throws
Error message “unreported exception java.io.IOException; must be caught or declared to be thrown” [duplicate]
void showfile() throws java.io.IOException <—– Your showfile() method throws IOException, so whenever you use it you have to either catch that exception or again thorw it. Something like: try { showfile(); } catch(IOException e) { e.printStackTrace(); } You should learn about exceptions in Java.
Should I declare unchecked exceptions in the throws specification?
If for some reason I can reasonably expect an unchecked exception to occur in a method, should I add it to the throws specification? Since unchecked exceptions indicate programming errors, declaring them in the throws clause should be avoided. Generally, catching these exceptions should not be attempted, except for the highest level of your program. … Read more
Either re-interrupt this method or rethrow the “InterruptedException issue in sonar
To “re-interrupt” as a best practice: try{ //some code } catch (InterruptedException ie) { logger.error(“InterruptedException: “, ie); Thread.currentThread().interrupt(); } catch (ExecutionException ee) { logger.error(“ExecutionException: “,ee); } Usually, when a thread is interrupted, whoever is interrupting the thread, wants the thread to exit what it’s currently doing. However, make sure that you do NOT multi-catch: catch … Read more
Can I declare that a php function throws an exception?
You can use @throws in the PHPDoc comment, and the IDE will recognize this function as throwing an exception, when viewing the doc, however unlike Java it will not force you to implement the Try{}catch block. Maybe future versions of the IDE (I am using InteliJ 11) will mark those places where try{}catch is expected, … Read more
Difference between Throws in method signature and Throw Statements in Java
You are pretty much right on. Except for one thing I’ll mention in a bit. throws is as much a part of the method API as the name and the parameters. Clients know if they call that method, they need to handle that exception–by simply throwing it also or by catching it and handling it … Read more
Exception handling : throw, throws and Throwable
throws : Used when writing methods, to declare that the method in question throws the specified (checked) exception. As opposed to checked exceptions, runtime exceptions (NullPointerExceptions etc) may be thrown without having the method declare throws NullPointerException. throw: Instruction to actually throw the exception. (Or more specifically, the Throwable). The throw keyword is followed by … Read more
Throws or try-catch
catch an exception only if you can handle it in a meaningful way declare throwing the exception upward if it is to be handled by the consumer of the current method throw exceptions if they are caused by the input parameters (but these are more often unchecked)
When to use throws in a Java method declaration?
If you are catching an exception type, you do not need to throw it, unless you are going to rethrow it. In the example you post, the developer should have done one or another, not both. Typically, if you are not going to do anything with the exception, you should not catch it. The most … Read more
Is there a way to make Runnable’s run() throw an exception?
You can use a Callable instead, submitting it to an ExecutorService and waiting for result with FutureTask.isDone() returned by the ExecutorService.submit(). When isDone() returns true you call FutureTask.get(). Now, if your Callable has thrown an Exception then FutureTask.get() wiill throw an Exception too and the original Exception you will be able to access using Exception.getCause().