JAVA 随机字符串生成方法

http://hi.baidu.com/yinfuqing666/blog/item/b9c3a0d21917e00e3af3cf28.html
http://hi.baidu.com/samuel_vong/blog/item/95471f7e2cdab33d0cd7dad1.html


使用 RandomStringUtils 类来生成随机码/随机数 http://www.oschina.net/code/snippet_12_576


实现方法一：
引用

public class RandomFileName {   
    /** 
     * 产生一个随机的字符串 
     *   
     * @param 字符串长度 
     * @return 
     */ 
    public static String getRandomString(int length) {   
        String base = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";   
        Random random = new Random();   
        StringBuffer sb = new StringBuffer();   
        for (int i = 0; i < length; i++) {   
            int number = random.nextInt(base.length());   
            sb.append(base.charAt(number));   
        }   
        return sb.toString();   
    }   

    public static void main(String[] args) {   
        System.out.println(RandomFileName.getRandomString(5));   
    }   
}

实现方法二：
引用

public class RandomFileName2 {   
    /** 
     * 产生一个随机的字符串 
     *   
     * @param 字符串长度 
     * @return 
     */ 
    public static String getRandomString(int length) {   
        Random random=new Random();   
        StringBuffer sb=new StringBuffer();   
        for(int i=0;i<length;i++){   
            int number=random.nextInt(3);   
            long result=0;   
            switch(number){   
                case 0:   
                    result = Math.round(Math.random()*25+65);   
                    sb.append(String.valueOf((char)result));   
                    break;   
                case 1:   
                    result = Math.round(Math.random()*25+97);   
                    sb.append(String.valueOf((char)result));   
                    break;   
                case 2:   
                    sb.append(String.valueOf(new Random().nextInt(10)));   
                    break;   
            }   
        }   
        return sb.toString();   
    }   
       
    public static void main(String[] args) {   
        System.out.println(RandomFileName2.getRandomString(10));   
    }   
}