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The read() methods return as soon as they find available input data. As a result, the read() method these methods can stop reading data before the array is filled, because there might not be enough data available to fill the array.
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This rule applies only to read() methods that take an array argument. To read a single byte, use the an InputStream.read() method that takes no arguments and returns an int. To read a single character, use a Reader.read() method that takes no arguments and returns the character read as an int.
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