把一个数组的组合全部列出

//把一个数组的组合全部列出
import java.util.*;
import java.io.*;

public class TestNum{
public static void main(String [] argument) throws Exception{
String [] array = new String [] {"1","2","3","4"};
listAll(Arrays.asList(array),"");
}

public static void listAll(List candidate,String prefix){

System.out.println(prefix);
for(int i= 0;i<candidate.size();i++){
List temp = new LinkedList(candidate);
listAll(temp,prefix + temp.remove(i));
}
}
}