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Q) What is the need of user defined exceptions?




A)
->when some part of the application is requesting the other part of the application, the other part is unable to perform the requested operation either because of data not available or this situation rule of the application is violated. This situation is not available of runtime environment rule.
->JVM doesn’t throw the exception. Then, the other part of the application should intimate to the first part of the application that something abnormal occurred as per application rules. To represent application specify abnormally, user defined exception are used.
->in a real time java project to pass an exception from one layer to other layer in technology independent manner and there by promoting loose coupling between layers, user defined exceptions are used.

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