Subclassing Exceptions in Java

Custom Exceptions:

• Java allows you to create your own exceptions, in addition to internal exceptions, to handle application-specific errors.
• To create a custom exception, simply define a subclass of Exception, which is a subclass of Throwable.

Simple Deployment:

• Custom exceptions do not need additional methods to be valid; the creation of a new class already allows its use in error handling.
• The Exception class inherits methods from the Throwable class, which can be used or overridden as needed.

Custom Exception Example:

• The NonIntResultException exception is created to be thrown when dividing two integers results in a non-integer value.
• The class contains two fields (n and d) to store the values ​​that caused the error, as well as a constructor to initialize them.
• The toString() method is overridden to provide a detailed description of the exception.

Example Code:
An array number and another denom contain values ​​that will be divided.
In the loop, it checks whether the value in number is odd, and if so, it throws a NonIntResultException.

Try-catch blocks are used to catch and handle exceptions:

• ArithmeticException: catches division by zero.
• ArrayIndexOutOfBoundsException: captures index outside the bounds of the array.
• NonIntResultException: catches divisions that result in fractional values.

Program Exit:

• Displays the division result if it is valid.
• Displays error messages depending on the type of exception:
• "Can't divide by Zero!" for divisions by zero.
• "No matching elements found." for indexes outside the array.
• "Result of [n] / [d] is non-integer." for divisions that do not result in integers.

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