DataBuffer interface needs reference to Spring Project and proper nullable annotations.

[agentgt]

Because the DataBuffer interface was more or less copied from Spring Project despite both jooby and spring being apache licensed you need a reference to it other than just the authors name.

I can't remember the exact way to do this with Apache but according to chatgpt (so you know it might not be right):

/*
 * This file is part of [Your Project Name].
 * 
 * It is derived from [Original Project Name], originally available at:
 * [URL of the original project]
 * 
 * [Original Project Name] is licensed under the Apache License, Version 2.0.
 * 
 * Modifications:
 * - [Briefly describe any changes you made]
 * 
 * [Your Project Name] is also licensed under the Apache License, Version 2.0.
 * 
 * See the LICENSE file in the root of this repository for details.
 */

Then in the LICENSE file:

This project includes code from [Original Project Name], which is licensed under the Apache License, Version 2.0.

[Original Project Name]:
[URL of the original project]

The original license is included below:

[Include the original Apache License text here or a reference to where it can be found in the original project]

Replace Original Project Name with Spring.

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As for the nullable annotations it appears the interface is missing @NonNull for all of its returns.

[edgar-espina-wpp]

@agentgt sure, please send a PR with all these changes.