Question

The standard Exception has no default constructor (or a way to set the message after instantiation). If a custom exception is based on it, can the derived class be made injectable?

public class SpecialPurposeException extends Exception {

  private static final long serialVersionUID = 1L;

  public SpecialPurposeException(String message) {
    super(message);
  }
}

The custom exception will not normally be instantiated outside of its module, but for consistency reasons it should perhaps be injected inside of it.

Answer 1

1. There is a no-args for Exception. See Exception().

2. You cannot modified the value of the message String in Exception, but you can override the getMessage() method to return something different. That should be sufficient to allow you to inject a message … in various ways.