Help me in java coding

I had just started learning java and i totally have no experience in programming before.

So my lecturer asked the whole class to create a coding to detect identifier problems.

The question is:

Create a coding by asking user to input random letters and etc.

If the there is no identifier error the output will print out " Successful data input" and vice versa "The data contains identifier error".

My lecturer said its a simple coding but i still can't figure it out. So somebody please help me and do make it simple because i had only learned till buffreader.

By the way im using texpad.

Thanks in advance and hope the problem will settle asap.

Break the program into simple steps and do them one at a time.
First step:
ask the user a question and get his response.
Then print out his response.

Look at the Scanner class for ways to read the input.

I only want to know how to detect the errors of the identifier so that i can create the coding and the produce the "The data contains identifier error".

I only manage to get to the successful data input. But when i input random letters that contains # it still comes out as successful. So i want to know how to detect the identifier error in the coding.

Quote:

---

I only want to know how to detect the errors of the identifier

---

To do that you need to define the "syntax" for a valid identifier.
Do you have that? What is a valid identifier?

example if i input : #alslsl

It would print invalid as it cannot start with the # symbol, % symbol and numbers.

To write the code, you need a definition of what the code is to do.
Can you define what a valid identifier is?
Or what an invalid identifier is? Examples are not good enough, unless you can list ALL of the millions of bad identifiers.

Something like this: The first character must be an uppercase letter from A-K, followed by 2 or more numeric digits in the range 4-7 followed by 1 lower case letter in the range: k-m. For example: H445m is valid. H4k is not valid.