Topic 2.2: Working With Java Data Types - Differentiate between object reference variables and primitive variables

Question 1

What default values are assigned to uninitialized primitive variables?

Answer 1

Uninitialized primitive variables are assigned default values:

• 0 for numeric types,
• false for boolean,
• and ‘\u0000’ for char.

Question 2

What does a
primitive variable
store when assigned a value?

Answer 2

This stores the actual value assigned to it.

Question 3

Name the eight primitive data types in Java.

Answer 3

The eight primitive data types in Java are:

byte, short, int, long, float, double, char, and boolean.

Question 4

How do primitive variables and object reference variables differ?

Answer 4

Primitive variables hold simple data values directly, while object reference variables hold references (memory addresses) to objects.

Question 5

What does an
object reference variable
store when assigned an object?

Answer 5

This stores the memory address of the assigned object.

Question 6

What do
object reference variables
store?

Answer 6

These store references (memory addresses) to objects.

Question 7

These store references (memory addresses) to objects.

Answer 7

What do
object reference variables
store?

Question 8

What default value is assigned to an uninitialized object reference variable?

Answer 8

An uninitialized object reference variable is assigned the default value of null.

Question 9

This stores the memory address of the assigned object.

Answer 9

What does an
object reference variable
store when assigned an object?

Question 10

This stores the actual value assigned to it.

Answer 10

What does a
primitive variable
store when assigned a value?