Types of constructor in java

There are 3 types of constructor in java

Default constructor

Parameterized constructor

Parameterless constructor

Default constructor

 If we do not define any constructor then compiler generates one constructor for class is called default constructor.

 Compiler generated default constructor is parameterless.

 Compiler never generate default parameterized constructor, if we want to define instance of a class by passing arguments then we must define parameterized constructor inside class

Parameterized Constructor

If we define constructor of a class having one or more parameter then it is called parameterized constructor.

 When we create instance of a class by passing arguments then matching parameterized constructor gets called.

 Example:

public Employee(int empId,String empName,String companyName)

{

}

Employee employee=new Employee(123,”bob”,”Vodafone”)

ParameterlessConstructor

If we define constructor of a class without any parameter then it is called parameterless constructor or zero argument constructor.

 When we create instance of a class without passing any argument then parameterless constructor of a class get called.

 It is also called as zero argument constructor or user defined default constructor.

 Example:

public Employee(){ }

Employee employee=new Employee()

constructorchaining

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