Package de.dlr.proseo.storagemgr.utils

Class StorageFileLocker

java.lang.Object

de.dlr.proseo.storagemgr.utils.StorageFileLocker

public class StorageFileLocker
extends Object

A mechanism to lock and unlock files during the download process. It helps manage concurrent access to files by ensuring that only one process or thread can access a file at a time.

Author:

Denys Chaykovskiy

Constructor Summary

Constructors

Constructor	Description
StorageFileLocker(String path, long waitTime, long fileCheckMaxCycles)	Constructor

Method Summary

Modifier and Type	Method	Description
void	lockOrWaitUntilUnlockedAndLock()	Acquires a lock on the file.
void	unlock()	Releases the lock on the file by removing the file path from the productLockSet.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

StorageFileLocker

public StorageFileLocker(String path,
 long waitTime,
 long fileCheckMaxCycles)

Constructor

Parameters:

path - path of the file

waitTime - the wait time between each cycle of checking the file lock status

fileCheckMaxCycles - file check max cycles

Method Details

lockOrWaitUntilUnlockedAndLock

public void lockOrWaitUntilUnlockedAndLock()
                                    throws FileLockedAfterMaxCyclesException,
InterruptedException

Acquires a lock on the file. The method checks if the file is already locked by checking if it exists in the productLockSet. If it's not locked, it adds the file path to the set and breaks out of the loop. Otherwise, it waits for the specified waitTime and checks again. This process continues for a maximum of fileCheckMaxCycles cycles.

Throws:

FileLockedAfterMaxCyclesException - if the file is still locked after a maximum number of checks

InterruptedException - if the thread is interrupted while waiting for the concurrent access to terminate

unlock

public void unlock()

Releases the lock on the file by removing the file path from the productLockSet.