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Answer 8

False. This is an unsuccessful call to a generic method where the type of the object passed to the method isabove the upper bound on the specified generic type for the method. An attempt to compile the program results in the errorshown in Figure 11 below.

Figure 11 - Answer 8.
Q08.java:25: error: method runIt in class Foo cannot be applied to given types;aFoo.runIt(aFrame); ^required: T found: Framereason: inferred type does not conform to declared bound(s) inferred: Framebound(s): JFrame where T is a type-variable:T extends JFrame declared in method<T>runIt(T) 1 error

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Answer 7

True. This is a successful call to a generic method where the generic type for the method is above (in the inheritance hierarchy) the type of object passed as a parameter.

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Answer 6

One possible solution is shown in Listing 8 below.

Listing 8 - Answer 6.
/*File A06Foo.java ************************************************/import java.awt.*; public class A06Foo<T extends Component>{ private T param;public A06Foo(T param){this.param = param; }//end constructorpublic void runIt(){System.out.println("Object instantiated."); System.out.println(param.getClass());}//end runIt }//end A06Foo//=============================================//

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Answer 5

One possible solution is shown in Listing 9 below where T extends Component . However, causing T to extend Window, Container, Component, or Object would all be valid solutions. The upper bound for T must be at or above thetype being passed as a type parameter in the inheritance hierarchy.

Listing 9 - Answer 5.
/*File A05Foo.java ************************************************/import java.awt.*; public class A05Foo<T extends Component>{ public void runIt(){System.out.println("Object instantiated."); }//end runIt}//end A05Foo //=============================================//

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Answer 4

False. This program produces the compiler error shown in Figure 12 below. The problem is that the upper bound for the type parameter in the class named Foo(Frame) is below the type passed as a parameter (Window) in the attempt to instantiate an object of the class named Foo.

Figure 12 - Answer 4.
Q04.java:20: error: type argument Window is not within bounds of type-variable TFoo<Window>aFoo = new Foo<>(); ^where T is a type-variable: T extends Frame declared in class FooQ04.java:20: error: cannot infer type arguments for Foo<>; Foo<Window>aFoo = new Foo<>(); ^reason: no instance(s) of type variable(s) T exist so that Foo<T>conforms to Foo<Window>where T is a type-variable: T extends Frame declared in class Foo2 errors

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Answer 3

True. A type variable with multiple bounds is a subtype of all the types listed in the bound. If one of the bounds is a class, it must be specified first.

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Answer 2

False. The correct statement is:

"To declare a bounded type parameter, list the type parameter's name, followed by the extends keyword, followed by its upper bound. Note that, in this context, extends is used in a general sense to mean either "extends" (as in classes) or "implements" (as in interfaces)."

Back to Question 2

Answer 1

True. There may be times when you want to restrict the types that can be used as type arguments in a parameterized type. For example, a method that operates on numbers might only want to accept instances of Number or its subclasses. This is what bounded type parameters are for.

Back to Question 1


This section contains a variety of miscellaneous information.

Housekeeping material
  • Module name: Java4240r: Review of Bounded Type Parameters
  • File: Java4240r.htm
  • Published: 10/19/13

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 compensationfor those sales nor do I know who does receive compensation. If you purchase such a book, please be aware that it is a copy of a modulethat is freely available on cnx.org and that it was made and published without my prior knowledge.

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


Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
analytical skills graphene is prepared to kill any type viruses .
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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