in Java Part B: Strategy PatternWe've already seen a design pattern, the iterator pattern, that allowed us to iterate over any collection ofitems without knowing how the collection is actually implemented. In this part of the lab, we'll be looking atanother design pattern called the Strategy Pattern. It involves applying a collection of methods (with aninterface in common) to a list of objects.Create an interface like this:public interface OpClass {abstract Object op (Object arg);Next, create three classes Square, Cube, and SquareRoot that implement this interface. The Squareshould convert the arg to a Number, square it, then return the Number as an object. The Cube will do thesame thing, expect it will cube the number. The same applies to the SquareRoot which returns the squareroot of the number.Create a method called apply in another public class called Calculator and implement your main methodhere. The apply method should accept an ArrayList of Numbers and an OpClass to apply to the list. Itshould return a new ArrayList with the new values in it. Make use of the ArrayList iterator here as well.Test this out by building a list of integers, and applying the square, cube, then square root objects on thelist. Print out the list after each application. Part A: Constructor DerivationCreate the following:<BaseооConstructor prints "Base constructor."Has two methods called:<"m1 that increments the number of times m1 is called, then prints that value.m2(String s) that prints the given string with "from Base"оITypeо"A static integer that counts the number of times m1 is called.An interface with methods for:"m2(String s)m3()Derived extends Base implements ITypeо Constructor prints "Derived Constructor"оMethods:m1() that prints "Derived.m1""m3() that prints "Derived.m3"Derived2 extends DerivedооConstructor prints "Derived2 Constructor"Methods:■m2(String s) that prints the given string with "from Derived2"m4() that prints "Derived2.m4"➤ Separate implements ITypeо Constructor prints "Separate Contructor"о Implement methods for the following and have them do the same as the methods above:m1m2(String s)m3Note how the interface implementation in IType is satisfied with the m2 method definition in Base when itis implemented in Derived. Now initialize a Base, Derived, and then Derived2 and observe theinitialization sequence in the terminal. You should see Base (or superclass) constructors being calledbefore subclass constructors.Call all methods on the objects to see what they do and call m1 in the Base class twice. Lastly, create anArrayList of Base objects and fill it with an assortment of 10 Base, Derived, and Derived2 objects. Iterateover this list and call the m2 method on all objects.

Part b AlgorithmCreated an interfaceOpClass.Created three classes Square, Cube, and…

Part B: Strategy Pattern We've already seen a design pattern, the iterator pattern, that allowed us to iterate over any collection of items without knowing how the collection is actually implemented. In this part of the lab, we'll be looking at another design pattern called the Strategy Pattern. It involves applying a collection of methods (with an interface in common) to a list of objects. Create an interface like this: public interface OpClass { abstract Object op (Object arg); Next, create three classes Square, Cube, and SquareRoot that implement this interface. The Square should convert the arg to a Number, square it, then return the Number as an object. The Cube will do the same thing, expect it will cube the number. The same applies to the SquareRoot which returns the square root of the number. Create a method called apply in another public class called Calculator and implement your main method here. The apply method should accept an ArrayList of Numbers and an OpClass to apply to the list. It should return a new ArrayList with the new values in it. Make use of the ArrayList iterator here as well. Test this out by building a list of integers, and applying the square, cube, then square root objects on the list. Print out the list after each application.

9th Edition

ISBN:9781337671385

Author:FARRELL

Publisher:FARRELL

Chapter4: More Object Concepts

Section: Chapter Questions

Problem 10RQ