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Thus, the contract for the add method of an object of a class that implements the Set interface is more specialized than the contract for the add method of an object of a class that implements the Collection interface.

An additional stipulation on the constructor for a Set object is that all constructors must create a set that contains no duplicate elements.

Stipulations on SortedSet

The SortedSet interface extends the Set interface. The SortedSet interface contains the following stipulation that makes it more specialized than a Set .

"A set that further guarantees that its iterator will traverse the set in ascending element order, sorted according to the natural ordering of itselements (see Comparable ), or by a Comparator provided at sorted set creation time."

We will end with a quiz

I'm going to finish this module with several questions in the form of a quiz. To ensure that this is a learning experience, I will provide an explanation inaddition to the answer for each question.

Question 1

True or False? A collection that implements the List interface maintains its elements in ascending alphanumeric order.

The answer to question 1 is False. Unlike collections that implement the SortedSet interface, the order of the elements in a collection that implements the List interface is not based on the values of the objects referred to by the elements in the list.

Question 2

True or False? A collection that implements the List interface is an unordered collection.

The answer to question 2 is also False. A collection that implements the List interface is an ordered collection (also known as a sequence) . According to Oracle, "The user of the interface has precise control over where in the list each element is inserted." Elements can be inserted and retrieved on the basis of their integer index (position in the list) using the following methods:

  • add(int index, Object element)
  • get(int index)

Valid index values are positive integers that begin with zero. When the add method is used to insert an element at a specific position in the sequence, the element currently at that position (if any) and any subsequent elements are shifted toward higher index values to make room for thenew element.

Another version of the add method takes a reference to an object as an incoming parameter and appends the specified element to the end of thecollection.

The get method simply returns the element at the specified position in the collection.

The List interface also declares various other methods that can be used to manipulate the contents of the collection.

Question 3

True or False? A collection that implements the List interface is allowed to contain duplicate values.

The answer to question 3 is True. Unlike a collection that implements the Set interface, a collection that implements the List interface is typically allowed to contain duplicate values. More formally, accordingto Oracle, "lists typically allow pairs of elements e1 and e2 such that e1.equals(e2), and they typically allow multiple null elements if they allownull elements at all."

Questions & Answers

anyone know any internet site where one can find nanotechnology papers?
Damian Reply
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.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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