Reads into an array of bytes. This method will
block until some input is available.
Returns:
the actual number of bytes read, -1 is
returned when the end of the stream is reached.
Parameters:
-
b - the buffer into which the data is read
-
off - the start offset of the data
-
len - the maximum number of bytes read
Throws:
-
IOException - If an I/O error has occurred.