ReliableFileDescriptor

java.lang.Object
- ohos.rpc.ReliableFileDescriptor

```
public class ReliableFileDescriptor
extends Object
```
Wraps a reliable FileDescriptor that can be accessed from multiple threads.
This class provides methods for creating a reliable data pipe and obtaining the wrapped FileDescriptor or native file descriptor.

从以下版本开始:

3

嵌套类概要

嵌套类
限定符和类型	类	说明
`static class`	`ReliableFileDescriptor.AutoCloseFileInputStream`	Represents a file input stream whose file descriptor is automatically closed when this stream is closed.
`static class`	`ReliableFileDescriptor.AutoCloseFileOutputStream`	Represents a file output stream whose file descriptor is automatically closed when this stream is closed.

构造器概要

构造器
构造器	说明
`ReliableFileDescriptor(FileDescriptor fd)`	A constructor used to create a `ReliableFileDescriptor` instance with the specified `FileDescriptor`.
`ReliableFileDescriptor(FileDescriptor fd, FileDescriptor commonFd)`	A constructor used to create a `ReliableFileDescriptor` instance with the specified `FileDescriptor` and the file descriptor used to check file status.

方法概要

所有方法静态方法实例方法具体方法
限定符和类型	方法	说明
`void`	`close()`	Closes this `ReliableFileDescriptor` object.
`static ReliableFileDescriptor[]`	`createPipe2()`	Creates an array of two `ReliableFileDescriptor` objects.
`static ReliableFileDescriptor[]`	`createReliablePipe()`	Creates an array of two `ReliableFileDescriptor` objects, with each containing a socket file descriptor.
`static ReliableFileDescriptor`	`dupFromSocket(Socket socket)`	Creates a `ReliableFileDescriptor` by duplicating the file descriptor of a specified socket.
`FileDescriptor`	`getFileDescriptor()`	Obtains the `FileDescriptor` wrapped in this `ReliableFileDescriptor`.
`long`	`getFileTotalSize()`	Obtains the size of the file matching this file descriptor.
`int`	`getNativeFd()`	Obtains the native file descriptor wrapped in this `ReliableFileDescriptor`.
`static ReliableFileDescriptor`	`takeChargeOfFileDescriptor(int fd)`	Creates a `ReliableFileDescriptor` by duplicating an existing file descriptor.

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

- 构造器详细资料
  - ReliableFileDescriptor
```
public ReliableFileDescriptor(FileDescriptor fd)
```
    A constructor used to create a ReliableFileDescriptor instance with the specified FileDescriptor.
    
    参数:
    
    fd - Indicates the FileDescriptor to wrap in the ReliableFileDescriptor instance.
    
    从以下版本开始:
    
    3
  - ReliableFileDescriptor
```
public ReliableFileDescriptor(FileDescriptor fd,
                              FileDescriptor commonFd)
```
    A constructor used to create a ReliableFileDescriptor instance with the specified FileDescriptor and the file descriptor used to check file status.
    
    参数:
    
    fd - Indicates the FileDescriptor to wrap in the ReliableFileDescriptor instance.
    
    commonFd - Indicates the file descriptor used to check whether the file is closed.
    
    从以下版本开始:
    
    3
- 方法详细资料
  - getFileDescriptor
```
public FileDescriptor getFileDescriptor()
```
    Obtains the FileDescriptor wrapped in this ReliableFileDescriptor.
    
    返回:
    
    Returns the FileDescriptor wrapped in this ReliableFileDescriptor.
    
    从以下版本开始:
    
    3
  - getNativeFd
```
public int getNativeFd()
```
    Obtains the native file descriptor wrapped in this ReliableFileDescriptor.
    This ReliableFileDescriptor still owns the file descriptor, which must be closed through this ReliableFileDescriptor.
    
    返回:
    
    Returns the native file descriptor wrapped in this ReliableFileDescriptor. Do not use the return value to close the file descriptor or pass the return value to any method that assumes ownership of the file descriptor. Otherwise, the file descriptor will be closed repeatedly.
    
    从以下版本开始:
    
    3
  - createPipe2
```
public static ReliableFileDescriptor[] createPipe2()
                                            throws OsHelperErrnoException
```
    Creates an array of two ReliableFileDescriptor objects.
    The array functions as a data pipe. One of the two objects is used to read data, and the other is used to write data.
    
    返回:
    
    Returns the created array.
    
    抛出:
    
    OsHelperErrnoException - Throws this exception if the array fails to be created.
    
    从以下版本开始:
    
    3
  - createReliablePipe
```
public static ReliableFileDescriptor[] createReliablePipe()
                                                   throws IOException,
                                                          OsHelperErrnoException
```
    Creates an array of two ReliableFileDescriptor objects, with each containing a socket file descriptor.
    The array functions as a data pipe. One of the two objects is used to read data, and the other is used to write data.
    
    返回:
    
    Returns the created array.
    
    抛出:
    
    OsHelperErrnoException - Throws this exception if the array fails to be created.
    
    IOException - Throws this exception if the socket pair used to operate the data pipe fails to be created.
    
    从以下版本开始:
    
    3
  - takeChargeOfFileDescriptor
```
public static ReliableFileDescriptor takeChargeOfFileDescriptor(int fd)
                                                         throws IOException,
                                                                OsHelperErrnoException
```
    Creates a ReliableFileDescriptor by duplicating an existing file descriptor.
    After the ReliableFileDescriptor is created, you must close it and the existing file descriptor.
    
    参数:
    
    fd - Indicates the existing file descriptor.
    
    返回:
    
    Returns the created ReliableFileDescriptor.
    
    抛出:
    
    OsHelperErrnoException - Throws this exception if operating the file descriptor fails.
    
    IOException - Throws this exception if the ReliableFileDescriptor fails to be created.
    
    从以下版本开始:
    
    4
  - dupFromSocket
```
public static ReliableFileDescriptor dupFromSocket(Socket socket)
                                            throws IOException,
                                                   OsHelperErrnoException
```
    Creates a ReliableFileDescriptor by duplicating the file descriptor of a specified socket.
    After the ReliableFileDescriptor is created, you must close it and the socket.
    
    参数:
    
    socket - Indicates the specified socket.
    
    返回:
    
    Returns the created ReliableFileDescriptor.
    
    抛出:
    
    OsHelperErrnoException - Throws this exception if operating the file descriptor fails.
    
    IOException - Throws this exception if the ReliableFileDescriptor fails to be created.
    
    从以下版本开始:
    
    4
  - getFileTotalSize
```
public long getFileTotalSize()
```
    Obtains the size of the file matching this file descriptor.
    
    返回:
    
    Returns the size of the file matching this file descriptor; returns -1 if this file descriptor does not match a file, for example, the file descriptor is a ReliableFileDescriptor obtained via Socket or Pipe.
    
    从以下版本开始:
    
    4
  - close
```
public void close()
```
    Closes this ReliableFileDescriptor object.
    
    从以下版本开始:
    
    5

类 ReliableFileDescriptor

嵌套类概要

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

ReliableFileDescriptor

ReliableFileDescriptor

方法详细资料

getFileDescriptor

getNativeFd

createPipe2

createReliablePipe

takeChargeOfFileDescriptor

dupFromSocket

getFileTotalSize

close