If a finally clause is specified, irrespective of whether the try or catch block executes to completion or not, the finally block is executed. Consequently, statements that cause the finally block to terminate abruptly may can mask of any thrown exceptions. ConsequentlyHence, keywords like return, break, continue and throw should never be used within a finally block.
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Here, the finally block completes abruptly because a return statement occurs within it. As a result, when the IllegalStateException is thrown, it does not propagate all the way up through the call stack. This is because of the abrupt termination of the finally block that suppresses any useful exception information from being displayed by overriding the exception thrown in the try block with its own message. Note that even if the try block returns some value, the finally block is executed.
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