Exception handling : throw, throws and Throwable

java exception-handling throw throws throwable
Sumithra picture Sumithra · Oct 15, 2010 · Viewed 54.8k times · Source

Can any of you explain what the differences are between throw, throws and Throwable and when to use which?

Answer

aioobe picture aioobe · Oct 15, 2010

  • throws : Used when writing methods, to declare that the method in question throws the specified (checked) exception.

    As opposed to checked exceptions, runtime exceptions (NullPointerExceptions etc) may be thrown without having the method declare throws NullPointerException.

  • throw: Instruction to actually throw the exception. (Or more specifically, the Throwable).

    The throw keyword is followed by a reference to a Throwable (usually an exception).

Example:

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  • Throwable: A class which you must extend in order to create your own, custom, throwable.

Example:

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