RESTful Web Services

It is pretty straight forward to build. Question is why you need to build this way....Simple answer is, it helps in scaling the deployment, ease in development/dev-ops in distributed systems. Most importantly, you an build self contained services that can expose its functionality to internal/external clients in constant way.

Topic to consider are

1.Best Methodologies and Conventions for building REST APIs. Ignore lot of opinions and use common sense.

2. Tools to Marshaling/Un-Marshaling Objects to JSON and vice Versa.

3. Handling Requests(How to build best controllers) and extract data from that and how to build responses.

I suggest read something like below, if is self-explaining.

https://spring.io/guides/gs/rest-service/

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