Object-Oriented Programming

It is used for reuse the code because all the properties of the base class inherit in child class.

This is the definition of data abstraction, which also describes the abstract data of the class.

This feature is not the advantage,  but it is related to OOPs.

It is the correct answer because constructor invoked automatically when object is created.

It is used for this purpose.

This operator is used for this purpose.

It is a description of set of sequence of actions that a system performs that yields an observable result of value to a particular actor.

Its objects represent elements whose behavior is concurrent with other elements.

This stream class is used in C++ to perform input and output operations on to a data file.

This stream class acts as base class in the hierarchy of file stream classes.

This is the correct choice because there are 3 constructors of HashMap class. These are:   HashMap(): creates a Map with default initial capacity and load factor HashMap(int initialCap, float load): creates a Map with default specified initial capacity and load factor HashMap(m : Map): creates a Map with existing Map

This is the correct choice because there are 4 constructors of HashTable class in Java collections framework. These constructors are: 1) Hashtable(): constructs a new, empty hashtable with a default initial capacity (11) and load factor (0.75) 2) Hashtable(int initialCapacity): constructs a new, empty hashtable with the specified initial capacity and default load factor (0.75) 3) Hashtable(int initialCapacity, float loadFactor): constructs a new, empty hashtable with the specified initial capacity and the specified load factor 4) Hashtable(Map t): constructs a new hashtable with the same mappings as the given map

This is the correct answer. There are four constructors of TreeMap. These are:

TreeMap(): It creates an empty Map. TreeMap(Comparator comp): The second form constructs an empty tree-based map that will be sorted by using the Comparator comp. TreeMap(Map m): The third form initialises a tree map with the entries from m, which will be sorted by using the natural order of the keys. TreeMap(SortedMap sm): The fourth form initialises a tree map with the entries from sm, which will be sorted in the same order as sm.

Abstract classes defines common properties and behaviors of other classes.

Serializable is a public interface to allow subtypes of non-serializable classes to be serialized. This interface is included in java.io. Serializable package has access specifier as public.