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Java

Posted by Brandon DeJesus
Brandon DeJesus
2,994 Points

In Java Data Structures, why does Craig need to put "throws clause" on his method promptNewSong()? What does it do?

I noticed that Craig needed to throw a new IOException on the method header for promptAction() and on promptNewSong(). Both of these methods are located in KaraokeMachine class. He also puts a try/catch block in the method run(). Do these IOExceptions automatically know to look inside the try/catch block in the method run() or what purpose are they serving in this example in particular? The video that I am describing in particular is Menu UI video inside Java Data Structures course.

1 Answer

andren
andren
28,558 Points
andren
andren
28,558 Points

The throws keyword tells Java that the method does something that can cause a certain exception and that the method itself has no try/catch clause to deal with that potential exception, which means that the exception has to be handled by whatever ends up calling said method instead.

Since those methods are called within the run method that is where the potential exceptions will end up being thrown to if they actually occur, and therefore that's where a try/catch clause is needed.

So simply summarized throws is just a way of telling Java "Yes, I know there is a potentially unhandled exception in this method, but I don't want to deal with it right here so make the code that calls the method deal with it instead".

Brandon DeJesus
Brandon DeJesus
2,994 Points

Thank you for clarifying! andren