Write a method that accepts a string and then prints all pos

Write a method that accepts a string and then prints all possible combinations of rotations of that word.

Ex: for the string \"test\" the rotation are estt, stte, ttes.

Using Java language , thanks a lot

Solution

public class PermTest {

public static void main(String[] args) throws Exception {

String str = \"test\";

StringBuffer strBuf = new StringBuffer(str);

doPerm(strBuf,str.length());

}

private static void doPerm(StringBuffer str, int index){

if(index <= 0)

System.out.println(str);           

else { //recursively solve this by placing all other chars at current first pos

doPerm(str, index-1);

int currPos = str.length()-index;

for (int i = currPos+1; i < str.length(); i++) {//start swapping all other chars with current first char

swap(str,currPos, i);

doPerm(str, index-1);

swap(str,i, currPos);//restore back my string buffer

}

}

}

private static void swap(StringBuffer str, int pos1, int pos2){

char t1 = str.charAt(pos1);

str.setCharAt(pos1, str.charAt(pos2));

str.setCharAt(pos2, t1);

}

}