Description
1. a) Modify the following program to become a generic class called StorePairGeneric.
public class StorePair {
private int first, second;
public StorePair(int first, int second) {
this.first = first;
this.second = second;
}
public int getFirst() {
return first;
}
public int getSecond() {
return second;
}
public void setPair(int first, int second) {
this.first = first;
this.second = second;
}
public String toString() {
return “first = ” + first + ” second = ” + second;
}
}
b) Override the Object equals() method in the StorePair class to compare the first
values of two objects for equality.
c) Have the StorePair class implement the Comparable interface. Override the
compareTo()method to compare the first values of two objects.
d) Create a test program that creates three objects of the StorePairgeneric class called
a, b and c. Set the first and second values of a, b, c as (6,4), (2,2), (6,3).
e) Invoke the compareTo()and equals() methods that compares the three objects
created in (d) in the test program.
WIA1002/WIB1002
Page 2
2. Create a generic class called MyGeneric that accepts one parameter. Declare a variable
called e for the type parameter. Create a no-arg constructor. Create a constructor that
accepts one generic parameter. Create a setter and getter method for the generic type.
Create a test program that creates two instances of generic class of type String called
strObj and of type Integer called intObj. Set a value for each of these objects. Display
these values using the getter method.
3. In a class called CompareMax, create a generic static method called maximum where the
generic type extends the Comparable interface, which receives three parameters. Find
the maximum of three values invoked by the main method.
4. Provide a declaration and implementation of the generic method minmax() that takes
in an array of generic type and returns a string with the following format: Min =
Max = . For instance, in your main method, create one object of type array
for integers and one object of type string:
Integer[] intArray = {5,3,7,1,4,9,8,2};
String[] strArray = {“red”, “blue”, “orange”, “tan”};
minmax() method returns “Min = 1 Max = 9” For intArray
minmax() method returns “Min = blue Max = tan” for strArray
*Hint: use Comparable interface to compare the values
*Hint: compareTo() method:
if a > b, it returns positive number
if a < b, it returns negative number
if a == b, it returns 0
5. Create a class called FindMax that contains the following:
Create a Circle class that uses the Comparable interface. Declare the radius
variable and a single parameterized constructor that accepts this variable.
In your main program, create 3 different objects of type array (a) for integers that stores
the following values, 1,2,3; (b) a list of string that stores red, green, blue and (c) a circle
object of radius 3, 2.9 and 5.9. Invoke the max method as below:
public static > E max(E[] list)
The max method above returns the maximum value in an array.
WIA1002/WIB1002 Lab 4
Page 3
6. In a class called MinMaxTwoDArray, write two generic methods:
a. First method returns the minimum element in a two-dimensional array. Below is the
method signature:
public static > E min(E[][] list)
b. Second method returns the maximum element in a two-dimensional array. Below is
the method signature:
public static > E max(E[][] list)
c. Create a test program that creates one instance of generic class of type Integer called
numbers with the elements: {4, 5, 6}, {1, 2, 3}. Display the minimum and maximum
elements using the min and max methods.
