USBDevicePipe

java.lang.Object
- ohos.usb.USBDevicePipe

```
public class USBDevicePipe
extends Object
```
Provides methods for transferring data and control messages between USB devices.
Applications can get device descriptors from USBDevice to operate the USB devices.

从以下版本开始:

5

SystemCapability

SystemCapability.Usb#USB_MANAGER

字段概要

字段
限定符和类型字段说明

USBDevice device
Indicates a USBDevice.

字段
限定符和类型	字段	说明
`USBDevice`	`device`	Indicates a `USBDevice`.

构造器概要

构造器
构造器说明

USBDevicePipe(USBDevice device)

构造器
构造器	说明
`USBDevicePipe(USBDevice device)`

方法概要

所有方法实例方法具体方法
限定符和类型	方法	说明
`int`	`bulkTransfer(USBEndpoint epObj, byte[] buffer, int length, int timeout)`	Performs bulk data transfer on a specified endpoint.
`int`	`bulkTransfer(USBEndpoint epObj, byte[] buffer, int offset, int length, int timeout)`	Performs bulk data transfer on a specified endpoint.
`boolean`	`claimInterface(USBInterface interfaceObj, boolean force)`	Claims that a specified interface is exclusively occupied.
`void`	`close()`	Closes the `USBDevicePipeAdapter`.
`int`	`controlTransfer(int requestType, int request, int value, int index, byte[] buffer, int length, int timeout)`	Performs control message transfer on endpoint zero.
`int`	`controlTransfer(int requestType, int request, int value, int index, byte[] buffer, int offset, int length, int timeout)`	Performs control message transfer on endpoint zero.
`int`	`getFileDescriptor()`	Get the file descriptor.
`byte[]`	`getRawDescriptors()`	Get the original USB descriptors.
`String`	`getSerial()`	Get the serial number, in string.
`boolean`	`openByInt(String name, int fd)`	Performs an open process on the file descriptor.
`boolean`	`releaseInterface(USBInterface interfaceObj)`	Claims that a specified interface is released.
`USBRequest`	`requestWait()`	Waits for the result returned by the `USBRequest.queue(java.nio.ByteBuffer)` method.
`USBRequest`	`requestWait(long timeout)`	Waits for the result returned by the `USBRequest.queue(java.nio.ByteBuffer)` method.
`boolean`	`setConfiguration(USBConfig config)`	Sets the current USB configuration.
`boolean`	`setInterface(USBInterface interfaceObj)`	Sets the current USB interface.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 字段详细资料
  - device
```
public final USBDevice device
```
    Indicates a USBDevice.
- 构造器详细资料
  - USBDevicePipe
```
public USBDevicePipe(USBDevice device)
```
- 方法详细资料
  - bulkTransfer
```
public int bulkTransfer(USBEndpoint epObj,
                        byte[] buffer,
                        int length,
                        int timeout)
```
    Performs bulk data transfer on a specified endpoint.
    
    参数:
    
    epObj - the endpoint instance.
    
    buffer - Indicates the buffer for bulk data transfer.
    
    length - Indicates the length of the data to transfer.
    
    timeout - Indicates the transfer timeout period, in millisecond. The value 0 indicates that the transfer never times out.
    
    返回:
    
    Returns a value greater than or equal to 0 if the data transfer is successful; returns a negative value otherwise.
    
    从以下版本开始:
    
    5
  - bulkTransfer
```
public int bulkTransfer(USBEndpoint epObj,
                        byte[] buffer,
                        int offset,
                        int length,
                        int timeout)
```
    Performs bulk data transfer on a specified endpoint.
    
    参数:
    
    epObj - the endpoint instance.
    
    buffer - Indicates the buffer for bulk data transfer.
    
    offset - Indicates the offset from first byte in the buffer.
    
    length - Indicates the length of the data to transfer.
    
    timeout - Indicates the transfer timeout period, in millisecond. The value 0 indicates that the transfer never times out.
    
    返回:
    
    Returns a value greater than or equal to 0 if the data transfer is successful; returns a negative value otherwise.
    
    从以下版本开始:
    
    5
  - claimInterface
```
public boolean claimInterface(USBInterface interfaceObj,
                              boolean force)
```
    Claims that a specified interface is exclusively occupied. This must be done before transferring data to the endpoint of the interfaceObj interface.
    
    参数:
    
    interfaceObj - Indicates the interface to be exclusively occupied.
    
    force - Indicates whether the kernel driver is disconnected. The value true indicates that the kernel driver is disconnected. The value false indicates that the kernel driver is connected
    
    返回:
    
    Returns true if the claim is successful; returns false otherwise.
    
    从以下版本开始:
    
    5
  - close
```
public void close()
```
    Closes the USBDevicePipeAdapter.
  - controlTransfer
```
public int controlTransfer(int requestType,
                           int request,
                           int value,
                           int index,
                           byte[] buffer,
                           int offset,
                           int length,
                           int timeout)
```
    Performs control message transfer on endpoint zero.
    
    参数:
    
    requestType - Indicates the type of request initiated for control message transfer. For details, see USB protocol specifications. If the most significant bit is 1, data is written from the host. If the most significant bit is 0, data is written into the host.
    
    request - Indicates the request ID.
    
    value - Indicates the value of the transfer.
    
    index - Indicates the index of the transfer.
    
    buffer - Indicates the buffer from which data is to be transferred.
    
    offset - Indicates the offset address starting from 0 in the data buffer.
    
    length - Indicates the length of the data to transfer.
    
    timeout - Indicates the transfer timeout period, in millisecond.
    
    返回:
    
    Returns the number of bytes transferred; returns 0 if the transfer fails.
    
    从以下版本开始:
    
    5
  - controlTransfer
```
public int controlTransfer(int requestType,
                           int request,
                           int value,
                           int index,
                           byte[] buffer,
                           int length,
                           int timeout)
```
    Performs control message transfer on endpoint zero.
    
    参数:
    
    requestType - Indicates the type of request initiated for control message transfer. For details, see USB protocol specifications. If the most significant bit is 1, data is written from the host. If the most significant bit is 0, data is written into the host.
    
    request - Indicates the request ID.
    
    value - Indicates the value of the transfer.
    
    index - Indicates the index of the transfer.
    
    buffer - Indicates the buffer from which data is to be transferred.
    
    length - Indicates the length of the data to transfer.
    
    timeout - Indicates the transfer timeout period, in millisecond.
    
    返回:
    
    Returns the number of bytes transferred; returns 0 if the transfer fails.
    
    从以下版本开始:
    
    5
  - getFileDescriptor
```
public int getFileDescriptor()
```
    Get the file descriptor.
    
    返回:
    
    Returns the file descriptor.
    
    从以下版本开始:
    
    5
  - getRawDescriptors
```
public byte[] getRawDescriptors()
```
    Get the original USB descriptors.
    
    返回:
    
    Returns the original USB descriptors.
    
    从以下版本开始:
    
    5
  - getSerial
```
public String getSerial()
```
    Get the serial number, in string.
    
    返回:
    
    Returns the serial number.
    
    从以下版本开始:
    
    5
  - releaseInterface
```
public boolean releaseInterface(USBInterface interfaceObj)
```
    Claims that a specified interface is released.
    
    参数:
    
    interfaceObj - Indicates the interface to release.
    
    返回:
    
    Returns true if the release is successful; returns false otherwise.
    
    从以下版本开始:
    
    5
  - requestWait
```
public USBRequest requestWait(long timeout)
                       throws TimeoutException
```
    Waits for the result returned by the USBRequest.queue(java.nio.ByteBuffer) method. This is an asynchronous method call. If the operation times out, a timeout exception is thrown.
    
    参数:
    
    timeout - Indicates the timeout period, in milliseconds. The value 0 indicates no waiting.
    
    返回:
    
    Returns a USBRequest object.
    
    抛出:
    
    TimeoutException - Throws this exception if the specified timeout elapses.
    
    从以下版本开始:
    
    5
  - requestWait
```
public USBRequest requestWait()
```
    Waits for the result returned by the USBRequest.queue(java.nio.ByteBuffer) method.
    
    返回:
    
    Returns a USBRequest object.
    
    从以下版本开始:
    
    5
  - setConfiguration
```
public boolean setConfiguration(USBConfig config)
```
    Sets the current USB configuration.
    
    参数:
    
    config - The config instance.
    
    返回:
    
    Returns true if the setting is successful; returns false otherwise.
    
    从以下版本开始:
    
    5
  - setInterface
```
public boolean setInterface(USBInterface interfaceObj)
```
    Sets the current USB interface.
    
    参数:
    
    interfaceObj - Indicates a USBInterface object.
    
    返回:
    
    Returns true if the setting is successful; returns false otherwise.
    
    从以下版本开始:
    
    5
  - openByInt
```
public boolean openByInt(String name,
                         int fd)
```
    Performs an open process on the file descriptor.
    
    参数:
    
    name - Indicates the device name.
    
    fd - Indicates the file descriptor of the device connection.
    
    返回:
    
    Returns the result of the open process.

类 USBDevicePipe

字段概要

构造器概要

方法概要

从类继承的方法 java.lang.Object

字段详细资料

device

构造器详细资料

USBDevicePipe

方法详细资料

bulkTransfer

bulkTransfer

claimInterface

close

controlTransfer

controlTransfer

getFileDescriptor

getRawDescriptors

getSerial

releaseInterface

requestWait

requestWait

setConfiguration

setInterface

openByInt