Combine GraphQL With Java to Build a Flexible and Modern API Avoid under-fetching and over-fetching data when retrieving data using REST APIs. by Join the DZone community and get the full member experience.Join For Free In the past few years, developers have used RESTful web services over HTTP(s) to expose business functions using an API. The REST API uses server-driven fixed data responses, which means a developer (client) can't determine the result of the response. Instead, the server sends all the data back to the client, which is called over-fetching. The developer (client) needs to invoke multiple REST APIs after the first call until the client gets the required data, which results in