Java-随机数工具类

 import java.util.Random;
 import java.util.concurrent.ThreadLocalRandom;
 import org.apache.commons.lang3.RandomUtils;
 import org.apache.commons.math3.random.RandomDataGenerator;

 /**
  * @ClassName: RandomUtil
  * @Description: 随机数工具类
  * (分别使用java.util.Random、Apache Common Math3、Apache Common Lang3、TreadLocalRandom)
  */
 public class RandomUtil {
     /**
      * 随机数Int的生成
      */
     // 随机数生成无边界的Int
     public static int getRandomForIntegerUnbounded() {
         int intUnbounded = new Random().nextInt();
         System.out.println(intUnbounded);
         return intUnbounded;
     }

     // 生成有边界的Int
     public static int getRandomForIntegerBounded(int min, int max) {
         int intBounded = min + ((int) (new Random().nextFloat() * (max - min)));
         System.out.println(intBounded);
         return intBounded;
     }

     // 包含1而不包含10
     // 使用Apache Common Math3来生成有边界的Int
     public static int getRandomForIntegerBounded2(int min, int max) {
         int intBounded = new RandomDataGenerator().nextInt(min, max);
         System.out.println(intBounded);
         return intBounded;
     }

     // 包含1且包含10
     // 使用Apache Common Lang3的工具类来生成有边界的Int
     public static int getRandomForIntegerBounded3(int min, int max) {
         int intBounded = RandomUtils.nextInt(min, max);
         System.out.println(intBounded);
         return intBounded;
     }

     // 使用TreadLocalRandom来生成有边界的Int,包含min而不包含max
     public static int getRandomForIntegerBounded4(int min, int max) {
         int threadIntBound = ThreadLocalRandom.current().nextInt(min, max);
         System.out.println(threadIntBound);
         return threadIntBound;
     }

     /**
      * 随机数Long的生成
      */
     // 随机数生成无边界的Long
     public static long getRandomForLongUnbounded() {
         long unboundedLong = new Random().nextLong();
         System.out.println(unboundedLong);
         return unboundedLong;
     }

     // 因为Random类使用的种子是48bits，所以nextLong不能返回所有可能的long值，long是64bits。
     // 使用Random生成有边界的Long
     public static long getRandomForLongBounded(long min, long max) {
         long rangeLong = min + (((long) (new Random().nextDouble() * (max - min))));
         System.out.println(rangeLong);
         return rangeLong;
     }

     // 使用Apache Commons Math3来生成有边界的Long(RandomDataGenerator类提供的生成随机数的方法)
     public static long getRandomForLongBounded2(long min, long max) {
         long rangeLong = new RandomDataGenerator().nextLong(min, max);
         System.out.println(rangeLong);
         return rangeLong;
     }

     // 使用Apache Commons Lang3的工具类来生成有边界的Long(RandomUtils提供了对java.util.Random的补充)
     public static long getRandomForLongBounded3(long min, long max) {
         long longBounded = RandomUtils.nextLong(min, max);
         System.out.println(longBounded);
         return longBounded;
     }

     // 使用ThreadLocalRandom生成有边界的Long
     public static long getRandomForLongBounded4(long min, long max) {
         long threadLongBound = ThreadLocalRandom.current().nextLong(min, max);
         System.out.println(threadLongBound);
         return threadLongBound;
     }

     /**
      * 随机数Float的生成
      */
     // 随机数Float的生成生成0.0-1.0之间的Float随机数
     public static float getRandomForFloat0To1() {
         float floatUnbounded = new Random().nextFloat();
         System.out.println(floatUnbounded);
         return floatUnbounded;
     }

     // 以上只会生成包含0.0而不包括1.0的float类型随机数生成有边界的Float随机数
     public static float getRandomForFloatBounded(float min, float max) {
         float floatBounded = min + new Random().nextFloat() * (max - min);
         System.out.println(floatBounded);
         return floatBounded;
     }

     // 使用Apache Common Math来生成有边界的Float随机数
     public static float getRandomForFloatBounded2(float min, float max) {
         float randomFloat = new RandomDataGenerator().getRandomGenerator().nextFloat();
         float generatedFloat = min + randomFloat * (max - min);
         System.out.println(generatedFloat);
         return generatedFloat;
     }

     // 使用Apache Common Lang来生成有边界的Float随机数
     public static float getRandomForFloatBounded3(float min, float max) {
         float generatedFloat = RandomUtils.nextFloat(min, max);
         System.out.println(generatedFloat);
         return generatedFloat;
     }

     // 使用ThreadLocalRandom生成有边界的Float随机数
     // ThreadLocalRandom类没有提供

     /**
      * 随机数Double的生成
      */
     // 生成0.0d-1.0d之间的Double随机数
     public static double getRandomForDouble0To1() {
         double generatorDouble = new Random().nextDouble();
         System.out.println(generatorDouble);
         return generatorDouble;
     }

     // 与Float相同，以上方法只会生成包含0.0d而不包含1.0d的随机数生成带有边界的Double随机数
     public static double getRandomForDoubleBounded(double min, double max) {
         double boundedDouble = min + new Random().nextDouble() * (max - min);
         System.out.println(boundedDouble);
         return boundedDouble;
     }

     // 使用Apache Common Math来生成有边界的Double随机数
     public static double getRandomForDoubleBounded2(double min, double max) {
         double boundedDouble = new RandomDataGenerator().getRandomGenerator().nextDouble();
         double generatorDouble = min + boundedDouble * (max - min);
         System.out.println(generatorDouble);
         return generatorDouble;
     }

     // 使用Apache Common Lang生成有边界的Double随机数
     public static double getRandomForDoubleBounded3(double min, double max) {
         double generatedDouble = RandomUtils.nextDouble(min, max);
         System.out.println(generatedDouble);
         return generatedDouble;
     }

     // 使用ThreadLocalRandom生成有边界的Double随机数
     public static double getRandomForDoubleBounded4(double min, double max) {
         double generatedDouble = ThreadLocalRandom.current().nextDouble(min, max);
         System.out.println(generatedDouble);
         return generatedDouble;
     }
 }

 //相关依赖
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-lang3</artifactId>
             <version>3.3.2</version>
         </dependency>
         <!-- commons-math3 -->
         <dependency>
             <groupId>org.apache.commons</groupId>
             <artifactId>commons-math3</artifactId>
             <version>3.6.1</version>
         </dependency>