java string reverse

public class ReverseString {
    public static void main(String[] args) {
        String s1 = "neelendra";
        for(int i=s1.length()-1;i>=0;i--)
            {
                System.out.print(s1.charAt(i));
            }
    }
}String str = "Hello";
String reverse(String str){
  StringBuilder sb = new StringBuilder();
  sb.append(str);
  sb.reverse();
  return sb.toString();
}String str = "Reverse this strings";
//for loop
for (int i = str.length() - 1; i >= 0; i--) {
	System.out.print(str.charAt(i));
}

// StringBuffer for multi thread
StringBuffer sb = new StringBuffer(); 
sb.append(str);
System.out.print(sb.reverse().toString());

// StringBuffer for single thread
StringBuilder sb = new StringBuilder(); 
sb.append(str);
System.out.print(sb.reverse().toString());