Handling exceptions from methods in map of Optional

Question

I have a method like this.

@Override
public Optional<List<Order>> getPendingOrders(AuthDTO authDTO) throws MyException {
    return connector.getConnection(authDTO).map(p->p.getOrders());
}

Here

connector.getConnection(authDTO)

returns an Optional of Connection and

p->p.getOrders() 

throws KException which I cannot change and is of the form

public class KException extends Throwable {

    // variables
    public String message;
    public int code;

    // constructor that sets the message
    public KException(String message){
        this.message = message;
    }

    // constructor that sets the message and code
    public KException(String message, int code){
        this.message = message;
        this.code = code;
    }
}

and this the strucute of MyException

public class MyException extends KException {

    public MyException(String message, int code) {
        super(message, code);
    }
}

The code is not compiling with the below error

unreported exception com.something.exceptions.KException; must be caught or declared to be thrown

I want to convert this KException to MyException. Is there are an elegant way to do this? PLease help.

Answer 1

as suggested by some of the comments, you can trap the exception within the map operation and then perform any further logic you need to do:

return getConnection(authDTO).map(p -> {
        try {
            return p.getOrders();
        } catch (KException e) {
            // perform some other logic
        }
});

Answer 2

Cant you just do like this?

@Override
public Optional<List<Order>> getPendingOrders(AuthDTO authDTO) throws MyException {
    return connector.getConnection(authDTO)
            .map(p->p.getOrders())
            .orElseThrow(MyException::new));
            
}