随机生成字符串实现

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;
}

}

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));
}
}
}

F
CC
EGE
CADA
CFBFC
DBBCFE
BFEADFA
FDEEDACE
EEFFGFBEG