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62 changes: 39 additions & 23 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -18,48 +18,58 @@ Work through all these exercises. You edit this file with your answers for these
* Use `getPrice` method to view the value of the price of the tickets that was set when this object was created.
* Use `insertMoney` method to simulate inserting an amount of money into the machine.
* Use `getBalance` to check that the machine has a record of the amount inserted.
* You can insert several separate amounts of money into the machine, just like you might insert multiple coins or notes into a real machine. Try inserting the exact amount required for a ticket. As this is a simple machine, a ticket will not be issued automatically, so once you have inserted enough money, call the `printTicket` method. A facsimile ticket should be printed in the BlueJ terminal window.
* You can insert several separate amounts of money into the machine, just like you might insert multiple coins or notes into a real machine. Try inserting the exact amount required for a ticket. As this is a simple machine, a ticket will not be issued automatically, so once you have inserted enough money, call the `printTicket` method. A facsimile ticket should be printed in the BlueJ terminal window.

### Exercise 2.2
* What value is returned if you check the machine’s balance after it has printed a ticket?

I got the value 0
### Exercise 2.3
* Experiment with inserting different amounts of money before printing tickets.
* Do you notice anything strange about the machine’s behavior?
* What happens if you insert too much money into the machine – do you receive any refund?
* What happens if you do not insert enough and then try to print a ticket?
* Do you notice anything strange about the machine’s behavior?
* What happens if you insert too much money into the machine – do you receive any refund?
* What happens if you do not insert enough and then try to print a ticket?
- it still was the same no matter how much I put in

### 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.

### Exercise 2.5
* Create another ticket machine for tickets of a different price.
* Buy a ticket from that machine.
* Does the printed ticket look different?
* Buy a ticket from that machine.
* Does the printed ticket look different?
* no it did not

### 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<br>
`public class TicketMachine`<br>
or<br>
`class public TicketMachine`<br>
in the outer wrapper of a class?

it gave me an error
* 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?
* What error message do you get when you now press the compile button?
* Do you think this message clearly explains what is wrong?

* Do you notice a change in the class diagram?
* What error message do you get when you now press the compile button?
* Do you think this message clearly explains what is wrong?
it showed me red slashes
illegal expression
no
### Exercise 2.8
* Check whether or not it is possible to leave out the word `public` from the outer wrapper of the `TicketMachine` class.

no syntax error
### 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.

* 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.
integer would be fields, constructor would be the public ticket machine, methods would be get balance and get price
### Exercise 2.10
* Do you notice any features of the constructor that make it significantly different from the other methods of the class?

Expand All @@ -71,6 +81,7 @@ private int count;
private Student representative;
private Server host;
```
int, student, server

### Exercise 2.12
* What are the names of the following fields?
Expand All @@ -80,6 +91,8 @@ private boolean alive;
private Person tutor;
private Game game;
```
alive, tutor, game

### Exercise 2.13

In the following field declaration from the TicketMachine class<br>
Expand All @@ -88,35 +101,38 @@ In the following field declaration from the TicketMachine class<br>
private int price;
```
does it matter which order the three words appear in?
yes it does
* 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
* 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 reinstantiate the original version after your experiments!
* 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?
yes
* 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`.

int status
### Exercise 2.16
* To what class does the following constructor belong?
```
public Student(String name)
```

Student
### Exercise 2.17
* How many parameters does the following constructor have and what are their types?
```
public Book(String title, double price)
```

2
### Exercise 2.18
* Can you guess what types some of the `Book` class’s fields might be?
int
* Can you assume anything about the names of its fields?

yes
READ upto and INCLUDING section 2.15 of this chapter.
2 changes: 1 addition & 1 deletion TicketMachineTest.java
Original file line number Diff line number Diff line change
Expand Up @@ -11,7 +11,7 @@
* @author (your name)
* @version (a version number or a date)
*/
public class TicketMachineTest
class TicketMachineTest
{
/**
* Default constructor for test class TicketMachineTest
Expand Down
54 changes: 35 additions & 19 deletions bluej.pkg
Original file line number Diff line number Diff line change
@@ -1,32 +1,48 @@
#BlueJ package file
editor.fx.0.height=722
editor.fx.0.width=800
editor.fx.0.x=709
editor.fx.0.y=113
dependency1.from=TicketMachineTest
dependency1.to=TicketMachine
dependency1.type=UsesDependency
editor.fx.0.height=804
editor.fx.0.width=969
editor.fx.0.x=541
editor.fx.0.y=123
objectbench.height=101
objectbench.width=461
package.divider.horizontal=0.6
objectbench.width=665
package.divider.horizontal=0.8615384615384616
package.divider.vertical=0.8007380073800738
package.editor.height=427
package.editor.width=674
package.editor.x=1067
package.editor.y=119
package.editor.width=682
package.editor.x=952
package.editor.y=134
package.frame.height=600
package.frame.width=800
package.numDependencies=0
package.numTargets=1
package.numDependencies=1
package.numTargets=3
package.showExtends=true
package.showUses=true
project.charset=UTF-8
readme.height=58
readme.height=60
readme.name=@README
readme.width=47
readme.width=48
readme.x=10
readme.y=10
target1.height=50
target1.name=TicketMachine
target1.height=70
target1.name=TicketMachineTest
target1.showInterface=false
target1.type=ClassTarget
target1.width=120
target1.x=80
target1.y=50
target1.type=UnitTestTargetJunit4
target1.width=130
target1.x=140
target1.y=120
target2.height=50
target2.name=TicketMachine
target2.showInterface=false
target2.type=ClassTarget
target2.width=120
target2.x=80
target2.y=50
target3.height=70
target3.name=README.md
target3.type=TextTarget
target3.width=120
target3.x=10
target3.y=110
54 changes: 35 additions & 19 deletions package.bluej
Original file line number Diff line number Diff line change
@@ -1,32 +1,48 @@
#BlueJ package file
editor.fx.0.height=722
editor.fx.0.width=800
editor.fx.0.x=709
editor.fx.0.y=113
dependency1.from=TicketMachineTest
dependency1.to=TicketMachine
dependency1.type=UsesDependency
editor.fx.0.height=804
editor.fx.0.width=969
editor.fx.0.x=541
editor.fx.0.y=123
objectbench.height=101
objectbench.width=461
package.divider.horizontal=0.6
objectbench.width=665
package.divider.horizontal=0.8615384615384616
package.divider.vertical=0.8007380073800738
package.editor.height=427
package.editor.width=674
package.editor.x=1067
package.editor.y=119
package.editor.width=682
package.editor.x=952
package.editor.y=134
package.frame.height=600
package.frame.width=800
package.numDependencies=0
package.numTargets=1
package.numDependencies=1
package.numTargets=3
package.showExtends=true
package.showUses=true
project.charset=UTF-8
readme.height=58
readme.height=60
readme.name=@README
readme.width=47
readme.width=48
readme.x=10
readme.y=10
target1.height=50
target1.name=TicketMachine
target1.height=70
target1.name=TicketMachineTest
target1.showInterface=false
target1.type=ClassTarget
target1.width=120
target1.x=80
target1.y=50
target1.type=UnitTestTargetJunit4
target1.width=130
target1.x=140
target1.y=120
target2.height=50
target2.name=TicketMachine
target2.showInterface=false
target2.type=ClassTarget
target2.width=120
target2.x=80
target2.y=50
target3.height=70
target3.name=README.md
target3.type=TextTarget
target3.width=120
target3.x=10
target3.y=110