Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
6th Edition
ISBN: 9780134477367
Author: David J. Barnes, Michael Kolling
Publisher: PEARSON
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Chapter 1, Problem 25E
Look at the signature of the enrollStudent method. You will notice that the type of the expected parameter is Student. Make sure you have two or three students and a LabClass object on the object bench, then call the enrollStudent method of the LabClass object. With the input cursor in the dialog entry field, click on one of the student objects; this enters the name of the student object into the parameter field of the enroll Student method (Figure 1.9). Click OK and you have added the student to the LabCl ass. Add one or more other students as well.
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In this exercise, you are going to build on your Circleclass from the previous exercise.
You are going to add 2 method, areaDifference and perimeterDifference. Both methods take a doubleradius of a second circle and return the difference from the current circle.
For example, if you create a Circle object with a radius of 4 and call areaDifference(3), you will return the diffence between the area of a circle with radius 4 and the area of a circle with a radius of 3. perimeterDifferencewould be the same.
Make sure you create at least one Circle and test and print the results of your methods.
in java
In this exercise, you are going to build on your Circleclass from the previous exercise.
You are going to add 2 method, areaDifference and perimeterDifference. Both methods take a doubleradius of a second circle and return the difference from the current circle.
For example, if you create a Circle object with a radius of 4 and call areaDifference(3), you will return the diffence between the area of a circle with radius 4 and the area of a circle with a radius of 3. perimeterDifferencewould be the same.
Make sure you create at least one Circle and test and print the results of your methods.
given: public class Circle{private double radius;public Circle(double theRadius){radius = theRadius;}// Add a method called area that returns the area of a circle// using Math.PIpublic double area(){return Math.PI*radius*radius;}// Add a method called perimeter that returns the perimeter of a// circle using Math.PIpublic double perimeter(){return Math.PI*2*radius;}}
For this exercise, you are given a Team superclass with a BaseballTeam and FootballTeam subclass. Take a moment to examine these classes and the instance variables and methods in each.
In the TeamTester class, you will see three objects declared and instantiated using the Team, FootballTeam, or BaseballTeam classes.
For each object, use a print statement to print out any public method that returns information that is available for that particular object, including the toString.
For example, the dolphin object is a FootballTeam object. One of the pieces of information that can be printed is the getTies() method, so you will call that method in your TeamTester file:
System.out.println(dolphins.getTies());
Do this for all the methods that each of the objects can call.
Hint: Remember, for the program to compile and run, Java looks for methods to exist in certain classes.
=================================
public class Team {
private String name;private String location;private int…
Chapter 1 Solutions
Objects First with Java: A Practical Introduction Using BlueJ (6th Edition)
Ch. 1 - Prob. 1ECh. 1 - Prob. 2ECh. 1 - Prob. 3ECh. 1 - Prob. 4ECh. 1 - This is a very simple example, and not many colors...Ch. 1 - Prob. 6ECh. 1 - Prob. 7ECh. 1 - Prob. 8ECh. 1 - Prob. 9ECh. 1 - Select Show Terminal from the View menu. This...
Ch. 1 - Select Show Code Pad from the View menu. This...Ch. 1 - Prob. 12ECh. 1 - Prob. 13ECh. 1 - Prob. 14ECh. 1 - Look at the pop-up menu of class Picture again....Ch. 1 - In the source code of class Picture, find the part...Ch. 1 - Add a second sun to the picture. To do this, pay...Ch. 1 - Prob. 18ECh. 1 - Prob. 19ECh. 1 - Prob. 20ECh. 1 - Create an object of class Student. You will notice...Ch. 1 - Prob. 22ECh. 1 - Prob. 23ECh. 1 - Call the numberOfStudents method of that class....Ch. 1 - Look at the signature of the enrollStudent method....Ch. 1 - Prob. 26ECh. 1 - Prob. 27ECh. 1 - Prob. 28ECh. 1 - Prob. 29ECh. 1 - In this chapter we have mentioned the data types...Ch. 1 - What are the types of the following values?...Ch. 1 - Prob. 32ECh. 1 - Write the header for a method named send that has...Ch. 1 - Prob. 34ECh. 1 - Prob. 35ECh. 1 - Prob. 36E
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