Summary: Constants | Methods | Inherited Methods

HidDevice

Kotlin |Java

public final class HidDevice
extends Object implements AutoCloseable

java.lang.Object
↳	android.hardware.hid.HidDevice

Represents a Human Interface Device (HID) connected to the system.

HIDs are devices like keyboards, mice, game controllers, and other peripherals that follow the HID specification for communication over various transports (USB, Bluetooth, etc.).

Summary

Constants
`int`	`TRANSPORT_BLUETOOTH` Transport type is Bluetooth.
`int`	`TRANSPORT_I2C` Transport type is I2C.
`int`	`TRANSPORT_SPI` Transport type is SPI.
`int`	`TRANSPORT_UNKNOWN` Transport type is unknown.
`int`	`TRANSPORT_USB` Transport type is USB.
`int`	`TRANSPORT_VIRTUAL` Transport type is Virtual.

Public methods
`void`	`close()` Releases all system resources and closes the connection to the HID device.
`boolean`	`equals(Object o)` Indicates whether some other object is "equal to" this one.
`void`	`getFeatureReport(int reportId, Executor executor, OutcomeReceiver<Report, Exception> callback)` Get a feature report from the HID device.
`String`	`getName()` The human-readable name of the HID device.
`String`	`getPhysicalAddress()` The physical address of the device, representing its connection path through the system's device tree (e.g., the USB hub and port path).
`int`	`getProductId()` The product ID for this device.
`byte[]`	`getReportDescriptor()` The raw HID report descriptor for the device.
`int`	`getTransport()` The transport type used by this device.
`String`	`getUniqueId()` A unique identifier for this device instance.
`int`	`getVendorId()` The vendor ID for this device.
`int`	`hashCode()` Returns a hash code value for the object.
`boolean`	`isOpen()` Returns whether the HID device is currently open and ready for communication.
`void`	`open(Executor executor, OutcomeReceiver<HidDevice, Exception> callback)` Opens the HID device so that it can be used to send and receive HID reports.
`void`	`sendFeatureReport(Report report, Executor executor, OutcomeReceiver<Void, Exception> callback)` Send a feature report to the HID device.
`void`	`sendOutputReport(Report report, Executor executor, OutcomeReceiver<Void, Exception> callback)` Send an output report to the HID device.
`String`	`toString()` Returns a string representation of the object.

Inherited methods

From class


        
          java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

From interface


        
          java.lang.AutoCloseable


      close()

Closes this resource, relinquishing any underlying resources.

Constants

TRANSPORT_BLUETOOTH

public static final int TRANSPORT_BLUETOOTH

Transport type is Bluetooth.

Constant Value: 5 (0x00000005)

TRANSPORT_I2C

public static final int TRANSPORT_I2C

Transport type is I2C.

Constant Value: 24 (0x00000018)

TRANSPORT_SPI

public static final int TRANSPORT_SPI

Transport type is SPI.

Constant Value: 28 (0x0000001c)

TRANSPORT_UNKNOWN

public static final int TRANSPORT_UNKNOWN

Transport type is unknown.

Constant Value: 0 (0x00000000)

TRANSPORT_USB

public static final int TRANSPORT_USB

Transport type is USB.

Constant Value: 3 (0x00000003)

TRANSPORT_VIRTUAL

public static final int TRANSPORT_VIRTUAL

Transport type is Virtual.

Constant Value: 6 (0x00000006)

Public methods

close

public void close ()

Releases all system resources and closes the connection to the HID device.

This method is synchronous and idempotent; calling it on an already closed device has no effect.
Requires Manifest.permission.ACCESS_HID

equals

public boolean equals (Object o)

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

It is reflexive: for any non-null reference value x, x.equals(x) should return true.
It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
`o`	`Object`: This value may be `null`.

Returns
`boolean`	`true` if this object is the same as the obj argument; `false` otherwise.

getFeatureReport

public void getFeatureReport (int reportId, 
                Executor executor, 
                OutcomeReceiver<Report, Exception> callback)

Get a feature report from the HID device.

The device must be opened first before calling this method.

On success, callback.onResult is called with the retrieved Report. On failure, callback.onError is called with one of the following:

IOException: If the underlying hardware device could not be accessed or the system service returned a failure.
SecurityException: If the caller lacks the required permission.

.
Requires Manifest.permission.ACCESS_HID

Parameters
`reportId`	`int`: the feature report to get.
`executor`	`Executor`: the executor on which the callback will be invoked. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`callback`	`OutcomeReceiver`: the callback object to be used to notify of the report or an error. This value cannot be `null`.

Throws
`IllegalStateException`	if the device is not open.

getName

public String getName ()

The human-readable name of the HID device.

Returns
`String`	This value cannot be `null`.

getPhysicalAddress

public String getPhysicalAddress ()

The physical address of the device, representing its connection path through the system's device tree (e.g., the USB hub and port path).

This value is unique to the device's physical connection point on the current system.

Returns
`String`	This value cannot be `null`.

getProductId

public int getProductId ()

The product ID for this device.

A product ID uniquely identifies which product within the address space of a given vendor, identified by the device's vendor ID. A value of 0 will be assigned where a product ID is not available.

Returns
`int`

getReportDescriptor

public byte[] getReportDescriptor ()

The raw HID report descriptor for the device.

This descriptor defines the format and meaning of the reports sent and received by the device, following the HID specification.

Returns
`byte[]`	This value cannot be `null`.

getTransport

public int getTransport ()

The transport type used by this device.

Returns
`int`	Value is one of the following: `TRANSPORT_UNKNOWN` `TRANSPORT_USB` `TRANSPORT_BLUETOOTH` `TRANSPORT_SPI` `TRANSPORT_I2C` `TRANSPORT_VIRTUAL`

getUniqueId

public String getUniqueId ()

A unique identifier for this device instance.

This value is typically the device's serial number if available, or a system-generated unique ID. This ID is unique among all currently connected HID devices.

Returns
`String`	This value cannot be `null`.

getVendorId

public int getVendorId ()

The vendor ID for this device.

A vendor ID uniquely identifies the company who manufactured the device. A value of 0 will be assigned where a vendor ID is not available.

Returns
`int`

hashCode

public int hashCode ()

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

The general contract of hashCode is:

Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

Returns
`int`	a hash code value for this object.

isOpen

public boolean isOpen ()

Returns whether the HID device is currently open and ready for communication.

Note: This method returns false while the device is in the process of opening. It only returns true after the open(Executor, OutcomeReceiver) operation has successfully completed.

Returns
`boolean`	`true` if the device is fully opened; `false` otherwise.

open

public void open (Executor executor, 
                OutcomeReceiver<HidDevice, Exception> callback)

Opens the HID device so that it can be used to send and receive HID reports.

This is an asynchronous operation. If an open operation is already in progress, the provided callback is queued and will be notified once the underlying operation completes. The state transitions are as follows:

If the device is already opened, callback.onResult is invoked immediately.
If the device is currently opening, the request is queued and callback will be notified when the existing operation finishes.
If the device is closed, it transitions to an opening state and attempts to establish a connection via the system service.

On success, callback.onResult is called with this HidDevice instance. On failure, callback.onError is called with one of the following:

IOException: If the underlying hardware device (e.g., hidraw node) could not be accessed or the system service returned a failure.
SecurityException: If the caller lacks the required permission, or the user has rejected access to the device.
RemoteException: If the HID system service is unreachable.

.
Requires Manifest.permission.ACCESS_HID

Parameters
`executor`	`Executor`: The executor on which the callback will be invoked. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`callback`	`OutcomeReceiver`: The object to be notified of success or failure. This value cannot be `null`.

sendFeatureReport

public void sendFeatureReport (Report report, 
                Executor executor, 
                OutcomeReceiver<Void, Exception> callback)

Send a feature report to the HID device.

The device must be opened first before calling this method.

On success, callback.onResult is called with null. On failure, callback.onError is called with one of the following:

IOException: If the underlying hardware device could not be accessed or the system service returned a failure.
SecurityException: If the caller lacks the required permission.

.
Requires Manifest.permission.ACCESS_HID

Parameters
`report`	`Report`: the feature report to send. This value cannot be `null`.
`executor`	`Executor`: the executor on which the callback will be invoked. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`callback`	`OutcomeReceiver`: the callback object to be used to notify of an error. This value cannot be `null`.

Throws
`IllegalStateException`	if the device is not open.

sendOutputReport

public void sendOutputReport (Report report, 
                Executor executor, 
                OutcomeReceiver<Void, Exception> callback)

Send an output report to the HID device.

The device must be opened first before calling this method.

On success, callback.onResult is called with null. On failure, callback.onError is called with one of the following:

IOException: If the underlying hardware device could not be accessed or the system service returned a failure.
SecurityException: If the caller lacks the required permission.

.
Requires Manifest.permission.ACCESS_HID

Parameters
`report`	`Report`: the output report to send. This value cannot be `null`.
`executor`	`Executor`: the executor on which the callback will be invoked. This value cannot be `null`. Callback and listener events are dispatched through this `Executor`, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use `Context.getMainExecutor()`. Otherwise, provide an `Executor` that dispatches to an appropriate thread.
`callback`	`OutcomeReceiver`: the callback object to be used to notify of an error. This value cannot be `null`.

Throws
`IllegalStateException`	if the device is not open.

toString

public String toString ()

Returns a string representation of the object.

Returns
`String`	a string representation of the object.