Java에서 StringBuilder를 사용하여 문자열을 뒤집는 방법

package net.javaguides.corejava.string;
/**
* 
* @author yisu
*
*/
public class ReverseWithStringBuilderBuiltinMethod {
public static void main(String[] args) {
ReverseWithStringBuilderBuiltinMethod builtinMethod = new ReverseWithStringBuilderBuiltinMethod();
builtinMethod.reverseWithStringBuilderBuiltinMethod("javaguides");
}
public String reverseWithStringBuilderBuiltinMethod(String string) {
final StringBuilder builder = new StringBuilder(string);
display(string, builder.reverse().toString());
return builder.reverse().toString();
}
private void display(String input, String output) {
System.out.println(" input string :: " + input);
System.out.println(" output string :: " + output);
}
}

input string :: javaguides
output string :: sediugavaj