Java新手请教:如果产生一个由100个随机数字或英文字符组成字符串?
诚心求教?
------解决方案--------------------
/**
		   * 产生随机字符串
		   * */
		private static Random randGen = null;
		private static char[] numbersAndLetters = null;
		public static final String randomString(int length) {
		         if (length < 1) {
		             return null;
		         }
		         if (randGen == null) {
		                randGen = new Random();
		                numbersAndLetters = ("0123456789abcdefghijklmnopqrstuvwxyz" +
		                   "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();
		                  //numbersAndLetters = ("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ").toCharArray();
		                 }
		         char [] randBuffer = new char[length];
		         for (int i=0; i<randBuffer.length; i++) {
		             randBuffer[i] = numbersAndLetters[randGen.nextInt(71)];
		          //randBuffer[i] = numbersAndLetters[randGen.nextInt(35)];
		         }
		         return new String(randBuffer);
		}		
		//调用此方法randomString(int),int是字符串的长度,即可产生指定长度的随机字符串。
------解决方案--------------------我的一个简单的随机数
http://yijianfengvip.blog.163.com/blog/static/1752734322011730113047841/