clone() method in Java

We'll generally create clone, when we want to create local copy of the object and don't want to modify the original object.
Use the clone() method cautiously, or else you can also create a copy constructor alternative to the clone().
This is a protected method in java.lang.Object class.
protected Object clone() CloneNotSupportedException : It creates and returns a copy of this object.

By default shallow copy is applied. If we want extra logic to be impemented then we need to opt for deep copy.
Shallow copy : Just call the super.clone()
Deep copy : We need to implement ourselves.

A simple example
describing clone() method in Java:
Account.java

package com.clone.sample;

public class Account implements Cloneable {

 public Account(long acc_num,String name,String branch) {
  this.setAcc_num(acc_num);
  this.setName(name);
  this.setBranch(branch);
 }
 private long acc_num;
 private String name;
 private String branch;
 
 public void setAcc_num(long acc_num) {
  this.acc_num = acc_num;
 }
 
 public void setName(String name) {
  this.name = name;
 }
 public void setBranch(String branch) {
  this.branch = branch;
 }
 
 public Object clone() throws CloneNotSupportedException {
  return super.clone();
 }
 
 public String toString() {
  return "Acct No: " this.acc_num "\n" "Acct.holder's name : " name "\n" "Branch : " branch;
 }
}

CloneSample.java

package com.clone.sample;

public class CloneSample {
 public static void main(String[] args) {
  Account acc = new Account(68029,"Praveen","Hyderabad");
  System.out.println(acc);
  
  try {
   Account copyAcc = (Account) acc.clone();
   System.out.println("Shallow copy : \n" "[" copyAcc "]");
   System.out.println(acc.clone().getClass() == copyAcc.getClass()); // instances of same class
   System.out.println(acc.equals(copyAcc));
   System.out.println(acc.clone()!= copyAcc); 
  } catch (CloneNotSupportedException e) {
   e.printStackTrace();
  }
 }
} 

output: 

Acct No: 68029 

Acct.holder's name : Praveen 

Branch : Hyderabad 

Shallow copy : 

[Acct No: 68029 

Acct.holder's name : Praveen 

Branch : Hyderabad]

true 

false 

true