Java Variable Interview Questions 1
What is variable in java?
Variable is like a container that is use to hold value of different data type.
You need to specify the data type of the variable while declaring it to make it clear what kind of value it will be storing.
To use a variable, a programmar needs to:
declare a variable
initialize the variable
then use it
For example. if we want to store a int value:
public int num; //declare variable num
num=11; //initialize value to variable num
We have discussed in details about variable, declaration, initialization and different types of variable in details here: Click to read
How many types of variable are there?
We have following types of variable available in java:
To learn in detail about each of them with examples click here
You can study answers about the next three questions following the same link.
What is local variable?
A variable declared inside method, block or loop is known as local variable.
Their scope or visibility is local to the entity in which they are declared. They cannot be used outside these entity.
A local variable should be initialized before use otherwise compiler error will occur.
Click here to read more about local variable with example
What is static variable?
Static variables are also referred to as class variable as they belongs to a class.
We can declare a static variable using static keywords.
Static variable is shared among different instances of a class. So static variables requires less storage memory space than instance variables.
Click here to read more about static variable with example
What is instance variable?
An instance variable is used by objects to store their states.
Each instance or object will have separate value which cannot be shared by other instances.
If value is not assigned for default variable then default value is assigned to it during run time.
Click here to read more about instance variable with example