Implement the your own StringBuilder class that does not extends from The StringBuilder class is provided in the Java library.

( your class name will be "text): Add the following methods to make your own changes on your text: public text (String s); public text append(text s); public text append(int i); public int length(); public char charAt(int index); public text toLowerCase(); public text substring(int begin, int end); public String toString()

and write a test program