com.github.nosan.embedded.cassandra.commons

Class FileLock

java.lang.Object

com.github.nosan.embedded.cassandra.commons.FileLock

All Implemented Interfaces:

AutoCloseable

public final class FileLock
extends Object
implements AutoCloseable

Helper class to lock a file. It is recommended practice to lock a file with a try with resources block, such as:

 
 class X {
   public void m() {
     try(FileLock lock = FileLock.of(lockFile)){
         if(lock.tryLock(1, TimeUnit.MINUTES){
             // locked
         } else {
             // not locked
         }
     }
 }}
 

An instance of this class must not be shared across different threads.

Since:

4.0.0

Author:

Dmytro Nosan

Method Summary

Modifier and Type	Method and Description
void	close() Closes the underlying FileChannel and releases all locks.
static FileLock	of(Path file) Creates a new FileLock instance for the specified file.
boolean	tryLock(long timeout, TimeUnit timeUnit) Acquires an exclusive lock on the file.

Methods inherited from class java.lang.Object

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

Method Detail

of

public static FileLock of(Path file)
                   throws IOException

Creates a new FileLock instance for the specified file.

Parameters:

file - the file that should be locked

Returns:

a new FileLock

Throws:

IOException - in the case of I/O errors

tryLock

public boolean tryLock(long timeout,
                       TimeUnit timeUnit)
                throws FileLockInterruptionException,
                       IOException

Acquires an exclusive lock on the file.

Parameters:

timeout - the maximum time to wait

timeUnit - the time unit of the timeout argument

Returns:

true if lock has been acquired otherwise false

Throws:

FileLockInterruptionException - If the invoking thread is interrupted while blocked in this method

IOException - If some other I/O error occurs

close

public void close()
           throws IOException

Closes the underlying FileChannel and releases all locks.

Specified by:

close in interface AutoCloseable

Throws:

IOException - If some other I/O error occurs