How to write custom exception in Java?

Question

Given,
the total levels in a hill pattern (input1),
the weight of the head level (input2), and
the weight increments of each subsequent level (input3),
you are expected to find the total weight of the hill pattern.

"Total levels" represents the number of rows in the pattern.
"Head level" represents the first row.
Weight of a level represents the value of each star (asterisk) in that row.

The hill patterns will always be of the below format, starting with 1 star at head level and increasing 1 star at each level till level N.

*
**
***
****
*****
******

. . .and so on till level N

Example1 -
Given,
the total levels in the hill pattern = 5 (i.e. with 5 rows)
the weight of the head level (first row) = 10
the weight increments of each subsequent level = 2
Then, The total weight of the hill pattern will be calculated as = 10 + (12+12) + (14+14+14) + (16+16+16+16) + (18+18+18+18+18) = 10 + 24 + 42 + 64 + 90 = 230

Example2 -
Given,
the total levels in the hill pattern = 4
the weight of the head level = 1
the weight increments of each subsequent level = 5
Then, Total weight of the hill pattern will be = 1 + (6+6) + (11+11+11) + (16+16+16+16) = 1 + 12 + 33 + 64 = 110

Answer 1

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

A simple example of custom exception is shown below:-

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;
    }


}