try-catch-finally with return after it

Question

I know how try, catch & finally work (for most part), but I have one thing I was wondering: what happens with a return statement after a try-catch-finally, while we already had a return in the try (or catch)?

For example:

public boolean someMethod(){
    boolean finished = false;
    try{
        // do something
        return true;
    }
    catch(someException e){
        // do something
    }
    finally{
        // do something
    }
    return finished;
}

Let's say nothing went wrong in the try, so we returned true. Then we will go to the finally where we do something like closing a connection, and then?

Will the method stop after we did some stuff in the finally (so the method returned true in the try), or will the method continue after the finally again, resulting in returning finished (which is false)?

Thanks in advance for the responses.

Answer 1

The fact that the finally block is executed does not make the program forget you returned. If everything goes well, the code after the finally block won't be executed.

Here is an example that makes it clear:

public class Main {

    public static void main(String[] args) {
        System.out.println("Normal: " + testNormal());
        System.out.println("Exception: " + testException());
    }

    public static int testNormal() {
        try {
            // no exception
            return 0;
        } catch (Exception e) {
            System.out.println("[normal] Exception caught");
        } finally {
            System.out.println("[normal] Finally");
        }
        System.out.println("[normal] Rest of code");
        return -1;
    }

    public static int testException() {
        try {
            throw new Exception();
        } catch (Exception e) {
            System.out.println("[except] Exception caught");
        } finally {
            System.out.println("[except] Finally");
        }
        System.out.println("[except] Rest of code");
        return -1;
    }

}

Output:

[normal] Finally
Normal: 0
[except] Exception caught
[except] Finally
[except] Rest of code
Exception: -1

Answer 2

If all goes well, return inside the try is executed after executing the finally block.

If something goes wrong inside try, exception is caught and executed and then finally block is executed and then the return after that is executed.

Answer 3

In that case the code inside the finally is run but the other return is skipped when there are no exceptions. You may also see this for yourself by logging something :)

Also see this concerning System.exit: How does Java's System.exit() work with try/catch/finally blocks?

And see returning from a finally: Returning from a finally block in Java

Answer 4

public int Demo1()
    {
        try{
            System.out.println("TRY");
            throw new Exception();
            }catch(Exception e){
                System.out.println("CATCH");
            }finally{
                System.out.println("FINALLY");
            }return 0;

    }

the output of call to this method is like this

TRY
CATCH
FINALLY
0

Means Consider Try{}catch{}finally{} as sequence of statements executed one by one In this particular case. And than control goes to return.

Answer 5

Definitely the code inside try will execute.. but when it reaches to return statement.. it will move to the finally block without executing the return statement in try block.. and then the code of finally will be executed and then the return statement of try will execute.