Does a finally block always get executed in Java?

Question

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

try         


        

Answer 1

Also, although it's bad practice, if there is a return statement within the finally block, it will trump any other return from the regular block. That is, the following block would return false:

try { return true; } finally { return false; }

Same thing with throwing exceptions from the finally block.

Answer 2

Also a return in finally will throw away any exception. http://jamesjava.blogspot.com/2006/03/dont-return-in-finally-clause.html

Answer 3

In addition to the point about return in finally replacing a return in the try block, the same is true of an exception. A finally block that throws an exception will replace a return or exception thrown from within the try block.

Answer 4

Yes It will. Only case it will not is JVM exits or crashes

Answer 5

Here's an elaboration of Kevin's answer. It's important to know that the expression to be returned is evaluated before finally, even if it is returned after.

public static void main(String[] args) {
    System.out.println(Test.test());
}

public static int printX() {
    System.out.println("X");
    return 0;
}

public static int test() {
    try {
        return printX();
    }
    finally {
        System.out.println("finally trumps return... sort of");
    }
}

Output:

X
finally trumps return... sort of
0

Answer 6

finally is always executed and before returning x's (calculated) value.

System.out.println(foo());

....

int foo(){
    int x = 2;
    try{
        return x++;
    } finally{
        System.out.println(x);
    }
}

Output:

3
2