In Java, byte arrays are often used to transmit raw binary data and character encoded data. An attempt to read raw binary data as if it were character encoded data fails because some of the bytes may not represent valid characters in the default or specified encoding scheme. For instance, a cryptographic key containing non-representable bytes may be required to be converted to character encoded data for its suitable transmission. However, this may produce errorneous results.
Also, see FIO02-J. Keep track of bytes read and account for character encoding while reading data and FIO03-J. Specify the character encoding while performing file or network IO.
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