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#JAVA CONSTRUCTOR METHOD HOW TO#

Constructors are automatically called when an object is created.Constructors name must be similar to that of the class name inside which it resides.An abstract class can have the constructor.Constructors do not have a return type not even void.A constructor cannot be abstract, static, final, native, strictfp, or synchronized.

An interface cannot have the constructor.

The constructor in Java cannot be abstract, static, final or synchronized and these modifiers are not allowed for the constructor. Every class has a constructor when we don't explicitly declare a constructor for any java class the compiler creates a default constructor for that class which does not have any return type. It is named such because, it constructs the value, i.e., provide data for the object, i.e., they are used to initialize objects.

Java constructors are invoked when their objects are created. It is treated as a special member function because its name is the same as the class name. Here, in this chapter, you will be dealing with constructors of Java, and learn about how they are used within a Java program and how they are useful Object Oriented Programming concept.Ĭonstructors are special member functions whose task is to initialize the objects of its class. The second approach takes the help of method like getData() or init() etc., to initialize each object individually using statements like: It can be a tedious approach to initialize all the variables of the object in this manner. The first way of doing this is to use the dot operator to access the instance variable and then to assign values to them individually.

#JAVA CONSTRUCTOR METHOD HOW TO#

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➤ Overloading and Overriding Differences.

➤ Runtime and Compile-time Polymorphism.

➤ Overflow Underflow Widening Narrowing.