Get drive letters of USB 3.0 devices (Java under Windows)

860 views Asked by At

My Java program needs to get a list of the drive letters of connected USB devices, but only those that support USB 3.0 (both the device and the USB port it is plugged into, so that it works with high speed).

Currently I try to use WMI through a PowerShell command my Java programm executes.

I already found this: Powershell: Grab USB Drive letter. But it would also list USB 2.0 devices.

Regarding version detection I found this: How to check the version of the available USB ports? - The PowerShell command I tried is Get-WmiObject Win32_USBHub. This brings up several problems. First: It lists far more stuff than only USB drives (I think also all the USB hubs of my PC). Second: Even though there is a field USBVersion for all items in the list it is always empty.

Update

The essence of my research over the last days is, that there are 2 realms of information I need to connect.

  • Drives / Logical Drives
    • Drive Letter
    • BusType (is equal to "USB" for my matter)
  • USB devices
    • Vendor ID and Product ID (VID&PID)
    • bcdUSB (value within the usb device descriptor, indicating USB Version)

For a given drive letter I need to find the bcdUSB value. But I haven't found a way to get the drive corresponding to a USB device.

What I tried so far

WMI over PowerShell

Relevant commands I found are

Get-Disk               // Get BusType
gwmi Win32_LogicalDisk // Get drive letter
// Those make the connection between disk and logical disk
gwmi Win32_LogicalDiskToPartition
gwmi Win32_LogicalDiskToPartition

Even though I get the BusType I couldn't make a connection to bcdUSB

usb4java (Link)

I only get information from the USB device realm here. I can load devices and see ther VID&PID and the bcdUSB value, but no way to map this to drives and drive letters.

lsusb via Cygwin

According to this post the linux command is easier to handle than WMI. So I tried to use it under Windows. But I like usb4java I only got VID&PID + bcdUSB, not the mount point (drive letter).

Searching the Windows Registry

I did a few string searchs in the Windows registry. No success.

Reading Windows Event log

I thought about ovserving Windows events to detect what Drive and what USB device connect at the same time. I didn't even find events when plugging in a USB stick.

2

There are 2 answers

0
chrisphl On BEST ANSWER

Maybe this is what you are looking for: Find Windows Drive Letter of a removable disk from USB VID/PID At least someone marked the answer as working... :-)

0
Ruik On

Since the suggested Link solves this problem for C# not Java and leaves out one step, I'll post my final code here.

Summary

In Java

  • Use USB4Java to find all connected USB devices with bcdUSB=0x0300
  • Get Vendor ID and Product ID (VID&PID) for that devices

Via Powershell (with jPowerShell)

  • Get PnPEntity for given VID&PID
  • Get related USB Controller
  • Find associator of that USB Controller that is associated with a disk drive
  • Get that Disk drive
  • Get related disk partition
  • Get related logical disk -> LogicalDisk.DeviceID = Drive Letter

Code

Java class:

class UsbDetector {

  private PowerShell shell;

  @PostConstruct
  private void init() {
    shell = com.profesorfalken.jpowershell.PowerShell.openSession();
  }

  @OnDestroy
  private void onShutdownHook() {
    shell.close();
  }

  /**
   * Get drive letters of USB 3.0 devices.
   */
  public List<String> getDriveLettersForUsb3Devices() throws IOException, UsbException {
    List<UsbDevice> devicesUSB3 = getAllUsb3Devices();

    ImmutableList.Builder<String> driveLetterList = ImmutableList.builder();
    for (UsbDevice device : devicesUSB3) {
      String vidAndPid = getVidAndPid(device);

      String powerShellScript = buildScript(vidAndPid);

      String driveLetter = executeOnPowerShell(powerShellScript);
      driveLetterList.add(driveLetter);
    }

    return driveLetterList.build();
  }

  private String executeOnPowerShell(String powerShellScript) {
    InputStream psScriptStream = new ByteArrayInputStream(powerShellScript.getBytes());
    BufferedReader psScriptReader = new BufferedReader(new InputStreamReader(psScriptStream));

    PowerShellResponse response = shell.executeScript(psScriptReader);

    return response.getCommandOutput();
  }

  private String buildScript(String vidAndPid) throws IOException {
    InputStream psScriptStream =
        getClass().getClassLoader().getResourceAsStream("GetUsbDrives.ps1");

    String psScript = IOUtil.toString(psScriptStream);

    psScript = String.format("$input=\"%s\"", vidAndPid) + "\n" + psScript;
    return psScript;
  }

  /**
   * The Vendor ID and Product ID are necessary to find the device via WMI.
   */
  private String getVidAndPid(UsbDevice device) {
    short vendorId = device.getUsbDeviceDescriptor().idVendor();
    short productId = device.getUsbDeviceDescriptor().idProduct();

    String vendorIdHexString = String.format("%04x", vendorId).toUpperCase();
    String productIdHexString = String.format("%04x", productId).toUpperCase();

    String vidAndPid = String.format("VID_%s&PID_%s", vendorIdHexString, productIdHexString);
    return vidAndPid;
  }

  /**
   * From all Usb devices find those with USB 3.0. The value bcdUsb is a hexadecimal coded number
   * telling us the USB version.
   */
  private List<UsbDevice> getAllUsb3Devices() throws UsbException {
    List<UsbDevice> devicesUSB3 = Lists.newArrayList();
    UsbServices services = new org.usb4java.javax.Services();

    UsbHub hub = services.getRootUsbHub();
    List<UsbDevice> devices = getAllUsbDevices(hub);
    for (UsbDevice device : devices) {
      UsbDeviceDescriptor descriptor = device.getUsbDeviceDescriptor();
      short bcdUsb = descriptor.bcdUSB();
      String bcdDecoded = DescriptorUtils.decodeBCD(bcdUsb);

      if (Objects.equal(bcdDecoded, "3.00")) {
        devicesUSB3.add(device);
      }
    }
    return devicesUSB3;
  }

  /**
   * UsbHubs can either mount UsbDevices or further UsbHubs. This method searches through the tree
   * of UsbHubs for UsbDevices and returns them as list.
   */
  private List<UsbDevice> getAllUsbDevices(UsbHub hub) {
    List<UsbDevice> devices = Lists.newArrayList();

    List<UsbDevice> attachedDevices = hub.getAttachedUsbDevices();
    for (UsbDevice device : attachedDevices) {
      if (device instanceof UsbHub) {
        List<UsbDevice> subdevices = getAllUsbDevices((UsbHub) device);
        devices.addAll(subdevices);
      } else {
        devices.add(device);
      }
    }
    return devices;
  }

}

PowerShell script:

# $input = "VID_XXXX&PID_XXXX (this line is added in Java Code)

# For given VID and PID of a USB device we search for 
# the corresponding logical disk to get the drive letter.

# The chain of objects is:
# PnPEntity (PnP = Plug and Play)
# -> USBController
# -> Some associator of USBController that has a related disk drive
# -> diskDrive
# -> diskPartition
# -> logicalDisk  

# Find PnPEntity for given VID and PID
$usbPnPEntity = (gwmi Win32_PnPEntity | where DeviceID -match $input)

# Get USB Controller related to PnP Entity
$usbController = $usbPnPEntity.getRelated("Win32_USBController") 
$usbControllerID = $usbController.DeviceID

# Find objects associated with the USB Controller
$query = "ASSOCIATORS OF {Win32_USBController.DeviceID='$usbControllerID'}"
$associators = ([wmisearcher]$query).get()

# Search through associators
foreach ($associator in $associators) {
    # Find associator that is related to a disk Drive
    $assoDeviceID = $associator.DeviceID
    $diskDrive = (gwmi win32_diskdrive | where PNPDeviceID -eq $assoDeviceID)
    
    if($diskDrive){
        # Get logical Disk related to the disk drive
        $logicalDisk = $diskDrive.getRelated("Win32_DiskPartition").getRelated("Win32_LogicalDisk")
        
        # Print device ID which is the drive letter (e.g. "C:")
        $logicalDisk.DeviceID
        break
    }

}

Maven dependencies:

    <dependency>
        <groupId>org.usb4java</groupId>
        <artifactId>usb4java-javax</artifactId>
        <version>1.3.0</version>
    </dependency>
    <dependency>
        <groupId>com.profesorfalken</groupId>
        <artifactId>jPowerShell</artifactId>
        <version>3.1.1</version>
    </dependency>