Java - Does a finally block always get executed in Java

error-handlingjavareturntry-catch-finally

Considering this code, can I be absolutely sure that the finally block always executes, no matter what something() is?

try {  
    something();  
    return success;  
}  
catch (Exception e) {   
    return failure;  
}  
finally {  
    System.out.println("I don't know if this will get printed out");
}

Best Solution

Yes, finally will be called after the execution of the try or catch code blocks.

The only times finally won't be called are:

If you invoke System.exit()
If you invoke Runtime.getRuntime().halt(exitStatus)
If the JVM crashes first
If the JVM reaches an infinite loop (or some other non-interruptable, non-terminating statement) in the try or catch block
If the OS forcibly terminates the JVM process; e.g., kill -9 <pid> on UNIX
If the host system dies; e.g., power failure, hardware error, OS panic, et cetera
If the finally block is going to be executed by a daemon thread and all other non-daemon threads exit before finally is called

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Java - How does the Java ‘for each’ loop work

for (Iterator<String> i = someIterable.iterator(); i.hasNext();) {
    String item = i.next();
    System.out.println(item);
}

Note that if you need to use i.remove(); in your loop, or access the actual iterator in some way, you cannot use the for ( : ) idiom, since the actual iterator is merely inferred.

As was noted by Denis Bueno, this code works for any object that implements the Iterable interface.

Also, if the right-hand side of the for (:) idiom is an array rather than an Iterable object, the internal code uses an int index counter and checks against array.length instead. See the Java Language Specification.

C# - Is it bad practice to return from within a try catch finally block

No, it's not a bad practice. Putting return where it makes sense improves readability and maintainability and makes your code simpler to understand. You shouldn't care as finally block will get executed if a return statement is encountered.

Best Solution

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