> Why create a separate type over this class which is just a projection of its data? Because it lets you refactor your API separately from your domain. And use

> Why create a separate type over this class which is just a projection of its data? Because it lets you refactor your API separately from your domain. And use the full power of the IDE/typechecker in both cases. This approach especially shines with JAX-RS; you can write fully typed tests against your API methods, which look like pure logic functions.