15.12. NumberGroup - Part B¶

Part b. A range represents a number group that contains all (and only) the integers between a minimum value and a maximum value, inclusive. Write the Range class, which is a NumberGroup. The Range class represents the group of int values that range from a given minimum value up through a given maximum value, inclusive. For example, the declaration NumberGroup range1 = new Range(-3, 2); represents the group of integer values -3, -2, -1, 0, 1, 2.

Write the complete Range class. Include all necessary instance variables and methods as well as a constructor that takes two int parameters. The first parameter represents the minimum value, and the second parameter represents the maximum value of the range. You may assume that the minimum is less than or equal to the maximum. Write the contains method which returns true or false if a given int argument is within the range set up by the constructor.

15.12.1. Try and Solve It¶

Complete the class Range below with instance variables, a constructor, and a contains method.

class NumberGroup
{
    /* Implementation not shown */
}

public class Range extends NumberGroup
{
    // Write the instance variables for the Range class here

// Write the Range constructor with 2 parameters
    // for the minimum and maximum values in the range

// Write the contains method which tests whether a
    // given number is in the range.

// Main method to test the class
    public static void main(String[] args)
    {
        System.out.println("This is testing the constructor");
        Range test = new Range(5, 8);
        // Test the contains method
        System.out.println(
                "Does the range contain 4 (should be false): " + test.contains(4));
        System.out.println(
                "Does the range contain 5 (should be true): " + test.contains(5));
    } // end of main
} // end of class

====
import static org.junit.Assert.*;

import org.junit.*;

import java.io.*;

// import java.util.ArrayList;

public class RunestoneTests extends CodeTestHelper
{
    public RunestoneTests()
    {
        super("Range");
        // CodeTestHelper.sort = true;
    }

@Test
    public void testMain1()
    {
        boolean passed = false;

String expect =
                "This is testing the constructor\n"
                    + "Does the range contain 4 (should be false): false\n"
                    + "Does the range contain 5 (should be true): true";

String output = getMethodOutput("main");

passed = getResults(expect, output, "Checking for expected output from main");
        assertTrue(passed);
    }

@Test
    public void testMain2()
    {
        boolean passed = false;

Range test = new Range(5, 80);
        // Test the contains method
        String expect = "false";
        String output = "" + test.contains(0);

passed = getResults(expect, output, "Checking that Range(5, 80) contains(0)");
        assertTrue(passed);
    }

@Test
    public void testMain3()
    {
        boolean passed = false;

Range test = new Range(5, 80);
        // Test the contains method
        String expect = "true";
        String output = "" + test.contains(10);

passed = getResults(expect, output, "Checking that Range(5, 80) contains(10)");
        assertTrue(passed);
    }
}

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