Buffered input stream implements FilterInputStream and provides for buffered reads.
By default, BufferedInputStream's buffer size is set at 4 kilobytes.
To create a buffered input stream, use BufferedInputStream, or BufferedInputStream.sized to specify the buffer's size at construction.
To get the size of a buffer within a buffered input stream, use get_buffer_size. To change the size of a buffered input stream's buffer, use set_buffer_size. Note that the buffer's size cannot be reduced below the size of the data within the buffer.