From cdbe6cb4b322038176a75b825762864a6a9ada11 Mon Sep 17 00:00:00 2001 From: Jessicahe29 <85531207+Jessicahe29@users.noreply.github.com> Date: Thu, 24 Jun 2021 20:07:44 -0400 Subject: [PATCH] Update README.md --- README.md | 55 ++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 36 insertions(+), 19 deletions(-) diff --git a/README.md b/README.md index ee11f2c..4a74b9f 100644 --- a/README.md +++ b/README.md @@ -22,12 +22,15 @@ Work through all these exercises. You edit this file with your answers for these ### Exercise 2.2 * What value is returned if you check the machine’s balance after it has printed a ticket? - +- The value is 0. ### Exercise 2.3 * Experiment with inserting different amounts of money before printing tickets. - * Do you notice anything strange about the machine’s behavior? + * Do you notice anything strange about the machine’s behavior? + - The refund and balance stays at 0 even with different prices. * What happens if you insert too much money into the machine – do you receive any refund? + - There is no refund. * What happens if you do not insert enough and then try to print a ticket? + - The ticket still prints regardless of the price. ### Exercise 2.4 * Try to obtain a good understanding of a ticket machine’s behavior by interacting with it on the object bench before we start looking at how the `TicketMachine` class is implemented in the next section. @@ -36,9 +39,13 @@ Work through all these exercises. You edit this file with your answers for these * Create another ticket machine for tickets of a different price. * Buy a ticket from that machine. * Does the printed ticket look different? - + - There is no difference. ### Exercise 2.6 * Write out what you think the outer wrappers of the `Student` and `LabClass` classes might look like – do not worry about the inner part. +public class Student { +} +public class LabClass { +} ### Exercise 2.7 Does it matter whether we write
@@ -46,39 +53,46 @@ Does it matter whether we write
or
`class public TicketMachine`
in the outer wrapper of a class? - +- Yes, it must be written properly. * Edit the source of the `TicketMachine` class to make the change and then close the editor window. * Do you notice a change in the class diagram? + - Yes, there are red marks on the 'TicketMachine' class. * What error message do you get when you now press the compile button? + - It states error found in class. * Do you think this message clearly explains what is wrong? - + - Yes, it marks the line of code that needs to be fixed in red in order to be complied. + ### Exercise 2.8 * Check whether or not it is possible to leave out the word `public` from the outer wrapper of the `TicketMachine` class. - +- Yes, there are no errors. ### Exercise 2.9 * From your earlier experimentation with the ticket machine objects within BlueJ you can probably remember the names of some of the methods – `printTicket`, for instance. * Look at the class definition in Code 2.1 and use this knowledge, along with the additional information about ordering we have given you, to try to make a list of the names of the fields, constructors, and methods in the `TicketMachine` class. * Hint: There is only one constructor in the class. + Methods- printTicket, insertMoney, getTicketNumber, getPrice + Fields- ticketNumber, total, balance, price + Constructor- TicketMachine + ### Exercise 2.10 * Do you notice any features of the constructor that make it significantly different from the other methods of the class? - +- The features of the constructor is different because it is the same as the class. ### Exercise 2.11 * What do you think is the type of each of the following fields? ```java -private int count; -private Student representative; -private Server host; +private int count; int +private Student representative; Student +private Server host; Server ``` ### Exercise 2.12 * What are the names of the following fields? ```java -private boolean alive; -private Person tutor; -private Game game; +private boolean alive; alive +private Person tutor; tutor +private Game game; game ``` ### Exercise 2.13 @@ -88,35 +102,38 @@ In the following field declaration from the TicketMachine class
private int price; ``` does it matter which order the three words appear in? +- Yes, it matters. * Edit the `TicketMachine` class to try different orderings. After each change, close the editor. - * Does the appearance of the class diagram after each change give you a clue as to whether or not other orderings are -possible? + * Does the appearance of the class diagram after each change give you a clue as to whether or not other orderings are possible? + - Yes there are error marks not allowing the order to change. * Check by pressing the compile button to see if there is an error message. * Make sure that you reinstantiate the original version after your experiments! ### Exercise 2.14 * Is it always necessary to have a semicolon at the end of a field declaration? +- It is always necessary to have a semicolon. * Once again, experiment via the editor. * The rule you will learn here is an important one, so be sure to remember it. ### Exercise 2.15 * Write in full the declaration for a field of type `int` whose name is `status`. - +public int status; ### Exercise 2.16 * To what class does the following constructor belong? ``` public Student(String name) ``` - +- The class it belongs to is Student. ### Exercise 2.17 * How many parameters does the following constructor have and what are their types? ``` public Book(String title, double price) ``` - + - There are 2 parameters in the constructor and the types are String and double. ### Exercise 2.18 -* Can you guess what types some of the `Book` class’s fields might be? +* Can you guess what types some of the `Book` class’s fields might be? +- The 'Book' class's type might be Sting and double. * Can you assume anything about the names of its fields? READ upto and INCLUDING section 2.15 of this chapter.