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Android

Posted by Jake Nagle
Jake Nagle
2,942 Points

Need a little help with the logic of catch/try and exceptions...

I'm working on the weather app project and need some review with try/catch blocks and throwing exceptions. Basically, I've made this code:

public void onResponse(Response response) throws IOException {
                try {
                    Log.v(TAG, response.body().string());
                    if (! response.isSuccessful()) {
                        alertUserAboutError();
                    }
                } catch (IOException e) {
                    Log.e(TAG,"Exception caught: ", e);
                }

            }

And it works, but I don't understand how/why. Can you break down what's going on? Also, I've noticed that taking out the Log.v line creates an error. Why is that?

Thank you very very much!

Ben Deitch
Ben Deitch
Treehouse Teacher
Ben Deitch
Ben Deitch
Treehouse Teacher

I added the word java after your first set of 3 backticks. That's the secret to making the code coloring appear. What error does taking our the Log.v line create?

1 Answer

Ozhan Saat
Ozhan Saat
Courses Plus Student 4,002 Points

If you take out the Log.v line then its not trying anything. Try to read it like a story.

Try this action If no response (! resonse.isSuccessful) Alert the user about the Error

The catch block is there to catch the exception so your app doesn't crash. The app is expecting a response and when it doesn't get one it throws an exception. This can crash your app but instead you contain it and give the user a error message. An example could be trying to open a web page when you're not connected to the internet.

Jake Nagle
Jake Nagle
2,942 Points

This makes sense. Thanks very much!