UsbInterface null for except 1 device

Question

This way I found solution to recognize if the connected device is storage device.

I am following this thesis to understand how the USB Communication with Storage device is done. But the main problem I faced is that For all the connected device except the last connected device I am not getting the UsbInterface and so the related UsbEndPoints. Now How can I recognize all other connected storage device.

When 3 devices are connected the log I got is:

found usb device: UsbDevice[
                mName=/dev/bus/usb/001/009,
                mVendorId=1423,
                mProductId=25479,
                mClass=0,
                mSubclass=0,
                mProtocol=0,
                mManufacturerName=Generic,
                mProductName=Mass Storage,
                mSerialNumber=EE44CC66,
                mConfigurations=[UsbConfiguration[mId=1,mName=null,mAttributes=128,mMaxPower=100,
                        mInterfaces=[
                            UsbInterface[mId=0,mAlternateSetting=0,mName=null,mClass=8,mSubclass=6,mProtocol=80,
                            mEndpoints=[
                                UsbEndpoint[mAddress=1,mAttributes=2,mMaxPacketSize=512,mInterval=0]
                                                    UsbEndpoint[mAddress=130,mAttributes=2,mMaxPacketSize=512,mInterval=0]
                                ]
                            ]
            ]

found usb device: UsbDevice[
                mName=/dev/bus/usb/001/003,
                mVendorId=3141,
                mProductId=21236,
                mClass=0,
                mSubclass=0,
                mProtocol=0,
                mManufacturerName=AliTV Remote V1,
                mProductName=Airmouse,
                mSerialNumber=null,
                mConfigurations=[UsbConfiguration[mId=1,mName=null,mAttributes=160,mMaxPower=50,
                            mInterfaces=[]
                ]

found usb device: UsbDevice[
            mName=/dev/bus/usb/001/007,
            mVendorId=1423,
            mProductId=25479,
            mClass=0,
            mSubclass=0,
            mProtocol=0,
            mManufacturerName=Generic,
            mProductName=Mass Storage,
            mSerialNumber=94012721,
            mConfigurations=[UsbConfiguration[mId=1,mName=null,mAttributes=128,mMaxPower=100,
                        mInterfaces=[]
            ]

Abridgment