）最小值+Math.random()*最大值方法3Random ra =new Random(); for (int i=0;i<30;i++) {Sys...
import java.util.Random;public class SuiJiShu {public static void main(String[] args) { Random random=new Random(); int [] hong={1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33}; int [] lan={1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}; for(int i=0;i<6;i++){ System.out.print(hong[random.nextInt(33)]+","); } System.out.println(); for (int i = 0;...
【生成随机数序列】我们只能利用Math.random()方法只能生成一个在[0,1)之间的double类型浮点数。但如果我们想要生成[min, max]之间的随机整数时该怎么办呢？此时可以用：int rdmNum = (int) (Math.random() * (max + 1 - min) + min);【随机数生产器(存在重复随机数)】publicstaticint[] createRandomArray(int arrLength, int rdmMin, int rdmMax) { //根据所给数组长度，生成所要的数组int[] arr = newint[arrLength]; /...