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Figure 1 - Question 1.
class java.awt.Button Button01class java.awt.Button Button02class java.awt.Label Label01class java.awt.Label Label02

Answer 1

Question 2

True or False: The code shown in Listing 2 will compile and run successfully producing the output shown in Figure 2 .

Listing 2 - Question 2.

/*File Q02.java ************************************************/import java.util.ArrayList; import java.awt.Button;import java.awt.Label; import java.awt.Component;public class Q02{ /*Given: Button and Label are subclasses of the Componentclass. The getClass method is defined in the Objectclass. When called on a reference to an object, the method returns the name of the class fromwhich the object was instantiated. */public static void main(String[] args){//Create and populate a list designed to // store references to objects of type Button// and display its contents. ArrayList<Button>listA = new ArrayList<>(); listA.add(new Button("Button01"));listA.add(new Button("Button02")); display(listA);System.out.println("");//blank line //Create and populate a list designed to// store references to objects of type Label // and display its contents.ArrayList<Label>listB = new ArrayList<>(); listB.add(new Label("Label01"));listB.add(new Label("Label02")); display(listB);}//end main //-------------------------------------------//static void display( ArrayList<? extends Component>list){ for(Component n : list){System.out.println(n.getClass()); if(n instanceof Button){System.out.println( ((Button)n).getLabel());}else if(n instanceof Label) { System.out.println(((Label)n).getText());}//end else }//end for loop}//end display }//end class Q02
Figure 2 - Question 2.
class java.awt.Button Button01class java.awt.Button Button02class java.awt.Label Label01class java.awt.Label Label02

Answer 2

Question 3

True or False: The code shown in Listing 3 will compile and run successfully producing the output shown in Figure 3 .

Listing 3 - Question 3.

/*File Q03.java ************************************************/import java.util.ArrayList; import java.awt.Button;import java.awt.Label; import java.awt.Component;public class Q03{ /*Given: Button and Label are subclasses of the Componentclass. The getClass method is defined in the Objectclass. When called on a reference to an object, the method returns the name of the class fromwhich the object was instantiated. */public static void main(String[] args){//Create and populate a list designed to // store references to objects of type Button// and display its contents. ArrayList<Button>listA = new ArrayList<>(); listA.add(new Button("Button01"));listA.add(new Button("Button02")); display(listA);System.out.println("");//blank line //Create and populate a list designed to// store references to objects of type Label // and display its contents.ArrayList<Label>listB = new ArrayList<>(); listB.add(new Label("Label01"));listB.add(new Label("Label02")); display(listB);}//end main //-------------------------------------------//static void display(ArrayList<?>list){ for(Object n : list){System.out.println(n.getClass()); if(n instanceof Button){System.out.println( ((Button)n).getLabel());}else if(n instanceof Label) { System.out.println(((Label)n).getText());}//end else }//end for loop}//end display }//end class Q03

Questions & Answers

what is math number
Tric Reply
x-2y+3z=-3 2x-y+z=7 -x+3y-z=6
Sidiki Reply
Need help solving this problem (2/7)^-2
Simone Reply
x+2y-z=7
Sidiki
what is the coefficient of -4×
Mehri Reply
-1
Shedrak
the operation * is x * y =x + y/ 1+(x × y) show if the operation is commutative if x × y is not equal to -1
Alfred Reply
An investment account was opened with an initial deposit of $9,600 and earns 7.4% interest, compounded continuously. How much will the account be worth after 15 years?
Kala Reply
lim x to infinity e^1-e^-1/log(1+x)
given eccentricity and a point find the equiation
Moses Reply
12, 17, 22.... 25th term
Alexandra Reply
12, 17, 22.... 25th term
Akash
College algebra is really hard?
Shirleen Reply
Absolutely, for me. My problems with math started in First grade...involving a nun Sister Anastasia, bad vision, talking & getting expelled from Catholic school. When it comes to math I just can't focus and all I can hear is our family silverware banging and clanging on the pink Formica table.
Carole
I'm 13 and I understand it great
AJ
I am 1 year old but I can do it! 1+1=2 proof very hard for me though.
Atone
hi
Adu
Not really they are just easy concepts which can be understood if you have great basics. I am 14 I understood them easily.
Vedant
hi vedant can u help me with some assignments
Solomon
find the 15th term of the geometric sequince whose first is 18 and last term of 387
Jerwin Reply
I know this work
salma
The given of f(x=x-2. then what is the value of this f(3) 5f(x+1)
virgelyn Reply
hmm well what is the answer
Abhi
If f(x) = x-2 then, f(3) when 5f(x+1) 5((3-2)+1) 5(1+1) 5(2) 10
Augustine
how do they get the third part x = (32)5/4
kinnecy Reply
make 5/4 into a mixed number, make that a decimal, and then multiply 32 by the decimal 5/4 turns out to be
AJ
how
Sheref
can someone help me with some logarithmic and exponential equations.
Jeffrey Reply
sure. what is your question?
ninjadapaul
20/(×-6^2)
Salomon
okay, so you have 6 raised to the power of 2. what is that part of your answer
ninjadapaul
I don't understand what the A with approx sign and the boxed x mean
ninjadapaul
it think it's written 20/(X-6)^2 so it's 20 divided by X-6 squared
Salomon
I'm not sure why it wrote it the other way
Salomon
I got X =-6
Salomon
ok. so take the square root of both sides, now you have plus or minus the square root of 20= x-6
ninjadapaul
oops. ignore that.
ninjadapaul
so you not have an equal sign anywhere in the original equation?
ninjadapaul
hmm
Abhi
is it a question of log
Abhi
🤔.
Abhi
I rally confuse this number And equations too I need exactly help
salma
But this is not salma it's Faiza live in lousvile Ky I garbage this so I am going collage with JCTC that the of the collage thank you my friends
salma
Commplementary angles
Idrissa Reply
hello
Sherica
im all ears I need to learn
Sherica
right! what he said ⤴⤴⤴
Tamia
hii
Uday
hi
salma
hi
Ayuba
Hello
opoku
hi
Ali
greetings from Iran
Ali
salut. from Algeria
Bach
hi
Nharnhar
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Source:  OpenStax, Object-oriented programming (oop) with java. OpenStax CNX. Jun 29, 2016 Download for free at https://legacy.cnx.org/content/col11441/1.201
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