Best way to ensure streams that are opened inside a method call get closed

Question

I'm calling a method to write some data to a CSV file in java. Inside that method, I'm using a FileWriter that throws an IOException. I'm wondering what the correct way to handle this exception is if I want to handle it in the outer method while also ensuring that the FileWriter gets closed.

I am thinking of two solutions:

1. Just handle the exception inside the method that opens the FileWriter.

2. Figure out a way to pass the FileWriter back to the calling method so that it may be closed.

Here's an example of what I'm talking about:

public static void outerFunc() {
    // get some sort of data
    try {
        innerFunc(data);
    }
    catch (IOException e) {
        e.printStackTrace();
    }
    finally {
        // can I close the FileWriter here somehow?
    }
}

private static void innerFunc(Data data) throws IOException {
    FileWriter csv = new FileWriter("result.csv")

    // Write the data to the file

    csv.flush();
    csv.close();
}

Let me know what you guys think. I'm very open to the fact that I may be completely off base here and should be doing this a different way. Thank you in advance for any input!

Answer 1

The method that opens the resource should close it, and I would use the try-with-resources Statement. Like,

try (FileWriter csv = new FileWriter("result.csv")) {
    // ...
}