Parametrized Constructor VS Default Constructor In Java 2023

What We Are Learn On This Post

Default constructor vs Parametrized constructor: In this article, we will list the difference between the default constructor and parameterized constructor in Java. Let us detail out the difference between the Default constructor v/s Parametrized constructor in the tabular form below.

Default Constructor vs Parametrized Constructor

Default constructor	Parameterized constructor
A constructor which takes no arguments is known as the default constructor	A constructor which takes one or more arguments is known as parameterized constructor
The compiler inserts a default no-arg constructor after compilation if there is no explicit constructor defined in a class	When the parameterized constructor is defined in a class, then the programmer needs to define default no-arg constructor explicitly if required
No need to pass any parameters while constructing new objects using the default constructor	At least one or more parameters need to be passed while constructing new objects using argument constructors
A default constructor is used for initializing objects with the same data	Whereas parametrized constructor is used to create distinct objects with different data

Example for Default constructor vs Parametrized constructor

Read Also: Difference Between Final Finally and Finalize

Employee.java

package in.bench.resources.constructor.example;
public class Employee
{
    // member variables
    int employeeId;
    String employeeName;
    String employeeOrg;
    
    // default constructor
    Employee() 
   {
      // an implicit super() constructor call to java.lang.Object is always present until we specify explicitly
      System.out.println("Employee class >> Inside default constructor");
      this.employeeOrg = "Google Corporation Inc.";
       }
    
   // parametrized constructor with 2 argument (String, int)
   Employee(String name, int id) 
   {
      this(); // to invoke another constructor from same class, this() constructor is used
      System.out.println("Employee class >> Inside parametrized constructor with 1 argument (String)");
      this.employeeName = name;
      this.employeeId = id;
   }
    
   //display() method
   void displayEmployeeInfo() 
   {
      System.out.println("\nEmployee details:\n\nOrgnaization:" + employeeOrg + "\nId: "+employeeId +"\nName: " + employeeName + "\n");
   }
    
   public static void main(String args[]) 
   {
         Employee emp = new Employee("Rahul Dravid", 19);
         emp.displayEmployeeInfo();
       }
}

Output:

Employee class >> Inside default constructor
Employee class >> Inside parametrized constructor with 1 argument (String)
 
Employee details: 
 
Orgnaization: Google Corporation Inc.
Id: 19
Name: Rahul Dravid