What happens if a method throws an exception that was not specified in the method declaration with “throws”

Question

I\'ve never used the \"throws\" clause, and today a mate told me that I had to specify in the method declaration which exceptions the method may throw. However, I\'ve been u

Answer 1

Java has two different types of exceptions: checked Exceptions and unchecked Exceptions.

Unchecked exceptions are subclasses of RuntimeException and you don't have to add a throws declaration. All other exceptions have to be handled in the method body, either with a try/catch statement or with a throws declaration.

Example for unchecked exceptions: IllegalArgumentException that is used sometimes to notify, that a method has been called with illegal arguments. No throws needed.

Example for checked exceptions: IOException that some methods from the java.io package might throw. Either use a try/catch or add throws IOException to the method declaration and delegate exception handling to the method caller.