CachingDataStore (Apache Jackrabbit 2.20.16 API)

java.lang.Object
- org.apache.jackrabbit.core.data.AbstractDataStore
- - org.apache.jackrabbit.core.data.CachingDataStore

All Implemented Interfaces:: AsyncTouchCallback, AsyncUploadCallback, DataStore, MultiDataStoreAware

Direct Known Subclasses:: CachingFDS, S3DataStore, VFSDataStore

public abstract class CachingDataStore
extends AbstractDataStore
implements MultiDataStoreAware, AsyncUploadCallback, AsyncTouchCallback

A caching data store that consists of LocalCache and Backend. Backend is single source of truth. All methods first try to fetch information from LocalCache. If record is not available in LocalCache, then it is fetched from Backend and saved to LocalCache for further access. This class is designed to work without LocalCache and then all information is fetched from Backend. To disable LocalCache set setCacheSize(long) to 0. * Configuration:

 <DataStore class="org.apache.jackrabbit.aws.ext.ds.CachingDataStore">
 
     <param name="path" value="/data/datastore"/>
     <param name="config" value="${rep.home}/backend.properties"/>
     <param name="cacheSize" value="68719476736"/>
     <param name="secret" value="123456"/>
     <param name="setCachePurgeTrigFactor(double)" value="0.95d"/>
     <param name="cacheSize" value="0.85d"/>
     <param name="minRecordLength" value="1024"/>
     <param name="continueOnAsyncUploadFailure" value="false"/>
     <param name="concurrentUploadsThreads" value="10"/>
     <param name="asyncUploadLimit" value="100"/>
     <param name="uploadRetries" value="3"/>
     <param name="touchAsync" value="false"/>
     <param name="proactiveCaching" value="true"/>
     <param name="recLengthCacheSize" value="200"/>
 </DataStore>

Field Summary

Fields
Modifier and Type	Field and Description
`protected Map<DataIdentifier,Long>`	`asyncDownloadCache` In memory map to hold in-progress asynchronous downloads.
`protected Map<DataIdentifier,Long>`	`asyncTouchCache` In memory map to hold in-progress asynchronous touch.
`protected Backend`	`backend`
`protected Map<DataIdentifier,WeakReference<DataIdentifier>>`	`inUse` All data identifiers that are currently in use are in this set until they are garbage collected.
`protected Map<DataIdentifier,Long>`	`recLenCache` In memory cache to hold `DataRecord.getLength()` against `DataIdentifier`
`protected Map<DataIdentifier,Integer>`	`uploadRetryMap` In memory map to hold failed asynchronous upload `DataIdentifier` and its retry count.

Fields inherited from class org.apache.jackrabbit.core.data.AbstractDataStore
DIGEST

Constructor Summary

Constructors
Constructor and Description

CachingDataStore()

Constructors
Constructor and Description
`CachingDataStore()`

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`DataRecord`	`addRecord(InputStream input)` Creates a new data record in `Backend`.
`void`	`clearInUse()` Clear the in-use list.
`void`	`close()` Close the data store
`boolean`	`confirmDelete(DataIdentifier identifier)` Method to confirm that identifier can be deleted from `Backend`
`protected abstract Backend`	`createBackend()`
`int`	`deleteAllOlderThan(long min)` Delete objects that have a modified date older than the specified date.
`void`	`deleteFromCache(DataIdentifier identifier)`
`void`	`deleteRecord(DataIdentifier identifier)` This method deletes record from `Backend` and then from `LocalCache`
`Iterator<DataIdentifier>`	`getAllIdentifiers()` Retrieves all identifiers from `Backend`.
`int`	`getAsyncUploadLimit()`
`Backend`	`getBackend()`
`double`	`getCachePurgeResizeFactor()`
`double`	`getCachePurgeTrigFactor()`
`long`	`getCacheSize()`
`int`	`getConcurrentUploadsThreads()`
`String`	`getConfig()` Return path of configuration properties.
`long`	`getLastModified(DataIdentifier identifier)` Return lastModified of record from `Backend` assuming `Backend` as a single source of truth.
`long`	`getLength(DataIdentifier identifier)` Return the length of record from `LocalCache` if available, otherwise retrieve it from `Backend`.
`protected abstract String`	`getMarkerFile()`
`int`	`getMinRecordLength()` Return mininum object length.
`protected byte[]`	`getOrCreateReferenceKey()` Returns the reference key of this data store.
`String`	`getPath()`
`Set<String>`	`getPendingUploads()`
`DataRecord`	`getRecord(DataIdentifier identifier)` Returns the identified data record.
`DataRecord`	`getRecordIfStored(DataIdentifier identifier)` Get a data record for the given identifier or null it data record doesn't exist in `Backend`
`int`	`getUploadRetries()`
`void`	`init(String homeDir)` Initialized the data store.
`boolean`	`isContinueOnAsyncUploadFailure()`
`boolean`	`isInUse(DataIdentifier identifier)`
`void`	`onAbort(AsyncTouchResult result)` Callback method for aborted asynchronous touch.
`void`	`onAbort(AsyncUploadResult result)` Callback method for aborted asynchronous upload.
`void`	`onFailure(AsyncTouchResult result)` Callback method for failed asynchronous touch.
`void`	`onFailure(AsyncUploadResult result)` Callback method for failed asynchronous upload.
`void`	`onSuccess(AsyncTouchResult result)` Callback method for successful asynchronous touch.
`void`	`onSuccess(AsyncUploadResult result)` Callback method for successful asynchronous upload.
`void`	`setAsyncUploadLimit(int asyncUploadLimit)`
`void`	`setCachePurgeResizeFactor(double cachePurgeResizeFactor)` Set purge resize factor of `LocalCache`.
`void`	`setCachePurgeTrigFactor(double cachePurgeTrigFactor)` Set purge trigger factor of `LocalCache`.
`void`	`setCacheSize(long cacheSize)` Set size of `LocalCache`.
`void`	`setConcurrentUploadsThreads(int concurrentUploadsThreads)`
`void`	`setConfig(String config)` Set the configuration properties path.
`void`	`setContinueOnAsyncUploadFailure(boolean continueOnAsyncUploadFailure)`
`void`	`setMinRecordLength(int minRecordLength)` Set the minimum object length.
`void`	`setPath(String path)` Set path of `LocalCache`.
`void`	`setProactiveCaching(boolean proactiveCaching)`
`void`	`setRecLengthCacheSize(int recLengthCacheSize)`
`void`	`setSecret(String secret)` Setter for configuration based secret
`void`	`setTouchAsync(boolean touchAsync)`
`void`	`setUploadRetries(int uploadRetries)`
`void`	`updateModifiedDateOnAccess(long before)` From now on, update the modified date of an object even when accessing it.

Methods inherited from class org.apache.jackrabbit.core.data.AbstractDataStore
encodeHexString, getRecordFromReference, getReferenceFromIdentifier

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

- Field Detail
  - inUse
```
protected Map<DataIdentifier,WeakReference<DataIdentifier>> inUse
```
    All data identifiers that are currently in use are in this set until they are garbage collected.
  - uploadRetryMap
```
protected final Map<DataIdentifier,Integer> uploadRetryMap
```
    In memory map to hold failed asynchronous upload DataIdentifier and its retry count. Once if all retries are exhausted or file is successfully uploaded, then corresponding entry is flushed from the map. As all failed uploads are synchronously uploaded at startup, this map is not required to be persisted.
  - asyncTouchCache
```
protected final Map<DataIdentifier,Long> asyncTouchCache
```
    In memory map to hold in-progress asynchronous touch. Once touch is successful corresponding entry is flushed from the map.
  - asyncDownloadCache
```
protected final Map<DataIdentifier,Long> asyncDownloadCache
```
    In memory map to hold in-progress asynchronous downloads. Once download is finished corresponding entry is flushed from the map.
  - recLenCache
```
protected Map<DataIdentifier,Long> recLenCache
```
    In memory cache to hold DataRecord.getLength() against DataIdentifier
  - backend
```
protected Backend backend
```
- Constructor Detail
  - CachingDataStore
```
public CachingDataStore()
```
- Method Detail
  - createBackend
```
protected abstract Backend createBackend()
```
  - getMarkerFile
```
protected abstract String getMarkerFile()
```
  - init
```
public void init(String homeDir)
          throws RepositoryException
```
    Initialized the data store. If the path is not set, <repository home>/repository/datastore is used. This directory is automatically created if it does not yet exist. During first initialization, it upload all files from local datastore to backed and local datastore act as a local cache.
    
    Specified by:
    
    init in interface DataStore
    
    Parameters:
    
    homeDir - the home directory of the repository
    
    Throws:
    
    RepositoryException
  - addRecord
```
public DataRecord addRecord(InputStream input)
                     throws DataStoreException
```
    Creates a new data record in Backend. The stream is first consumed and the contents are saved in a temporary file and the AbstractDataStore.DIGEST message digest of the stream is calculated. If a record with the same AbstractDataStore.DIGEST digest (and length) is found then it is returned. Otherwise new record is created in Backend and the temporary file is moved in place to LocalCache.
    
    Specified by:
    
    addRecord in interface DataStore
    
    Parameters:
    
    input - binary stream
    
    Returns:
    
    CachingDataRecord
    
    Throws:
    
    DataStoreException - if the record could not be created.
  - getRecord
```
public DataRecord getRecord(DataIdentifier identifier)
                     throws DataStoreException
```
    Description copied from interface: DataStore
    
    Returns the identified data record. The given identifier should be the identifier of a previously saved data record. Since records are never removed, there should never be cases where the identified record is not found. Abnormal cases like that are treated as errors and handled by throwing an exception.
    
    Specified by:
    
    getRecord in interface DataStore
    
    Overrides:
    
    getRecord in class AbstractDataStore
    
    Parameters:
    
    identifier - data identifier
    
    Returns:
    
    identified data record
    
    Throws:
    
    DataStoreException - if the data store could not be accessed, or if the given identifier is invalid
  - getRecordIfStored
```
public DataRecord getRecordIfStored(DataIdentifier identifier)
                             throws DataStoreException
```
    Get a data record for the given identifier or null it data record doesn't exist in Backend
    
    Specified by:
    
    getRecordIfStored in interface DataStore
    
    Parameters:
    
    identifier - identifier of record.
    
    Returns:
    
    the CachingDataRecord or null.
    
    Throws:
    
    DataStoreException - if the data store could not be accessed
  - updateModifiedDateOnAccess
```
public void updateModifiedDateOnAccess(long before)
```
    Description copied from interface: DataStore
    
    From now on, update the modified date of an object even when accessing it. Usually, the modified date is only updated when creating a new object, or when a new link is added to an existing object. When this setting is enabled, even getLength() will update the modified date.
    
    Specified by:
    
    updateModifiedDateOnAccess in interface DataStore
    
    Parameters:
    
    before - - update the modified date to the current time if it is older than this value
  - getAllIdentifiers
```
public Iterator<DataIdentifier> getAllIdentifiers()
                                           throws DataStoreException
```
    Retrieves all identifiers from Backend.
    
    Specified by:
    
    getAllIdentifiers in interface DataStore
    
    Returns:
    
    an iterator over all DataIdentifier objects
    
    Throws:
    
    DataStoreException - if the list could not be read
  - deleteRecord
```
public void deleteRecord(DataIdentifier identifier)
                  throws DataStoreException
```
    This method deletes record from Backend and then from LocalCache
    
    Specified by:
    
    deleteRecord in interface MultiDataStoreAware
    
    Parameters:
    
    identifier - data identifier
    
    Throws:
    
    DataStoreException - if the data store could not be accessed, or if the given identifier is invalid
  - deleteAllOlderThan
```
public int deleteAllOlderThan(long min)
                       throws DataStoreException
```
    Description copied from interface: DataStore
    
    Delete objects that have a modified date older than the specified date.
    
    Specified by:
    
    deleteAllOlderThan in interface DataStore
    
    Parameters:
    
    min - the minimum time
    
    Returns:
    
    the number of data records deleted
    
    Throws:
    
    DataStoreException
  - getLastModified
```
public long getLastModified(DataIdentifier identifier)
                     throws DataStoreException
```
    Return lastModified of record from Backend assuming Backend as a single source of truth.
    
    Throws:
    
    DataStoreException
  - getLength
```
public long getLength(DataIdentifier identifier)
               throws DataStoreException
```
    Return the length of record from LocalCache if available, otherwise retrieve it from Backend.
    
    Throws:
    
    DataStoreException
  - getOrCreateReferenceKey
```
protected byte[] getOrCreateReferenceKey()
                                  throws DataStoreException
```
    Description copied from class: AbstractDataStore
    
    Returns the reference key of this data store. If one does not already exist, it is automatically created in an implementation-specific way. The default implementation simply creates a temporary random key that's valid only until the data store gets restarted. Subclasses can override and/or decorate this method to support a more persistent reference key.
    This method is called only once during the lifetime of a data store instance and the return value is cached in memory, so it's no problem if the implementation is slow.
    
    Overrides:
    
    getOrCreateReferenceKey in class AbstractDataStore
    
    Returns:
    
    reference key
    
    Throws:
    
    DataStoreException - if the key is not available
  - getPendingUploads
```
public Set<String> getPendingUploads()
```
  - deleteFromCache
```
public void deleteFromCache(DataIdentifier identifier)
                     throws DataStoreException
```
    Throws:
    
    DataStoreException
  - onSuccess
```
public void onSuccess(AsyncUploadResult result)
```
    Description copied from interface: AsyncUploadCallback
    
    Callback method for successful asynchronous upload.
    
    Specified by:
    
    onSuccess in interface AsyncUploadCallback
  - onFailure
```
public void onFailure(AsyncUploadResult result)
```
    Description copied from interface: AsyncUploadCallback
    
    Callback method for failed asynchronous upload.
    
    Specified by:
    
    onFailure in interface AsyncUploadCallback
  - onAbort
```
public void onAbort(AsyncUploadResult result)
```
    Description copied from interface: AsyncUploadCallback
    
    Callback method for aborted asynchronous upload.
    
    Specified by:
    
    onAbort in interface AsyncUploadCallback
  - onSuccess
```
public void onSuccess(AsyncTouchResult result)
```
    Description copied from interface: AsyncTouchCallback
    
    Callback method for successful asynchronous touch.
    
    Specified by:
    
    onSuccess in interface AsyncTouchCallback
  - onFailure
```
public void onFailure(AsyncTouchResult result)
```
    Description copied from interface: AsyncTouchCallback
    
    Callback method for failed asynchronous touch.
    
    Specified by:
    
    onFailure in interface AsyncTouchCallback
  - onAbort
```
public void onAbort(AsyncTouchResult result)
```
    Description copied from interface: AsyncTouchCallback
    
    Callback method for aborted asynchronous touch.
    
    Specified by:
    
    onAbort in interface AsyncTouchCallback
  - confirmDelete
```
public boolean confirmDelete(DataIdentifier identifier)
```
    Method to confirm that identifier can be deleted from Backend
    
    Parameters:
    
    identifier -
    
    Returns:
  - clearInUse
```
public void clearInUse()
```
    Description copied from interface: DataStore
    
    Clear the in-use list. This is only used for testing to make the the garbage collection think that objects are no longer in use.
    
    Specified by:
    
    clearInUse in interface DataStore
  - isInUse
```
public boolean isInUse(DataIdentifier identifier)
```
  - close
```
public void close()
           throws DataStoreException
```
    Description copied from interface: DataStore
    
    Close the data store
    
    Specified by:
    
    close in interface DataStore
    
    Throws:
    
    DataStoreException - if a problem occurred
  - setSecret
```
public void setSecret(String secret)
```
    Setter for configuration based secret
    
    Parameters:
    
    secret - the secret used to sign reference binaries
  - setMinRecordLength
```
public void setMinRecordLength(int minRecordLength)
```
    Set the minimum object length.
    
    Parameters:
    
    minRecordLength - the length
  - getMinRecordLength
```
public int getMinRecordLength()
```
    Return mininum object length.
    
    Specified by:
    
    getMinRecordLength in interface DataStore
    
    Returns:
    
    the minimum size in bytes
  - getConfig
```
public String getConfig()
```
    Return path of configuration properties.
    
    Returns:
    
    path of configuration properties.
  - setConfig
```
public void setConfig(String config)
```
    Set the configuration properties path.
    
    Parameters:
    
    config - path of configuration properties.
  - getCacheSize
```
public long getCacheSize()
```
    Returns:
    
    size of LocalCache.
  - setCacheSize
```
public void setCacheSize(long cacheSize)
```
    Set size of LocalCache.
    
    Parameters:
    
    cacheSize - size of LocalCache.
  - getPath
```
public String getPath()
```
    Returns:
    
    path of LocalCache.
  - setPath
```
public void setPath(String path)
```
    Set path of LocalCache.
    
    Parameters:
    
    path - of LocalCache.
  - getCachePurgeTrigFactor
```
public double getCachePurgeTrigFactor()
```
    Returns:
    
    Purge trigger factor of LocalCache.
  - setCachePurgeTrigFactor
```
public void setCachePurgeTrigFactor(double cachePurgeTrigFactor)
```
    Set purge trigger factor of LocalCache.
    
    Parameters:
    
    cachePurgeTrigFactor - purge trigger factor.
  - getCachePurgeResizeFactor
```
public double getCachePurgeResizeFactor()
```
    Returns:
    
    Purge resize factor of LocalCache.
  - setCachePurgeResizeFactor
```
public void setCachePurgeResizeFactor(double cachePurgeResizeFactor)
```
    Set purge resize factor of LocalCache.
    
    Parameters:
    
    cachePurgeResizeFactor - purge resize factor.
  - getConcurrentUploadsThreads
```
public int getConcurrentUploadsThreads()
```
  - setConcurrentUploadsThreads
```
public void setConcurrentUploadsThreads(int concurrentUploadsThreads)
```
  - getAsyncUploadLimit
```
public int getAsyncUploadLimit()
```
  - setAsyncUploadLimit
```
public void setAsyncUploadLimit(int asyncUploadLimit)
```
  - isContinueOnAsyncUploadFailure
```
public boolean isContinueOnAsyncUploadFailure()
```
  - setContinueOnAsyncUploadFailure
```
public void setContinueOnAsyncUploadFailure(boolean continueOnAsyncUploadFailure)
```
  - getUploadRetries
```
public int getUploadRetries()
```
  - setUploadRetries
```
public void setUploadRetries(int uploadRetries)
```
  - setTouchAsync
```
public void setTouchAsync(boolean touchAsync)
```
  - setProactiveCaching
```
public void setProactiveCaching(boolean proactiveCaching)
```
  - setRecLengthCacheSize
```
public void setRecLengthCacheSize(int recLengthCacheSize)
```
  - getBackend
```
public Backend getBackend()
```

Class CachingDataStore

Field Summary

Fields inherited from class org.apache.jackrabbit.core.data.AbstractDataStore

Constructor Summary

Method Summary

Methods inherited from class org.apache.jackrabbit.core.data.AbstractDataStore

Methods inherited from class java.lang.Object

Field Detail

inUse

uploadRetryMap

asyncTouchCache

asyncDownloadCache

recLenCache

backend

Constructor Detail

CachingDataStore

Method Detail

createBackend

getMarkerFile

init

addRecord

getRecord

getRecordIfStored

updateModifiedDateOnAccess

getAllIdentifiers

deleteRecord

deleteAllOlderThan

getLastModified

getLength

getOrCreateReferenceKey

getPendingUploads

deleteFromCache

onSuccess

onFailure

onAbort

onSuccess

onFailure

onAbort

confirmDelete

clearInUse

isInUse

close

setSecret

setMinRecordLength

getMinRecordLength

getConfig

setConfig

getCacheSize

setCacheSize

getPath

setPath

getCachePurgeTrigFactor

setCachePurgeTrigFactor

getCachePurgeResizeFactor

setCachePurgeResizeFactor

getConcurrentUploadsThreads

setConcurrentUploadsThreads

getAsyncUploadLimit

setAsyncUploadLimit

isContinueOnAsyncUploadFailure

setContinueOnAsyncUploadFailure

getUploadRetries

setUploadRetries

setTouchAsync

setProactiveCaching

setRecLengthCacheSize

getBackend