How to create an InvalidLineNumberException class in java with a constructor and methods

Answer 1

public class InvalidLineNumberException extends Exception {
private int lineNumber;

public InvalidLineNumberException(int lineNumber) {
super("Invalid line number: " + lineNumber);
this.lineNumber = lineNumber;
}

public int getLineNumber() {
return lineNumber;
}
}

This class extends the Exception class, which is the base class for exceptions in Java. It has a constructor that takes an int argument representing the invalid line number, and a method getLineNumber() that returns the invalid line number.

The constructor uses the super keyword to call the constructor of the base Exception class, passing in a message containing the invalid line number. It then saves the line number in an instance variable so that it can be accessed later.

Answer 2

To use this class, you can throw an InvalidLineNumberException when you encounter an invalid line number in your code, and catch it to handle the error appropriately.

For example:
try {
// some code that might throw InvalidLineNumberException
} catch (InvalidLineNumberException ex) {
System.out.println("Invalid line number: " + ex.getLineNumber());
}

Note that the InvalidLineNumberException class is a checked exception, which means that any method that throws it must either catch it or declare it in the method's throws clause. This is because checked exceptions indicate a potential problem that must be handled by the caller of the method.

Answer 3

Check out the below link, It might help you.

https://www.javatpoint.com/exception-class-in-java