writing Custom exception and its implementation

[vinsun]

Hi all,

can somebody help me writing a custom exception class
checkDateException and also how to use that class in PatientDateVerifier where the
scenario goes like this.............


Class: CheckDateException
Description: This class is a checked exception class.


Constructor: public CheckDateException(GregorianCalendar checkDate,
String msg)
Description: Saves checkDate and msg to the class’ instance
variables.


Method: public String toString()
Description: Concatenates the String value of checkDate and msg.


Class: PatientDateVerifier
Description: This class will be used to verify a patient’s checkup
date.


Constructor: public PatientDateVerifier()
Description: Creates an instance of the DateValidator class.


Method: public void verifyCheckUpDate(GregorianCalendar checkUpDate)
throws CheckDateException
Description: If checkUpDate is a future date, it throws an exception
with the
message: Remarks:\nInvalid date: Check-up date is in the future.


If checkUpDate is older than six months, it throws an exception
with the message: Remarks:\nCheck-up date is longer than six
months.\nPatient needs another checkup.


If checkUpDate falls in the month of December, it throws an
exception with the message: Remarks:\nPatient needs smallpox
vaccination.


Any help or suggestion is appreciated.


Thanks and regards

[JosAH]

Hi all,

can somebody help me writing a custom exception class
checkDateException and also how to use that class in PatientDateVerifier

Writing another checked exception is easy: extend your class from the Exception class; may I sugges you create a general class from which you can extend other, more specific exceptions? Like so:

public class YourAppException extends Exception {
	
	public YourAppException() {
		super();
	}

	public YourAppException(String msg) {
		super(msg);
	}

	public YourAppException(Throwable t) {
		super(t);
	}

	public YourAppException(String msg, Throwable t) {
		super(msg, t);
	}
}

Your checkDateException (a bad name b.t.w.) can be a subclass of the class mentioned above. By extending from the Exception class the excpeptions are checked by the compiler.

kind regards,

Jos