# Description of Changes
Please provide a summary of the changes, including:
- **What was changed**
- **EmailController**: Added a `catch (MailSendException)` block to
handle invalid-address errors, log the exception, and return a 500
response with the raw error message.
- **EmailServiceTest**: Added unit tests for attachment-related error
cases (missing filename, null filename, missing file, null file) and
invalid “to” address (null or empty), expecting `MessagingException` or
`MailSendException`.
- **MailConfigTest**: New test class verifying `MailConfig.java`
correctly initializes `JavaMailSenderImpl` with host, port, username,
password, default encoding, and SMTP properties.
- **EmailControllerTest**: Refactored into a parameterized test
(`shouldHandleEmailRequests`) covering four scenarios: success, generic
messaging error, missing `to` parameter, and invalid address formatting.
- **Why the change was made**
- To ensure invalid email addresses and missing attachments are handled
gracefully at the controller layer, providing clearer feedback to API
clients.
- To improve overall test coverage and guard against regressions in
email functionality.
- To enforce correct mail configuration via automated tests.
---
## Checklist
### General
- [x] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [x] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md)
(if applicable)
- [x] I have performed a self-review of my own code
- [x] My changes generate no new warnings
### Documentation
- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)
### UI Changes (if applicable)
- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)
### Testing (if applicable)
- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/DeveloperGuide.md#6-testing)
for more details.
