Android Host API: read and write operations (asynchronous)

readAndWrite

/**
     * Gets the response from the connected device.
     * @param outRequest UsbRequest referencing the request.
     * @return Returns the response in a byte[].
     * @throws UsbException
     */
    public byte[] read(UsbRequest outRequest) throws UsbException {
        if (mUsbDeviceConnection == null) {
            throw new UsbException("no connection available");
        }

        ByteBuffer buffer = ByteBuffer.allocate(MAX_PACKAGE_SIZE);

        // Receive data from device
        if (outRequest.equals(mUsbDeviceConnection.requestWait())) {
            UsbRequest inRequest = new UsbRequest();
            inRequest.initialize(mUsbDeviceConnection, epIN);
            if (inRequest.queue(buffer, MAX_PACKAGE_SIZE)) {
                mUsbDeviceConnection.requestWait();
                return buffer.array();
            }
        }
        return null;
    }

    /**
     * Write a command to the connected device.
     * @param command Byte[] containing the opcode for the command.
     * @return Returns the response in a byte[].
     * @throws UsbException
     */
    public UsbRequest write(byte[] command) throws UsbException {
        if (mUsbDeviceConnection == null) {
            throw new UsbException("no connection available");
        }

        ByteBuffer buffer = ByteBuffer.allocate(MAX_PACKAGE_SIZE);

        UsbRequest outRequest = new UsbRequest();
        outRequest.initialize(mUsbDeviceConnection, epOUT);

        buffer.put(command);
        outRequest.queue(buffer, MAX_PACKAGE_SIZE);

        return outRequest;
    }