UsbDevice
public
class
UsbDevice
extends Object
implements
Parcelable
java.lang.Object | |
↳ | android.hardware.usb.UsbDevice |
This class represents a USB device attached to the android device with the android device
acting as the USB host.
Each device contains one or more UsbInterface
s, each of which contains a number of
UsbEndpoint
s (the channels via which data is transmitted over USB).
This class contains information (along with UsbInterface
and UsbEndpoint
)
that describes the capabilities of the USB device.
To communicate with the device, you open a UsbDeviceConnection
for the device
and use UsbRequest
to send and receive data on an endpoint.
UsbDeviceConnection#controlTransfer
is used for control requests on endpoint zero.
Developer Guides
For more information about communicating with USB hardware, read the USB developer guide.
Summary
Inherited constants | ||||
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Public methods | |
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int
|
describeContents()
Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. |
boolean
|
equals(Object o)
Indicates whether some other object is "equal to" this one. |
UsbConfiguration
|
getConfiguration(int index)
Returns the |
int
|
getConfigurationCount()
Returns the number of |
int
|
getDeviceClass()
Returns the devices's class field. |
int
|
getDeviceId()
Returns a unique integer ID for the device. |
static
int
|
getDeviceId(String name)
|
String
|
getDeviceName()
Returns the name of the device. |
static
String
|
getDeviceName(int id)
|
int
|
getDeviceProtocol()
Returns the device's protocol field. |
int
|
getDeviceSubclass()
Returns the device's subclass field. |
UsbInterface
|
getInterface(int index)
Returns the |
int
|
getInterfaceCount()
Returns the number of |
String
|
getManufacturerName()
Returns the manufacturer name of the device. |
int
|
getProductId()
Returns a product ID for the device. |
String
|
getProductName()
Returns the product name of the device. |
String
|
getSerialNumber()
Returns the serial number of the device. |
int
|
getVendorId()
Returns a vendor ID for the device. |
String
|
getVersion()
Returns the version number of the device. |
int
|
hashCode()
Returns a hash code value for the object. |
String
|
toString()
Returns a string representation of the object. |
void
|
writeToParcel(Parcel parcel, int flags)
Flatten this object in to a Parcel. |
Inherited methods | |||||||||||||||||||||||
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Fields
Public methods
describeContents
public int describeContents ()
Describe the kinds of special objects contained in this Parcelable
instance's marshaled representation. For example, if the object will
include a file descriptor in the output of writeToParcel(android.os.Parcel, int)
,
the return value of this method must include the
CONTENTS_FILE_DESCRIPTOR
bit.
Returns | |
---|---|
int |
a bitmask indicating the set of special object types marshaled
by this Parcelable object instance.
Value is either 0 or CONTENTS_FILE_DESCRIPTOR |
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 returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
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 | |
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o |
Object : This value may be null . |
Returns | |
---|---|
boolean |
true if this object is the same as the obj
argument; false otherwise. |
getConfiguration
public UsbConfiguration getConfiguration (int index)
Returns the UsbConfiguration
at the given index.
Parameters | |
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index |
int |
Returns | |
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UsbConfiguration |
the configuration
This value cannot be null . |
getConfigurationCount
public int getConfigurationCount ()
Returns the number of UsbConfiguration
s this device contains.
Returns | |
---|---|
int |
the number of configurations |
getDeviceClass
public int getDeviceClass ()
Returns the devices's class field.
Some useful constants for USB device classes can be found in UsbConstants
.
Returns | |
---|---|
int |
the devices's class |
getDeviceId
public int getDeviceId ()
Returns a unique integer ID for the device. This is a convenience for clients that want to use an integer to represent the device, rather than the device name. IDs are not persistent across USB disconnects.
Returns | |
---|---|
int |
the device ID |
getDeviceId
public static int getDeviceId (String name)
Parameters | |
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name |
String |
Returns | |
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int |
getDeviceName
public String getDeviceName ()
Returns the name of the device. In the standard implementation, this is the path of the device file for the device in the usbfs file system.
Returns | |
---|---|
String |
the device name
This value cannot be null . |
getDeviceName
public static String getDeviceName (int id)
Parameters | |
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id |
int |
Returns | |
---|---|
String |
getDeviceProtocol
public int getDeviceProtocol ()
Returns the device's protocol field.
Returns | |
---|---|
int |
the device's protocol |
getDeviceSubclass
public int getDeviceSubclass ()
Returns the device's subclass field.
Returns | |
---|---|
int |
the device's subclass |
getInterface
public UsbInterface getInterface (int index)
Returns the UsbInterface
at the given index.
For devices with multiple configurations, you will probably want to use
UsbConfiguration#getInterface
instead.
Parameters | |
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index |
int |
Returns | |
---|---|
UsbInterface |
the interface
This value cannot be null . |
getInterfaceCount
public int getInterfaceCount ()
Returns the number of UsbInterface
s this device contains.
For devices with multiple configurations, you will probably want to use
UsbConfiguration#getInterfaceCount
instead.
Returns | |
---|---|
int |
the number of interfaces |
getManufacturerName
public String getManufacturerName ()
Returns the manufacturer name of the device.
Returns | |
---|---|
String |
the manufacturer name, or null if the property could not be read |
getProductId
public int getProductId ()
Returns a product ID for the device.
Returns | |
---|---|
int |
the device product ID |
getProductName
public String getProductName ()
Returns the product name of the device.
Returns | |
---|---|
String |
the product name, or null if the property could not be read |
getSerialNumber
public String getSerialNumber ()
Returns the serial number of the device.
Returns | |
---|---|
String |
the serial number name, or null if the property could not be read |
Throws | |
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SecurityException |
if the app targets SDK >= android.os.Build.VERSION_CODES.Q
and the app does not have permission to read from the device. |
getVendorId
public int getVendorId ()
Returns a vendor ID for the device.
Returns | |
---|---|
int |
the device vendor ID |
getVersion
public String getVersion ()
Returns the version number of the device.
Returns | |
---|---|
String |
the device version
This value cannot be null . |
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 inequals
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 thehashCode
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 thehashCode
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. |
toString
public String toString ()
Returns a string representation of the object.
Returns | |
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String |
a string representation of the object. |
writeToParcel
public void writeToParcel (Parcel parcel, int flags)
Flatten this object in to a Parcel.
Parameters | |
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parcel |
Parcel : The Parcel in which the object should be written.
This value cannot be null . |
flags |
int : Additional flags about how the object should be written.
May be 0 or Parcelable.PARCELABLE_WRITE_RETURN_VALUE .
Value is either 0 or a combination of Parcelable.PARCELABLE_WRITE_RETURN_VALUE , and android.os.Parcelable.PARCELABLE_ELIDE_DUPLICATES |