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Listing 5 - Question 5.
/*File Q05.java ************************************************//* Integer and Double are both subclasses ofNumber. Both classes define a method named doubleValue that returns the encapsulatednumeric value as type double. Both classes also contain a method named intValue thatreturns the encapsulated numeric value as type int.*/ public class Q05{public static void main(String[] args){Foo<Integer>iFoo = new Foo<Integer>(15); System.out.println(iFoo.get().intValue());displayClass(iFoo); }//end main//-------------------------------------------// static void displayClass(Foo<Number>obj){ System.out.println(obj.getClass());}//end displayClass }//end class Q05//=============================================// class Foo<T extends Number>{ private T obj;public Foo(T obj){ this.obj = obj;}//end constructor public T get(){return obj; }//end get}//end Foo //=============================================//
Figure 5 - Question 5.
15 class Foo

Answer 5

Question 6

True or False: The code shown in Listing 6 will compile and run successfully producing the output shown in Figure 6 .

Listing 6 - Question 6.
/*File Q06.java ************************************************/import java.awt.Frame; import javax.swing.JInternalFrame;import java.awt.Container; /*Frame and JInternalFrame are both subclasses of Container. Both classes define a constructorthat accepts a String as a title. Both classes define a method named getTitle that returns thetitle string. */public class Q06{ public static void main(String[]args){ Foo<Frame>fFoo = new Foo<Frame>( new Frame("Frame title"));System.out.println(fFoo.get().getTitle()); displayClass(fFoo);}//end main //-------------------------------------------//static void displayClass(Foo<Container>obj){ System.out.println(obj.getClass());}//end displayClass }//end class Q06//=============================================// class Foo<T extends Container>{ private T obj;public Foo(T obj){ this.obj = obj;}//end constructor public T get(){return obj; }//end get}//end Foo //=============================================//
Figure 6 - Question 6.
Frame title class Foo

Answer 6

Figures

Listings

What is the meaning of the following two images?

These images were inserted here simply to insert some space between the questions and the answers to keep them from being visible on the screen at thesame time.

Spacer image of a rabbit and a penguin.

This image was also inserted for the purpose of inserting space between the questions and the answers.

Spacer image of a penguin and some houses.

Answers

Answer 6

False. This program illustrates that you cannot pass an object of a parameterized class to a method that is designed to accept an incoming parameterof that class with a specific type of parameter that is a superclass of the actual type of parameter. An attempt to compile the program results in the errorshown in Figure 7 .

Figure 7 - Answer 6.
Q06.java:29: error: method displayClass in class Q06 cannot be applied to given types;displayClass(fFoo); ^required: Foo<Container>found: Foo<Frame>reason: actual argument Foo<Frame>cannot be converted to Foo<Container>by method invocation conversion 1 error

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Answer 5

False. This program illustrates that you cannot pass an object of a parameterized class to a method that is designed to accept an incoming parameterof that class with a specific type of parameter that is a superclass of the actual type of parameter. An attempt to compile the program results in the errorshown in Figure 8 .

Figure 8 - Answer 5.
Q05.java:23: error: method displayClass in class Q05 cannot be applied to given types;displayClass(iFoo); ^required: Foo<Number>found: Foo<Integer>reason: actual argument Foo<Integer>cannot be converted to Foo<Number>by method invocation conversion 1 error

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Answer 4

True. This program illustrates passing an object of a parameterized class to a method that is designed to accept an incoming parameter of that class witha specific type of parameter.

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Answer 3

True. This program illustrates passing an object of a parameterized class to a method that is designed to accept an incoming parameter of that class with aspecific type of parameter.

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Answer 2

True. This program illustrates the successful use of bounded type parameters.

Back to Question 2

Answer 1

True. This program illustrates the successful use of bounded type parameters. It also illustrates the use ofautoboxing to encapsulate primitive types int and double into objects of the wrapper classesInteger and Double.

Back to Question 1

Miscellaneous

This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Java4250r: Review of Generics, Inheritance, and Subtypes
  • File: Java4250r.htm
  • Published: 10/20/13
Disclaimers:

Financial : Although the Connexions site makes it possible for you to download aPDF file for this module at no charge, and also makes it possible for you to purchase a pre-printed version of the PDF file, youshould be aware that some of the HTML elements in this module may not translate well into PDF.

I also want you to know that, I receive no financial compensation from the Connexions website even if you purchase the PDF version ofthe module.

In the past, unknown individuals have copied my modules from cnx.org, converted them to Kindle books, and placed them for sale onAmazon.com showing me as the author. I neither receive compensation for those sales nor do I know who does receive compensation. If youpurchase such a book, please be aware that it is a copy of a module that is freely available on cnx.org and that it was made andpublished without my prior knowledge.

Affiliation : I am a professor of Computer Information Technology at Austin Community College in Austin, TX.

-end-

Questions & Answers

what is profit maximizing level of out put for above hypothetical firm TC = Q3 - 21Q2 + 600 + 1800 P = 600 MC = 3Q2 - 42Q + 600
Sosna Reply
what is labor productivity
Lizzy Reply
if the demand function is q=25-4p+p² 1.find elasticity of demand at the point p=5?
Puja Reply
what are some of the difference between monopoly and perfect competition market
Obeng Reply
n a perfectly competitive market, price equals marginal cost and firms earn an economic profit of zero. In a monopoly, the price is set above marginal cost and the firm earns a positive economic profit. Perfect competition produces an equilibrium in which the price and quantity of a good is economic
Naima
what are some characteristics of monopoly market
Obeng Reply
explicit cost is seen as a total experiences in the business or the salary (wages) that a firm pay to employee.
Idagu Reply
what is price elasticity
Fosua
...
krishna
it is the degree of responsiveness to a percentage change in the price of the commodity
Obeng
economics is known to be the field
John Reply
what is monopoly
Peter Reply
what is taxation
Peter
why do monopoly make excess profit in both long run and short run
Adeola Reply
because monopoly have no competitor on the market and they are price makers,therefore,they can easily increase the princes and produce small quantity of goods but still consumers will still buy....
Kennedy
how to identify a perfect market graph
Adeola Reply
what is the investment
jimmy
investment is a money u used to the business
Mohamed
investment is the purchase of good that are not consumed today but are used in the future to create wealth.
Amina
investment is the good that are not consumed
Fosua
What is supply
Fosua
 Supply represents how much the market can offer.
Yusif
it is the quantity of commodity producers produces at the market
Obeng
what is the effect of scarce resources on producers
Phindu Reply
explain how government taxes and government producer subsidies affect supply
Chanda
what is economic
Charles Reply
what are the type of economic
Charles
macroeconomics,microeconomics,positive economics and negative economics
Gladys
what are the factors of production
Gladys
process of production
Mutia
Basically factors of production are four (4) namely: 1. Entrepreneur 2. Capital 3. Labour and; 4. Land but there has been a new argument to include an addition one to the the numbers to 5 which is "Technology"
Elisha
what is land as a factor of production
Gladys
what is Economic
Abu
economics is how individuals bussiness and governments make the best decisions to get what they want and how these choices interact in the market
Nandisha
Economics as a social science, which studies human behaviour as a relationship between ends and scarce means, which have alternative uses.
Yhaar
Economics is a science which study human behaviour as a relationship between ends and scarce means
John
Economics is a social sciences which studies human behavior as a relationship between ends and scarce mean, which have alternative uses.....
Pintu
how will a country's population be equal to it's labour force
Hope Reply
what is the meaning of ppf
Obeng Reply
Production Possibility Frontier
Igbekele
What is Economic
Governor Reply
economic
Nwosu
Economics is the social science that deals with the unlimited human wants in the face of scarce (limited in supply) resources.
Azka
Difference between extinct and extici spicies
Amanpreet Reply
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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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