public class MyClass
{
public static String reverse(String str) {
int len = str.length();
char[] arr = new char[len];
for (int i = 0; i < len; i++) {
arr[len - i - 1] = str.charAt(i);
}
return String.copyValueOf(arr);
}
public static void main(String[] args)
{
String str = "java9";
str = reverse(str);
System.out.println(str);
}
}
/*
run:
9avaj
*/