How to write custom exception in Java?

We can extend Exception class or any of its subclasses to create our custom exception class. The custom exception class can have its own variables and methods that we can use to pass error codes or other exception related information to the exception handler.

package com.journaldev.exceptions;
import java.io.IOException;
public class MyException extends IOException {
 private static final long serialVersionUID = 4664456874499611218L;
 
 private String errorCode="Unknown_Exception";
 
 public MyException(String message, String errorCode){
 super(message);
 this.errorCode=errorCode;
 }
 
 public String getErrorCode(){
 return this.errorCode;
 }
}