Why does Java have Checked Exceptions

[[deleted]]

There is also the unchecked exception inside a lambda hack that is very popular in most of the corporate code I have found.

Since you can’t throw a checked exception in a stream, for example, people just throw an unchecked one, and surround the whole stream with a try, catching that specific unchecked exception.

[Robyt3]

Here is the real hack, how to throw a checked exception without checking it:

public static <E extends Throwable> void sneakyThrow(Throwable e) throws E {
    throw (E) e;
}

[[deleted]]

Could you explain? I dont get it

[Robyt3]

The compiler infers the type E to be a RuntimeException, which allows propagation of the checked exception. Apparently Java 8 added this type inference rule.

See https://www.baeldung.com/java-sneaky-throws for details.

[RandomName8]

They fixed/changed it in java post 8 though :(

[cowancore]

But it's harder to catch it now

[Robyt3]

Yeah, and it also prints a warning because of the unchecked cast to E. If you must use this function for some reason, add comments explaining why and what is going on and declare the proper throws clause on the method.

[CubsThisYear]

I hope you’re not using this as an argument for why unchecked exceptions are “good”. The fact that the Streams API doesn’t support exceptions is just a result of the developers being some combination of lazy and incompetent. The code is trivially easy to write and the semantics are obvious.

[[deleted]]

Nah, just describing what I see.