} catch (ExceptionA exception) {
    …
} catch (ExceptionB exception) {
    …
} catch (ExceptionC exception) {
    …
}

It’s a chain of if statements in disguise.

if (throwable instanceof ExceptionA) {
    ExceptionA exception = (ExceptionA) throwable;
    …
} elseif (throwable instanceof ExceptionB) {
    ExceptionB exception = (ExceptionB) throwable;
    …
} elseif (throwable instanceof ExceptionC) {
    ExceptionC exception = (ExceptionC) throwable;
    …
}

It is very much the kind of code that is disliked by OOP purists. It’s the way we implement polymorphism, when we don’t have control over the implementation of the callee [i].

Usually, polymorphism is achieved by defining functions on the callee. With exception handling, the handling needs to be defined by the caller, because each caller needs a different handling process.

[i] Google “External Polymorphism” for similar concepts.

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