android usb通信

public class USBConnectionManager {
   private UsbManager manager;
   private UsbDevice mUsbDevice;
   private UsbInterface mInterface;
   private UsbEndpoint usbEpOut;

   private UsbEndpoint usbEpIn;
   private UsbDeviceConnection mDeviceConnection;
   private final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
   private OnUSBInitListener mOnUSBInitListener;

   public USBConnectionManager(Context context, int vID, int pID, OnUSBInitListener onUSBInitListener) {
      this.mOnUSBInitListener = onUSBInitListener;
      manager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
      HashMap<String, UsbDevice> deviceList = manager.getDeviceList();
      Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
      while (deviceIterator.hasNext()) {
         UsbDevice device = deviceIterator.next();
         if (device.getVendorId() == vID && device.getProductId() == pID) {
            mUsbDevice = device;
            break;
         }
      }
      if (mUsbDevice != null) {
         mInterface = mUsbDevice.getInterface(0);
         if (mInterface != null) {
            if (mInterface.getEndpoint(0) != null) {
               usbEpIn = mInterface.getEndpoint(0);