Core Java Interview Questions and Answers
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Ques 231. What is inner class?
If the methods of the inner class can only be accessed via the instance of the inner class, then it is called inner class.
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Ques 232. What is the use of serializable?
To persist the state of an object into any perminant storage device.
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Ques 233. Why do threads block on I/O?
Threads block on i/o (that is enters the waiting state) so that other threads may execute while the I/O operation is performed.
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Ques 234. What class allows you to read objects directly from a stream?
The ObjectInputStream class supports the reading of objects from input streams.
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Ques 235. What an I/O filter?
An I/O filter is an object that reads from one stream and writes to another, usually altering the data in some way as it is passed from one stream to another.
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