What is the default value of variable when it is declared?

NULL
When a variable is first declared, its value is set to NULL.

What is the default value for a string variable that has been created but not initialised?

It’s not always necessary to assign a value when a field is declared. Fields that are declared but not initialized will be set to a reasonable default by the compiler. Generally speaking, this default will be zero or null , depending on the data type.

What is new keyword in Java?

The Java new keyword is used to create an instance of the class. In other words, it instantiates a class by allocating memory for a new object and returning a reference to that memory. We can also use the new keyword to create the array object.

Which variables are initialized by default value?

Method local variables need to be initialized before using them. In the second code sample, a is class member variable, hence it will be initialized to the default value. I notice method local array variables do not give the ‘variable a might not have been initialized’ when used.

What variables are given default values Java?

Instance variables have default values. For numbers, the default value is 0, for Booleans it is false, and for object references it is null. Values can be assigned during the declaration or within the constructor.

When you declare a variable in C it will have a default value of 0?

Unlike some programming languages, C/C++ does not initialize most variables to a given value (such as zero) automatically. Thus when a variable is assigned a memory location by the compiler, the default value of that variable is whatever (garbage) value happens to already be in that memory location!

What does it mean when a variable has not been initialized?

Initializing a variable means specifying an initial value to assign to it (i.e., before it is used at all). Notice that a variable that is not initialized does not have a defined value, hence it cannot be used until it is assigned such a value.

Which of the following is the default value assigned to a variable of type string if the variable is not explicitly initialized?

If there are no constructors written for a class, Java provides a no-argument default constructor where the instance variables are set to their default values. For int and double variables, the default value used is 0, and for String and other object variables, the default is null.

What is the use of new keyword?

New keyword in JavaScript is used to create an instance of an object that has a constructor function. On calling the constructor function with ‘new’ operator, the following actions are taken: A new empty object is created.

What’s the purpose of keyword new?

new is a Java keyword. It creates a Java object and allocates memory for it on the heap. new is also used for array creation, as arrays are also objects.

What is default value of int variable?

0
Variables of type “int” have a default value of 0.

What is the meaning of default value in Java?

Variables declared inside a class are known as member variables (static or non static). When variable is of any class type (non-primitive type), then it is known as reference variable, and it contains null value as a default value. …