Trying to read a file, and it gives me "java.io.IOException"

I'm writing a little swing text editor for my first java project, and the open method is like this:
public void openFile() throws IOException {
               JFileChooser chooseOpen = new JFileChooser();
               chooseOpen.showOpenDialog(null);
               File openFile = chooseOpen.getSelectedFile();
               FileReader in = new FileReader(openFile);
               BufferedReader br = new BufferedReader(in);
               String fileText = br.readLine();
               output.setText(fileText);
It seems like it should work fine to me, you choose a file, and it opens it, then outputs it to my textArea. I even have it throwing IOException. Why is it giving me that message then? (this is the only method I'm having a problem with.)
the full error message is:
unreported exception java.io.IOException; must be caught og declared to be thrown
openFile();
^
1 error
thanks,
alex

openFile throws an IOException. This is a checked exception which means you must either put it in a try/catch block or throw it in the caller.

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