随机生成字符串实现

给定一个字符集合，给定随机生成的字符串的长度，即可随机生成字符串；

比如{'a','.....,'z'}及长度5，则随机生成一个长度为5的字符串；

package xiazdong.util;

import java.util.Random;

/*根据给定的char集合，生成随机的字符串*/
public class StringWidthWeightRandom {
	private Random widthRandom = new Random();
	private int length;
	private char[] chars;
	private Random random = new Random();
	public StringWidthWeightRandom(char[] chars) {
		this.chars = chars;
	}
	
	//参数为生成的字符串的长度，根据给定的char集合生成字符串
	public String getNextString(int length){	
		
		char[] data = new char[length];
		
		for(int i = 0;i < length;i++){
			int index = random.nextInt(chars.length);
			data[i] = chars[index];
		}
		String s = new String(data);
		return s;
	}
	

}

测试代码：

package test.com.sap.prd.util;

import junit.framework.TestCase;

import org.junit.Test;

import com.sap.prd.util.StringWidthWeightRandom;

public class StringWidthWeightRandomTest extends TestCase {

	@Test
	public void testGetNextString()throws Exception{
		StringWidthWeightRandom random = new StringWidthWeightRandom(new char[]{'A','B','C','D','E','F','G'});
		
		for(int i=1;i<10;i++){
			System.out.println(random.getNextString(i));
		}
	}
}

结果：

F
CC
EGE
CADA
CFBFC
DBBCFE
BFEADFA
FDEEDACE
EEFFGFBEG