Is there any custom exception already in library which we can use where ever we want it to throw with custom message?

Question

I want to throw a run-time exception from a method which will be caught in another class, which in turn throws a further specific custom exception or does some operation.

    def checkExtension(String fileName,file) {

    String [] arr= Holders.config.bdmserver.defaultfile_ext
       for (int i=0; i < arr.length-1;i++) {
        println("file extension=" + fileName.substring(fileName.length() - 3))
        if (arr[i].equals(fileName.substring(fileName.length() - 4))) {
            println("in if becoz its either .zip or .exe")
            // throw run-time exception 
        }
    }

    def fileSize = (file.getSize())/12000
    if (fileSize > 5 ){
       // throw run-time exception 
    }


}

in different class

catch (run-time exception ex){
                 throw new ApplicationException(BdmsException, messageSource.getMessage("file.upload.failureExtension.message", "Error!! you can not upload a file with this extension", Locale.getDefault()), ex)
        }

How can I do it without creating a new custom exception class?

What is your aversion to just creating a custom exception in your project? — Tim Biegeleisen, Sep 11 '17 at 10:06
This is not Java. Scala perhaps? 'I want to throw a run-time exception from a method which will be caught in another class, which in turn throws a further specific custom exception': so why does it have to be a `RuntimeException`? — user207421, Sep 11 '17 at 10:13
first of all, its a groovy code. If you see the logic, its actually uploading a file and I want to throw an exception if someone try's to upload .exe file. — deepti mullur, Sep 11 '17 at 10:39
I can always create a custom exception but its just tedious job in this case as I have to follow the organization standards to create custom exception in jar by following other standards for that particular jar. — deepti mullur, Sep 11 '17 at 10:41
use IllegalArgumentException with proper message, though using a custom business exception is better — Sikorski, Sep 11 '17 at 10:44
that's so nice of you Jon. Thank you. I will re-post that question. — deepti mullur, Sep 13 '17 at 08:34

score 1 · Accepted Answer · answered Sep 11 '17 at 10:20

1

You can create your own exception type, with the message that you need, inheriting from RuntimeException. And in your code just put: throw new MyRuntimeException("Put message here");. This way you can be sure you are handling your own exception.

But, if you are not interested in handling this particular exception just use throw new RuntimeException("Put message here");

Remember that Runtime Exceptions are unchecked

answered Sep 11 '17 at 10:20

jpuriol

362
2
14

explicitedly says he does not want new exception type yet you suggest for him to make custom exception? – Enerccio Sep 11 '17 at 10:21
1

I'm countering the downvote on the grounds that creating a custom exception may actually be the most prudent thing to do here. – Tim Biegeleisen Sep 11 '17 at 10:32
1

while that is true, it does not answer the question – Enerccio Sep 11 '17 at 10:37
throw new RuntimeException("Put message here"); worked thank you – deepti mullur Sep 12 '17 at 06:19

score 0 · Answer 2 · answered Sep 11 '17 at 10:15

0

Why would you not want to create a custom exception yourself?

Anyhow, I'd go for the UnsupportedOperationException in this case.

answered Sep 11 '17 at 10:15

Marc Van Deuren

121
1
9

score 0 · Answer 3 · answered Sep 11 '17 at 10:25

0

The only possible way without new type is to create normal exception (Exception or RuntimeException, both support string message), passing some specific message of your choice and then in later code checking against Exception or RuntimeException and matching your message.

try {
    throw new Exception("my specific string message");
catch (Exception e) {
    if ("my specific string message".equals(e.getMessage()) {
        // your code
    else {
        throw e;
    }
}

potential drawback is that now you have to declare exception if it is Exception. Solutions are to use RuntimeException or Unsafe.throwException()

answered Sep 11 '17 at 10:25

Enerccio

257
1
10
23

I tried above solution, it doesn't throw an exception if you are calling the method from other class. In-fact e.getMessage() is null. – deepti mullur Sep 11 '17 at 10:49
message is something you should set yourself as an identifier tag – Enerccio Sep 11 '17 at 11:15
Obviously, I did set a message but its still null. – deepti mullur Sep 11 '17 at 13:09

Is there any custom exception already in library which we can use where ever we want it to throw with custom message?

3 Answers3