In java,

Open the String class in the Java API, and take a look at the different versions of the indexOf() and substring() methods, identify what parameters each version of those methods accept and what does it return, and do the following: Create a class named MiniString, the class should have the following: - A private String instance variable named str. - A constructor that takes a String as a parameter and sets the instance variable str to the parameter String. - Create 2 methods each named makeSubstring(), and each version of makeSubstring() will implement a version of the substring() method from the Java API String class. - Create 4 methods each named findIndexOf(), and each version of findIndexOf() will implement a version of the indexOf() method from the Java API String class. - The only 3 String methods you can use to solve this problem are: charAt(), length() and equals(). - IF YOU use any other method from the String class, you will not get credit for this problem. - In this problem, you are actually re-inventing the wheel. You are implementing methods that already exist in the Java API. its really important to know how those methods work, and how to build them from scratch.