Different Ways to Create an Object in Java

       As we know, an object is a real-world entity that represents an instance of a class. This is a common interview question for freshers and Java developers with up to two years of experience. Understanding the different ways to create an object in Java is essential for interview preparation.

There are four ways to create an object in Java. In this post, we will discuss each method in detail along with practical examples.

1) Using new keyword

            
        This is the most common way to create an object in Java. Almost 99% of objects are created using this approach.

   e.g    Employee emp=new  Employee();

package com.adnjavainterview;

public class Employee {

     public String getName() {
          System.out.println("Object Creation Example");
     }

     public static void main(String[] args) {
           Employee emp = new Employee();
           emp.getName();
     }
}

Output:- Object Creation Example

2) Using Class.forName()

     
          If we know the name of the class and it has a public no-argument (default) constructor, we can create an object using this approach. The Class.forName() method loads the class into memory, and the newInstance() method of the Class object is then used to create an instance of the class.

Note for Java 9 and later

If your blog targets modern Java versions (Java 9+ or Java 17), it's worth mentioning that Class.newInstance() has been deprecated.

        Employee obj =(Employee)  Class..forName("com.adn.Employee").newInstance();

package com.adnjavainterview;

public class Employee {

     public String getName() {
          System.out.println("Object Creation Example");
     }

     public static void main(String[] args) {
           Employee emp = Class.forName("Employee").newInstance();
           emp.getName();
     }
}

Output:- Object Creation Example

3) Using clone()

        
         The clone() method is used to create a copy of an existing object. It copies the contents of the original object into a newly created object. To use the clone() method, the class must implement the Cloneable interface.

                 Employee emp=new Employee();
               Employee cloneObject=emp.clone();

public class Employee implements Cloneable { 
      @Override
      protected Object clone() throws CloneNotSupportedException { 
            return super.clone(); 
      } 
     
      public String getName() {
            System.out.println("Object Creation Example");
      }  
    
      public static void main(String[] args) { 
           Employee emp = new Employee(); 
           try { 
                Employee cloneObject = (Employee) emp.clone(); 
                System.out.println(cloneObject.getName()); 
           } 
           catch (CloneNotSupportedException e) { 
                e.printStackTrace(); 
           } 
      } 
} 

Output:- Object Creation Example

4) Using object deserialization

   
   Object deserialization is the process of creating an object from its serialized form.

               ObjectInputStream  inStream = new  ObjectInputStream(anInputStream);
                                     MyObject object = (MyObject) inStream.readObject(); 



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