lab03

What do you think is the type of each of the following fields?

• private int count - int
• private Student representative - Student
• private Server host - Server

What are the names of the following fields?

• private boolean alive - alive
• private Person tutor - tutor
• private Game game - game

From what you know about the naming conventions for classes, which of the type names in the above questions would you say are class names?

• The naming conventions for classes starts with a capital letter. The type names in the above questions that are class names are Student, Server, Person and Game.

In the following field declaration from the TicketMachine class

private int price;

does it matter which order the three words appear in? 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? Check by pressing the Compile button to see if there is an error message. Make sure that you reinstate the original version after your experiments! -You can't change the order of "private int price".

Is it always necessary to have a semicolon at the end of a field declaration? Once again, experiment via the editor. The rule you will learn here is an important one, so be sure to remember it.

• Yes, it is always necessary to have a semicolon at the end of a field declaration or else there is no end to whatever you are defining.

Write in full the declaration for a field of type int whose name is status.

• private int status;

To what class does the following constructor belong?

public Student(String name)

• The constructor belongs to class Student.

How many parameters does the following constructor have, and what are their types?

public Book(String title, double price)

• The constructor have 2 parameters and their types are string and double.

Can you guess what types some of the Book class’s fields might be, from the parameters in its constructor? Can you assume anything about the names of its fields?

• Some of the 'Book' class's fields from the parameters in its constructor might be strings and doubles. For the most part, names will be similar to parameters.

Suppose that the class Pet has a field called name that is of the type String. Write an assignment statement in the body of the following constructor so that the name field will be initialized with the value of the constructor’s parameter.

public Pet(String petsName)
{
}

public Pet(String petsName) { name = petsName; }

The following object creation will result in the constructor of the Date class being called. Can you write the constructor’s header?

new Date("March", 23, 1861)

• public class Date(String month, int date, int year)

Try to give meaningful names to the parameters.