Should my persistence class return Option or rely on exceptions?

Question

The security level of my application is formed using the storage property and implementation class. I deviate from this problem: should methods fetchFoo(key: Key)return Option[Foo], or should they throw exceptions FooNotFoundif the key cannot be found?

To add flavor to the problem, the persistence layer — written in Scala — is called by Java code. Working with scala.Option in Java code? Hmmm.

In fact, until yesterday, the persistence layer was written in Java; I just rewrote it in scala. As a Java codebase, it relied on exceptions rather than returning zeros; but now that I am facing scala.Option, I am redefining. It seems to me that Scala is less in love with exceptions than Java.

Answer 1

My common problem is that it depends on where the keys are coming from.

If they are entered by any user or an unreliable system, I use Optionso that I can meaningfully indicate the possibility of an unknown key and deal with it accordingly.

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Answer 2

Java Option isEmpty, isDefined get - ( Option, getOrElse, .) isDefined if , try-catch.

Answer 3

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