Java Custom Exceptions

Java Custom Exceptions: (Exceptions here)
In Java, developer can customize the exceptions. The developer has to write a class that extends Exception and can customize the exception.

Before we proceed further, Let us try to understand two keywords throw and throws

Now let us see an example for Custom Exception,

package ExceptionHandling;
public class ExceptionHandling {
    
    class customException extends Exception{
        public customException(String s){
            super(s);
        }
    }
    
    public void validate(int i)throws customException{
        if(i>20){
            throw new customException("Not Qualified");
        }
        else
        {
            System.out.println("Qualified");
        }
        
    }
    
    public static void main(String args[]) throws customException{
       ExceptionHandling exceptionHandling = new ExceptionHandling();
       exceptionHandling.validate(22);
    }   
}

In the above example, We have declared throws customException. We can declare multiple exceptions there. Example: Throws IO Exception, Arithmetic Exceptions etc. But we will be able to declare throw only once within a method.

Output:

Exceptions – Here