[SOLVED] Handle own exception

[stevemcc]

I have an assignment to make my own exception. The exception need to be thrown when the user enters a string longer than 31 characters. Then next, task and the one I am struggling with is to do the same, but this time correctly handle the exception gracefully.

StringTooLongException.java

Code:

public class StringTooLongException extends Exception {
	
	public StringTooLongException(String message) {
		super(message);
	}
	
}

TooLongCrashes.java

Code:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class TooLongCrashes {

	public static void main(String[] args) throws StringTooLongException, IOException {
		BufferedReader stdin = new BufferedReader(new InputStreamReader(System.in));
	    String message;
		boolean c = true;
		while(c) {
			stdin = new BufferedReader(new InputStreamReader(System.in));
			message = stdin.readLine();
			if(message.length() >= 32)
				throw (new StringTooLongException(message));
			else
				System.out.println(message);
			
		}

	}

}

TooLogHandled.java

Code:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class TooLongHandled {

	static TooLongCrashes too;
		
	public static void main(String[] args) throws StringTooLongException, IOException {
		try {
		too = new TooLongCrashes();
		} catch(Exception e) {
			System.out.println(too.toString());
		}
	}
}

In TooLongHandled.java I cannot seem to figure out how I should go about handling the exception.

[Eranga]

Seems to me this is work. Where you stuck with.

[CaptainMorgan]

Hi steve. All you need to do is:

Code:

public class StringTooLongException extends Exception {
    
    public StringTooLongException(String message) {
        throw new IllegalArgumentException("Exception: String too long.");
    }
    
}

With this, the output is below on an input of "Hello":

Quote:

Hello
Hello

But on input longer than 32 you see this:

Quote:

123456789012345678901234567890123
Exception in thread "main" java.lang.IllegalArgumentException: Exception: String too long.
at StringTooLongException.<init>(StringTooLongExcepti on.java:4)
at TooLongCrashes.main(TooLongCrashes.java:17)
Java Result: 1

Should this satisfy your question, please mark this thread as 'Solved', if not, definitely let us assist with more on this topic.

My bad.. I didn't see that it actually worked before I made an adjustment.. so, basically you picked up another way to throw an exception.

[Eranga]

Steve may be worried, on his code with the exception just the user input string is displayed. May be looking to make much descriptive exception message as Captain says.