RandomUtil (vjkit 1.0.8 API)

java.lang.Object
- com.vip.vjtools.vjkit.number.RandomUtil

```
public class RandomUtil
extends Object
```
随机数工具集. 1. 获取无锁的ThreadLocalRandom, 性能较佳的SecureRandom 2. 保证没有负数陷阱，也能更精确设定范围的nextInt/nextLong/nextDouble (copy from Common Lang RandomUtils，但默认使用性能较优的ThreadLocalRandom，并可配置其他的Random) 3. 随机字符串 (via Common Lang RandomStringUtils)

Author:

calvin

Constructor Summary

Constructors
Constructor and Description

RandomUtil()

Constructors
Constructor and Description
`RandomUtil()`

Method Summary

Methods
Modifier and Type	Method and Description
`static double`	`nextDouble()` 返回0-之间的double, 使用ThreadLocalRandom
`static double`	`nextDouble(double max)` 返回0-max之间的double, 使用ThreadLocalRandom 注意：与JDK默认返回0-1的行为不一致.
`static double`	`nextDouble(double min, double max)` 返回min-max之间的double,ThreadLocalRandom
`static double`	`nextDouble(Random random)` 返回0-Double.MAX之间的double
`static double`	`nextDouble(Random random, double max)` 返回0-max之间的double
`static double`	`nextDouble(Random random, double min, double max)` 返回min-max之间的double
`static int`	`nextInt()` 返回0到Intger.MAX_VALUE的随机Int, 使用ThreadLocalRandom.
`static int`	`nextInt(int max)` 返回0到max的随机Int, 使用ThreadLocalRandom.
`static int`	`nextInt(int min, int max)` 返回min到max的随机Int, 使用ThreadLocalRandom.
`static int`	`nextInt(Random random)` 返回0到Intger.MAX_VALUE的随机Int, 可传入ThreadLocalRandom或SecureRandom
`static int`	`nextInt(Random random, int max)` 返回0到max的随机Int, 可传入SecureRandom或ThreadLocalRandom
`static int`	`nextInt(Random random, int min, int max)` 返回min到max的随机Int,可传入SecureRandom或ThreadLocalRandom.
`static long`	`nextLong()` 返回0－Long.MAX_VALUE间的随机Long, 使用ThreadLocalRandom.
`static long`	`nextLong(long max)` 返回0－max间的随机Long, 使用ThreadLocalRandom.
`static long`	`nextLong(long min, long max)` 返回min－max间的随机Long, 使用ThreadLocalRandom.
`static long`	`nextLong(Random random)` 返回0－Long.MAX_VALUE间的随机Long, 可传入SecureRandom或ThreadLocalRandom
`static long`	`nextLong(Random random, long max)` 返回0-max间的随机Long, 可传入SecureRandom或ThreadLocalRandom
`static long`	`nextLong(Random random, long min, long max)` 返回min-max间的随机Long,可传入SecureRandom或ThreadLocalRandom.
`static String`	`randomAsciiFixLength(int length)` 随机ASCII字符(含字母，数字及其他符号)，固定长度
`static String`	`randomAsciiFixLength(Random random, int length)` 随机ASCII字符(含字母，数字及其他符号)，固定长度
`static String`	`randomAsciiRandomLength(int minLength, int maxLength)` 随机ASCII字符(含字母，数字及其他符号)，随机长度
`static String`	`randomAsciiRandomLength(Random random, int minLength, int maxLength)` 随机ASCII字符(含字母，数字及其他符号)，随机长度
`static String`	`randomLetterFixLength(int length)` 随机字母，固定长度
`static String`	`randomLetterFixLength(Random random, int length)` 随机字母，固定长度
`static String`	`randomLetterRandomLength(int minLength, int maxLength)` 随机字母，随机长度
`static String`	`randomLetterRandomLength(Random random, int minLength, int maxLength)` 随机字母，随机长度
`static String`	`randomStringFixLength(int length)` 随机字母或数字，固定长度
`static String`	`randomStringFixLength(Random random, int length)` 随机字母或数字，固定长度
`static String`	`randomStringRandomLength(int minLength, int maxLength)` 随机字母或数字，随机长度
`static String`	`randomStringRandomLength(Random random, int minLength, int maxLength)` 随机字母或数字，随机长度
`static SecureRandom`	`secureRandom()` SecureRandom使用性能更好的SHA1PRNG, Tomcat的sessionId生成也用此算法.
`static Random`	`threadLocalRandom()` 返回无锁的ThreadLocalRandom

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - RandomUtil
```
public RandomUtil()
```
- Method Detail
  - threadLocalRandom
```
public static Random threadLocalRandom()
```
    返回无锁的ThreadLocalRandom
  - secureRandom
```
public static SecureRandom secureRandom()
```
    SecureRandom使用性能更好的SHA1PRNG, Tomcat的sessionId生成也用此算法. 但JDK7中，需要在启动参数加入 -Djava.security=file:/dev/./urandom （中间那个点很重要）详见：《SecureRandom的江湖偏方与真实效果》http://calvin1978.blogcn.com/articles/securerandom.html
  - nextInt
```
public static int nextInt()
```
    返回0到Intger.MAX_VALUE的随机Int, 使用ThreadLocalRandom.
  - nextInt
```
public static int nextInt(Random random)
```
    返回0到Intger.MAX_VALUE的随机Int, 可传入ThreadLocalRandom或SecureRandom
  - nextInt
```
public static int nextInt(int max)
```
    返回0到max的随机Int, 使用ThreadLocalRandom.
  - nextInt
```
public static int nextInt(Random random,
          int max)
```
    返回0到max的随机Int, 可传入SecureRandom或ThreadLocalRandom
  - nextInt
```
public static int nextInt(int min,
          int max)
```
    返回min到max的随机Int, 使用ThreadLocalRandom. min必须大于0.
  - nextInt
```
public static int nextInt(Random random,
          int min,
          int max)
```
    返回min到max的随机Int,可传入SecureRandom或ThreadLocalRandom. min必须大于0. JDK本身不具有控制两端范围的nextInt，因此参考Commons Lang RandomUtils的实现, 不直接复用是因为要传入Random实例
    
    See Also:
    org.apache.commons.lang3.RandomUtils#nextInt(long, long)
  - nextLong
```
public static long nextLong()
```
    返回0－Long.MAX_VALUE间的随机Long, 使用ThreadLocalRandom.
  - nextLong
```
public static long nextLong(Random random)
```
    返回0－Long.MAX_VALUE间的随机Long, 可传入SecureRandom或ThreadLocalRandom
  - nextLong
```
public static long nextLong(long max)
```
    返回0－max间的随机Long, 使用ThreadLocalRandom.
  - nextLong
```
public static long nextLong(Random random,
            long max)
```
    返回0-max间的随机Long, 可传入SecureRandom或ThreadLocalRandom
  - nextLong
```
public static long nextLong(long min,
            long max)
```
    返回min－max间的随机Long, 使用ThreadLocalRandom. min必须大于0.
  - nextLong
```
public static long nextLong(Random random,
            long min,
            long max)
```
    返回min-max间的随机Long,可传入SecureRandom或ThreadLocalRandom. min必须大于0. JDK本身不具有控制两端范围的nextLong，因此参考Commons Lang RandomUtils的实现, 不直接复用是因为要传入Random实例
    
    See Also:
    RandomUtils.nextLong(long, long)
  - nextDouble
```
public static double nextDouble()
```
    返回0-之间的double, 使用ThreadLocalRandom
  - nextDouble
```
public static double nextDouble(Random random)
```
    返回0-Double.MAX之间的double
  - nextDouble
```
public static double nextDouble(double max)
```
    返回0-max之间的double, 使用ThreadLocalRandom 注意：与JDK默认返回0-1的行为不一致.
  - nextDouble
```
public static double nextDouble(Random random,
                double max)
```
    返回0-max之间的double
  - nextDouble
```
public static double nextDouble(double min,
                double max)
```
    返回min-max之间的double,ThreadLocalRandom
  - nextDouble
```
public static double nextDouble(Random random,
                double min,
                double max)
```
    返回min-max之间的double
  - randomStringFixLength
```
public static String randomStringFixLength(int length)
```
    随机字母或数字，固定长度
  - randomStringFixLength
```
public static String randomStringFixLength(Random random,
                           int length)
```
    随机字母或数字，固定长度
  - randomStringRandomLength
```
public static String randomStringRandomLength(int minLength,
                              int maxLength)
```
    随机字母或数字，随机长度
  - randomStringRandomLength
```
public static String randomStringRandomLength(Random random,
                              int minLength,
                              int maxLength)
```
    随机字母或数字，随机长度
  - randomLetterFixLength
```
public static String randomLetterFixLength(int length)
```
    随机字母，固定长度
  - randomLetterFixLength
```
public static String randomLetterFixLength(Random random,
                           int length)
```
    随机字母，固定长度
  - randomLetterRandomLength
```
public static String randomLetterRandomLength(int minLength,
                              int maxLength)
```
    随机字母，随机长度
  - randomLetterRandomLength
```
public static String randomLetterRandomLength(Random random,
                              int minLength,
                              int maxLength)
```
    随机字母，随机长度
  - randomAsciiFixLength
```
public static String randomAsciiFixLength(int length)
```
    随机ASCII字符(含字母，数字及其他符号)，固定长度
  - randomAsciiFixLength
```
public static String randomAsciiFixLength(Random random,
                          int length)
```
    随机ASCII字符(含字母，数字及其他符号)，固定长度
  - randomAsciiRandomLength
```
public static String randomAsciiRandomLength(int minLength,
                             int maxLength)
```
    随机ASCII字符(含字母，数字及其他符号)，随机长度
  - randomAsciiRandomLength
```
public static String randomAsciiRandomLength(Random random,
                             int minLength,
                             int maxLength)
```
    随机ASCII字符(含字母，数字及其他符号)，随机长度

Class RandomUtil

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RandomUtil

Method Detail

threadLocalRandom

secureRandom

nextInt

nextInt

nextInt

nextInt

nextInt

nextInt

nextLong

nextLong

nextLong

nextLong

nextLong

nextLong

nextDouble

nextDouble

nextDouble

nextDouble

nextDouble

nextDouble

randomStringFixLength

randomStringFixLength

randomStringRandomLength

randomStringRandomLength

randomLetterFixLength

randomLetterFixLength

randomLetterRandomLength

randomLetterRandomLength

randomAsciiFixLength

randomAsciiFixLength

randomAsciiRandomLength

randomAsciiRandomLength