Objects and Collections Questions and Answers
Practice ModeShowing 10 of 38 questions
Q1
Suppose that you would like to create an instance of a new Map that has an iteration order that is the same as the iteration order of an existing instance of a Map. Which concrete implementation of the Map interface should be used for the new instance?
Answer: Option C
Q2
Which class does not override the equals() and hashCode() methods, inheriting them directly from class Object?
Answer: Option C
Q3
Which collection class allows you to grow or shrink its size and provides indexed access to its elements, but whose methods are not synchronized?
Answer: Option D
Q4
You need to store elements in a collection that guarantees that no duplicates are stored. Which one of the following interfaces provide that capability?
Answer: Option A
Q5
You need to store elements in a collection that guarantees that no duplicates are stored and all elements can be accessed in natural order. Which interface provides that capability?
Answer: Option B
Q6
Which interface does java.util.HashTable implement?
Answer: Option A
Q7
Which interface provides the capability to store objects using a key-value pair?
Answer: Option A
Q8
Which collection class allows you to associate its elements with key values, and allows you to retrieve objects in FIFO (first-in, first-out) sequence?
Answer: Option B
Q9
Which collection class allows you to access its elements by associating a key with an element's value, and provides synchronization?
Answer: Option D
Q10
Which is valid declaration of a float?
Answer: Option A