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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

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
tijani
what is titration
John Reply
what is physics
Siyaka Reply
A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
Jude
what is the dimension formula of energy?
David Reply
what is viscosity?
David
what is inorganic
emma Reply
what is chemistry
Youesf Reply
what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
Adjei
please, I'm a physics student and I need help in physics
Adjanou
chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
Sahid Reply
you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
Ryan
what's motion
Maurice Reply
what are the types of wave
Maurice
answer
Magreth
progressive wave
Magreth
hello friend how are you
Muhammad Reply
fine, how about you?
Mohammed
hi
Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
yasuo Reply
Who can show me the full solution in this problem?
Reofrir 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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