how to create a utility method which has checked exception?

Question

I have to set private InputStream responseMsg in my struts 2 application action class methods using following code

responseMsg = new ByteArrayInputStream(message.getBytes("UTF-8"));

in this case i have to handle UnsupportedEncodingException checked exception. I want to assign InputStream in so many action methods if i added throws UnsupportedEncodingException in all methods means code looks messy. so i decided to create utility method in a Utility class

public class Utilities {

    public InputStream responseMessage(String message) throws UnsupportedEncodingException {
        return new ByteArrayInputStream(message.getBytes("UTF-8"));
    }
}

invoked from my action class

responseMsg = new Utilities().responseMessage(message);

in this case also compile time error coming to handle UnsupportedEncodingException in action methods, help me to create Utility methods for all of my action class methods.

just handle the exception.... don't understand what you are asking. — T McKeown, Jul 28 '14 at 16:22
What are you saving with the Utility method? It would still throw UnsupportedEncodingException, and the callers of that method would have to handle it or declare that they throw it. — Eran, Jul 28 '14 at 16:24

score 1 · Accepted Answer · answered Jul 28 '14 at 16:34

If you are talking about "UTF-8" specifically, the recommended way is to throw an Error if something that must work by specification doesn’t. E.g.

public InputStream responseMessage(String message) {
  try {
    return new ByteArrayInputStream(message.getBytes("UTF-8"));
  } catch(UnsupportedEncodingException ex) {
    throw new AssertionError("Every JVM must support UTF-8", ex);
  }
}

Since Java 7 live is much easier for this specific case:

public InputStream responseMessage(String message) {
  return new ByteArrayInputStream(message.getBytes(StandardCharsets.UTF_8));
}

If it comes to arbitrary charsets, you should handle the possible exception, which is not a big deal as your code using the returned InputStream will have to deal with the declared IOExceptions anyway and UnsupportedEncodingException is a subclass of IOException. So the required catch or throws clause for IOException will cover UnsupportedEncodingException already.

how to create a utility method which has checked exception?

1 Answers1