char[] buf = new char[DEFAULT_BUF_SIZE];
    int nRead;
    long total = 0;
    while ((nRead = from.read(buf)) != -1) {
      to.write(buf, 0, nRead);
      total += nRead;
    }
    return total;
  }

  /**
   * Reads all characters from a {@link Readable} object into a {@link String}. Does not close the
   * {@code Readable}.
   *
   * @param r the object to read from

}

var errUnreadByte = errors.New("bytes.Buffer: UnreadByte: previous operation was not a successful read")

// UnreadByte unreads the last byte returned by the most recent successful
// read operation that read at least one byte. If a write has happened since
// the last read, if the last read returned an error, or if the read read zero
// bytes, UnreadByte returns an error.
func (b *Buffer) UnreadByte() error {

    }

    /**
     * Reads bytes from the file into the specified byte array.
     *
     * @param b the byte array to read data into
     * @return the number of bytes read, or -1 if end of file is reached
     * @throws SmbException if an I/O error occurs
     */
    public int read(final byte b[]) throws SmbException {
        return read(b, 0, b.length);
    }

    /**

      }
    }

    override fun read(
      sink: Buffer,
      byteCount: Long,
    ): Long {
      require(byteCount >= 0L) { "byteCount < 0: $byteCount" }
      check(!closed) { "closed" }
      if (bytesRemaining == 0L) return -1

      val read = super.read(sink, minOf(bytesRemaining, byteCount))
      if (read == -1L) {

    byte[] buf = createBuffer();
    int read;
    do {
      read = input.read(buf);
    } while (read != -1 && processor.processBytes(buf, 0, read));
    return processor.getResult();
  }

  /**
   * Reads some bytes from an input stream and stores them into the buffer array {@code b}. This
   * method blocks until {@code len} bytes of input data have been read into the array, or end of

        // Read first message
        assertEquals(1, sis.read());
        assertEquals(2, sis.read());

        // Read second message
        assertEquals(3, sis.read());
        assertEquals(4, sis.read());
        assertEquals(5, sis.read());

        // After all data is consumed, next read throws IOException
        assertThrows(IOException.class, () -> sis.read());
    }

    @Test

     */

    @Override
    public int read(final byte[] b, final int off, final int len) throws IOException {
        return readDirect(b, off, len);
    }

    /**
     * Reads up to len bytes of data from this input stream into an array of bytes.
     * Optimized for better performance with larger read sizes and reduced round trips.
     *
     * @param b the buffer to read into

        sourcePos += bytesToRead
        return bytesToRead
      }

      // Read from upstream. This always reads a full buffer: that might be more than what the
      // current call to Source.read() has requested.
      try {
        val upstreamBytesRead = upstream!!.read(upstreamBuffer, bufferMaxSize)

        // If we've exhausted upstream, we're done.

		Method: Deflate,
		Mode:   0755 | fs.ModeDevice | fs.ModeCharDevice,
	},
}

func TestWriter(t *testing.T) {
	largeData := make([]byte, 1<<17)
	if _, err := rand.Read(largeData); err != nil {
		t.Fatal("rand.Read failed:", err)
	}
	writeTests[1].Data = largeData
	defer func() {
		writeTests[1].Data = nil
	}()

	// write a zip file
	buf := new(bytes.Buffer)
	w := NewWriter(buf)

            // Simple mock implementation
            byte[] temp = new byte[length];
            int read = in.read(temp, 0, length);
            if (read < length) {
                throw new IOException("Incomplete trailer data");
            }
            trailerBytesRead = read;
            return read;
        }
    }