在java中怎么把字节数组转换成二进制字符串

public class Test {
public static void main(String args[])   {
String ZERO="00000000";
String x ="lalala";
byte[]   bs   =   x.getBytes();
for   (int i = 0;i<bs.length;i++)   {
String   s   =   Integer.toBinaryString(bs[i]);
if   (s.length()   >
8)   {
s   =   s.substring(s.length()   -   8);
}   else   if   (s.length()
<   8)   {
s   =   ZERO.substring(s.length())   +   s;
}
System.out.println(s);
}
}
}