org.apache.flink.util

类 FileLock

java.lang.Object

org.apache.flink.util.FileLock

@Internal
public class FileLock
extends Object

A file lock used for avoiding race condition among multiple threads/processes.

构造器概要

构造器

构造器和说明
FileLock(String fullPath) Initialize a FileLock using a file located at fullPath.
FileLock(String parentDir, String fileName) Initialize a FileLock using a file located at parentDir/fileName.

方法概要

限定符和类型	方法和说明
static FileLock	inTempFolder(String fileName) Initialize a FileLock using a file located inside temp folder.
boolean	isValid() Check whether a FileLock is actually holding the lock.
boolean	tryLock() Try to acquire a lock on the locking file.
void	unlock() Release the file lock.
void	unlockAndDestroy() Release the file lock, close the fileChannel and FileOutputStream then try deleting the locking file if other file lock does not need it, which means the lock will not be used anymore.

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

FileLock

public FileLock(String fullPath)

Initialize a FileLock using a file located at fullPath.

参数:

fullPath - The path of the locking file

FileLock

public FileLock(String parentDir,
                String fileName)

Initialize a FileLock using a file located at parentDir/fileName.

参数:

parentDir - The parent dir of the locking file

fileName - The name of the locking file

方法详细资料

inTempFolder

public static FileLock inTempFolder(String fileName)

Initialize a FileLock using a file located inside temp folder.

参数:

fileName - The name of the locking file

返回:

The initialized FileLock

tryLock

public boolean tryLock()
                throws IOException

Try to acquire a lock on the locking file. This method immediately returns whenever the lock is acquired or not.

返回:

True if successfully acquired the lock

抛出:

IOException - If the file path is invalid

unlock

public void unlock()
            throws IOException

Release the file lock.

抛出:

IOException - If the FileChannel is closed

unlockAndDestroy

public void unlockAndDestroy()
                      throws IOException

Release the file lock, close the fileChannel and FileOutputStream then try deleting the locking file if other file lock does not need it, which means the lock will not be used anymore.

抛出:

IOException - If an I/O error occurs

isValid

public boolean isValid()

Check whether a FileLock is actually holding the lock.

返回:

True if it is actually holding the lock