I am creating a checkbook and am unable to create a file to write to for each separate account. When I try to create the file I get the error "unreported exception IOException; must be caught or declared to be thrown". I try to declare that my action listener method throws an exception but that makes the action listener method no longer able to work. I then tried to create a separate method that creates the file and is called by the button press but i still run into the same error
Here is my code:
public void actionPerformed(ActionEvent e) {
...
if (e.getSource() == create) {
creatNewAccount(name3.getText());
BALANCE = Double.parseDouble(name2.getText());
}
}
public void creatNewAccount(String s) throws IOException {
FileWriter fw = new FileWriter(s + ".txt", false);
}
IOException
is a checked exception. Given that you're calling it within an ActionListener
, rethrowing the exception is not an option so you need to catch it.
try {
creatNewAccount(name3.getText());
} catch (IOException e) {
e.printStackTrace();
// more exception handling
}
creatNewAccount
is declared as possibly throwing an IOException
. IOException
is not a RuntimeException
, so you must catch it.
if (e.getSource() == create) {
try {
creatNewAccount(name3.getText());
} catch (IOException ie) {
ie.printStackTrace();
// handle error
}
BALANCE = Double.parseDouble(name2.getText());
}
For more information, please read about The Catch or Specify Requirement and Catching and Handling Exceptions .
A few other things I noticed: - The word you're looking for is create , not creat . - You're assigning something to BALANCE
. Uppercase names are generally reserved for constants. Consider renaming this variable balance
. - Consider more descriptive names for your text fields. name2
and name3
don't really say much.
In your actionPerformed()
you need to put a try/catch block around the createNewAccount
call. What you do with the exception once caught is up to you -- an easy thing to do is to wrap it in a RuntimeException
which does not need to be caught (but might foul up your process until you do something more elaborate).
public void actionPerformed(ActionEvent e) {
...
if (e.getSource() == create) {
try {
creatNewAccount(name3.getText());
} catch( IOException ioe) {
System.err.println("Whoops! " + ioe.getMessage());
throw new RuntimeException("Unexpected exception", ioe);
}
BALANCE = Double.parseDouble(name2.getText());
}
}
It's likely you'll just need to catch the exception inside the method:
public void creatNewAccount(String s) {
try{
FileWriter fw = new FileWriter(s + ".txt", false);
} catch (IOException e){
//TODO something to handle the error
}
}
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