Week-1

Exercise 1.b, page 21:

I needed to see which of the 3 part of code have errors... (i should be a compiler...)

A: Goes to a endless loop (missing and x=x+1)

B: Missing the start of the program, "class Excercise 1b{}"

C: Missing psvm

Exercise 2.a, page 42:

See if the files will compile, how to fix and what is their output...

A: Missing "TapeDeck t = new TapeDeck", output: "tape playing" //ln// "tape recording"

B: Missing method "playDVD" (can just remove line d.playDVD;), output: "DVD recording"

Exercise 3.a, page 63:

See if the files will compile, how to fix and what is their output...

A: Missing the creation of new books for every book in the array! (Books myBooks[x]=new Books())

B: It's trying to create a object that's not in the bounderies of the array (array[3] -> 0-2, gona make object 3)

Exercise 4.a, page 88:

See if the files will compile, how to fix and what is their output...

A: Everything is ok here (i couldn't find and error with is the solution)

B: public/private? -> the problem was that getters need to have a defined type (i didn't manage to notice that... :S)

Exercise 4.b, page 89:

"who am i?" -> 13 statements and i have to assign 10 stuff to those statements...

Instance variable, argument, return, getter, setter, encapsulation, public, private, pass by value, method

1. "A class can have any number of these." -> instance variable, getter, setter, method
2. "A method can have only one of these." -> return
3. "this can be implicitly promoted." -> ??? (argument, return, they can be a smaller type then the output type)
4. "I prefer my instance variables private." -> encapsulation
5. "It really means "make a copy" -> pass by value
6. "Only setters should update these" -> prvate (correct is instance variable :S)
7. "A method can have many of these." -> argument~~, instance variable~~ (correct is only argument :O)
8. "I return something by definition" -> ~~return (method, ~~getter) / correct is getter
9. "I shouldn't be used with instance variables." -> public
10. "I can have many arguments." -> method
11. "By definition, I take one argument." -> setter
12. "These help create encapsulation." -> getter, setter, public, private
13. "I always fly solo." -> return

Excercise 7.a, page 192:

i have to connect 4 blocks of code to the right output (7 outputs, not all are correct and not all codes are correct)

(answers are a little jumbled in the book -> for the 3rd and 4th code blocks)

1. the first code will print the "B m1", "A m2", "A m3" -> 2nd output
2. the 2nd code will print "B m1", "A m2", "C m3", 13 -> 4th output
3. the 3rd code will print "A m1", "A m2", "C m3", 13 -> 7th output
4. the 4th code will print "B m1", "A m2", "C m3", 13 -> 4th output

Exercise 7.b, page 193:

4 check if the code will work... which will work and produce selected output?

1. True
2. False -> return type is wrong
3. False -> doesn't override the frighten method
4. False -> parametar is a byte isntead of int