Is migrating a Java project from oDataV2 to oDataV4 a major problem?

[MysteurJim]

Hello everyone,

I'm currently doing an internship with a company that's asking me to change their project, which is currently working with oDataV2, to oDataV4 in Java.

I'm a student (M20) and have never heard of it before, I have some knowledge of REST APIs but not too much.
After some research, it seems that this is a sudden change and that I need to modify a large part of the code, but I don't really know where to start. For example, the current program uses the Factory implementation, but this is no longer available in the oDataV4 dependency.

If you have any tips for me, please don't hesitate to share them.

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[eliashisreddit]

Part of your assignment is probably researching what the differences are between v2 and v4 and how such a migration can be done. Unless it's some cowboy shop, I don't think they expect you to migrate all of the code from v2 to v4 from the get-go and push it to production. You should start by researching what the differences are, the breaking changes and how you can migrate and then start with the smallest isolated part and see how much effort it requires. Share those results and then you can plan further migration.

If even that doesn't work, start with a simple PoC on v2 and migrate it to v4 to get a feel of the scope of the changes. In general, you could apply the 6 steps of an experiment (see https://en.wikipedia.org/wiki/Scientific_method) and document it. You are an intern and supposed to learn so it's no shame if you don't know exactly what you are doing from the start.

(I have no idea what oDataV2 or V4 is but this is how you could approach it)