FileInfoBackingCache.CachedFileInfo (Apache BookKeeper :: Parent 4.18.0-SNAPSHOT API)

java.lang.Object
- org.apache.bookkeeper.common.util.Watchable<LastAddConfirmedUpdateNotification>
- - org.apache.bookkeeper.bookie.FileInfo
  - - org.apache.bookkeeper.bookie.FileInfoBackingCache.CachedFileInfo

All Implemented Interfaces:

Recyclable

Enclosing class:

FileInfoBackingCache
```
class FileInfoBackingCache.CachedFileInfo
extends FileInfo
```

Nested Class Summary
- Nested classes/interfaces inherited from class org.apache.bookkeeper.bookie.FileInfo
  FileInfo.FileInfoDeletedException

Field Summary

Fields
Modifier and Type Field Description

(package private) long ledgerId

(package private) java.util.concurrent.atomic.AtomicInteger refCount
- Fields inherited from class org.apache.bookkeeper.bookie.FileInfo
  CURRENT_HEADER_VERSION, headerVersion, masterKey, mode, NO_MASTER_KEY, SIGNATURE, START_OF_DATA, STATE_FENCED_BIT, V0, V1

Constructor Summary

Constructors
Constructor Description

CachedFileInfo(long ledgerId, java.io.File lf, byte[] masterKey)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`(package private) int`	`getRefCount()`
`(package private) void`	`release()`
`java.lang.String`	`toString()`
`(package private) boolean`	`tryRetain()`	Attempt to retain the file info.

Methods inherited from class org.apache.bookkeeper.bookie.FileInfo
cancelWaitForLastAddConfirmedUpdate, checkOpen, close, delete, flushHeader, getExplicitLac, getLastAddConfirmed, getLf, getMasterKey, getSizeSinceLastWrite, isClosed, isDeleted, isFenced, isSameFile, moveToNewLocation, read, readHeader, setExplicitLac, setFenced, setLastAddConfirmed, size, waitForLastAddConfirmedUpdate, write

Methods inherited from class org.apache.bookkeeper.common.util.Watchable
addWatcher, deleteWatcher, deleteWatchers, notifyWatchers, recycle

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - ledgerId
```
final long ledgerId
```
  - refCount
```
final java.util.concurrent.atomic.AtomicInteger refCount
```
- Constructor Detail
  - CachedFileInfo
```
CachedFileInfo(long ledgerId,
               java.io.File lf,
               byte[] masterKey)
        throws java.io.IOException
```
    Throws:
    
    java.io.IOException
- Method Detail
  - tryRetain
```
boolean tryRetain()
```
    Attempt to retain the file info. When a client obtains a fileinfo from a container object, but that container object may release the fileinfo before the client has a chance to call retain. In this case, the file info could be released and the destroyed before we ever get a chance to use it.
    tryRetain avoids this problem, by doing a compare-and-swap on the reference count. If the refCount is negative, it means that the fileinfo is being cleaned up, and this fileinfo object should not be used. This works in tandem with #markDead, which will only set the refCount to negative if noone currently has it retained (i.e. the refCount is 0).
    
    Returns:
    
    true if we managed to increment the refcount, false otherwise
  - getRefCount
```
int getRefCount()
```
  - release
```
void release()
```
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object