Java Constructors

Question 1

It is a special method that is used to initialize objects.

Answer 1

Constructor

Question 2

This is called when an object of a class is created. It can be used to set initial values for object attributes.

Answer 2

Constructor

Question 3

In java, a _____ is a block of codes similar to the method. It is called when an instance of the class is created. At the time of calling it, memory for the object is allocated in the memory.

Answer 3

Constructor

Question 4

It is a special type of method which is used to initialized the object.

Answer 4

Constructors

Question 5

Every time an object is created using the _____ keyword, at least one constructor is called.

Answer 5

new()

Question 6

Rules for creating Java Constructor (3):

Answer 6

• Constructor name must be the same as its class name
• Must have no return type
• Cannot be abstract, static, final, and synchroized

Question 7

Types of Java Constructor (2):

Answer 7

• Default Constructor
• Parameterized Constructor

Question 8

A constructor is called ______ when it doesn’t have any parameter.

Answer 8

Default Constructor

Question 9

<class_name>()
{

}
</class_name>

Answer 9

Syntax of default constructor

Question 10

If there is no constructor in a class, compiler _________ a default constructor.

Answer 10

automatically creates

Question 11

Purpose of a default constructor:

Answer 11

• Provide default values to the object like 0, null, etc., depending on the type.

Question 12

A constructor which has a specific number of parameters is called

Answer 12

Parameterized Constructor

Question 13

Why use Parameterized Constructor?

Answer 13

• used to provide different values to distinct objects. However, you can provide the same values also.

Question 14

In Java, a _______is just like a method but without return type. It can also be overloaded like Java methods.

Answer 14

Constructor

Question 15

a technique of having more than one constructor with different parameter lists. They are arranged in a way that each constructor performs a different task. They are differentiated by the compiler by the number of parameters in the list and their types.

Answer 15

Constructor Overloading

Question 16

Difference Between constructor and method in Java (5)(5):

Answer 16

Constructor:
1. Used to Initialize the state of an object.
Method:
1. Used to expose the behavior of an object

Constructor:
2. Must not have a return type.
Method:
2. A method must have a return type.

Constructor:
3. invoked implicitly
Method:
3. Invoked Explicitly

Constructor:
4. compiler provides a default constructor if you don’t have any constructor in a class.
Method:
4. Not provided by the compiler in any case

Constructor:
5. name must be same as the class name.
Method:
5. method name may or may not be same as the class name.