Package org.apache.jackrabbit.core.data

Class MultiDataStore

java.lang.Object
org.apache.jackrabbit.core.data.MultiDataStore
All Implemented Interfaces:
DataStore
public class MultiDataStore extends Object implements DataStore
A MultiDataStore can handle two independent DataStores.

Attention: You will lost the global single instance mechanism !

It can be used if you have two storage systems. One for fast access and a other one like a archive DataStore on a slower storage system. All Files will be added to the primary DataStore. On read operations first the primary dataStore will be used and if no Record is found the archive DataStore will be used. The GarabageCollector will only remove files from the archive DataStore.

The internal MoveDataTask will be started automatically and could be configured with the following properties.

The Configuration: 

 <DataStore class="org.apache.jackrabbit.core.data.MultiDataStore">
     <param name="maxAge" value="60"/>
     <param name="moveDataTaskSleep" value="604800"/>
     <param name="moveDataTaskFirstRunHourOfDay" value="1"/>
     <param name="sleepBetweenRecords" value="100"/>
     <param name="delayedDelete" value="false"/>
     <param name="delayedDeleteSleep" value="86400"/>
     <param name="primary" value="org.apache.jackrabbit.core.data.db.DbDataStore">
        <param .../>
     </param>
     <param name="archive" value="org.apache.jackrabbit.core.data.FileDataStore">
        <param .../>
     </param>
 </DataStore>
  • maxAge: defines how many days the content will reside in the primary data store. DataRecords that have been added before this time span will be moved to the archive data store. (default = 60)
  • moveDataTaskSleep: specifies the sleep time of the moveDataTaskThread in seconds. (default = 60 * 60 * 24 * 7, which equals 7 days)
  • moveDataTaskNextRunHourOfDay: specifies the hour at which the moveDataTaskThread initiates its first run (default = 1 which means 01:00 at night)
  • sleepBetweenRecords: specifies the delay in milliseconds between scanning data records (default = 100)
  • delayedDelete: its possible to delay the delete operation on the primary data store. The DataIdentifiers will be written to a temporary file. The file will be processed after a defined sleep (see delayedDeleteSleep) It's useful if you like to create a snapshot of the primary data store backend in the meantime before the data will be deleted. (default = false)
  • delayedDeleteSleep: specifies the sleep time of the delayedDeleteTaskThread in seconds. (default = 60 * 60 * 24, which equals 1 day). This means the delayed delete from the primary data store will be processed after one day.

  • Constructor Details

    • MultiDataStore

      public MultiDataStore()

  • Method Details

    • setPrimaryDataStore

      public void setPrimaryDataStore(DataStore dataStore)
      Setter for the primary dataStore
      Parameters:
      dataStore -

    • setArchiveDataStore

      public void setArchiveDataStore(DataStore dataStore)
      Setter for the archive dataStore
      Parameters:
      dataStore -

    • getRecordIfStored

      public DataRecord getRecordIfStored(DataIdentifier identifier) throws DataStoreException
      Check if a record for the given identifier exists in the primary data store. If not found there it will be returned from the archive data store. If no record exists, this method returns null.
      Specified by:
      getRecordIfStored in interface DataStore
      Parameters:
      identifier - data identifier
      Returns:
      the record if found, and null if not
      Throws:
      DataStoreException - if the data store could not be accessed

    • getRecord

      public DataRecord getRecord(DataIdentifier identifier) throws DataStoreException
      Returns the identified data record from the primary data store. If not found there it will be returned from the archive data store. 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
      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

    • addRecord

      public DataRecord addRecord(InputStream stream) throws DataStoreException
      Creates a new data record in the primary data store. The given binary stream is consumed and a binary record containing the consumed stream is created and returned. If the same stream already exists in another record, then that record is returned instead of creating a new one.

      The given stream is consumed and not closed by this method. It is the responsibility of the caller to close the stream. A typical call pattern would be: 

           InputStream stream = ...;
     try {
         record = store.addRecord(stream);
     } finally {
         stream.close();
     }
      Specified by:
      addRecord in interface DataStore
      Parameters:
      stream - binary stream
      Returns:
      data record that contains the given stream
      Throws:
      DataStoreException - if the data store could not be accessed

    • updateModifiedDateOnAccess

      public void updateModifiedDateOnAccess(long before)
      From now on, update the modified date of an object even when accessing it in the archive data store. 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

    • deleteAllOlderThan

      public int deleteAllOlderThan(long min) throws DataStoreException
      Delete objects that have a modified date older than the specified date from the archive data store.
      Specified by:
      deleteAllOlderThan in interface DataStore
      Parameters:
      min - the minimum time
      Returns:
      the number of data records deleted
      Throws:
      DataStoreException

    • getAllIdentifiers

      public Iterator<DataIdentifier> getAllIdentifiers() throws DataStoreException
      Get all identifiers from the archive data store.
      Specified by:
      getAllIdentifiers in interface DataStore
      Returns:
      an iterator over all DataIdentifier objects
      Throws:
      DataStoreException - if the list could not be read

    • getRecordFromReference

      public DataRecord getRecordFromReference(String reference) throws DataStoreException
      Description copied from interface: DataStore
      Returns the record that matches the given binary reference. Returns null if the reference is invalid, for example if it points to a record that does not exist.
      Specified by:
      getRecordFromReference in interface DataStore
      Parameters:
      reference - binary reference
      Returns:
      matching record, or null
      Throws:
      DataStoreException - if the data store could not be accessed

    • init

      public void init(String homeDir) throws RepositoryException
      Initialized the data store
      Specified by:
      init in interface DataStore
      Parameters:
      homeDir - the home directory of the repository
      Throws:
      RepositoryException

    • getMinRecordLength

      public int getMinRecordLength()
      Get the minimum size of an object that should be stored in the primary data store.
      Specified by:
      getMinRecordLength in interface DataStore
      Returns:
      the minimum size in bytes

    • close

      public void close() throws DataStoreException
      Close the data store
      Specified by:
      close in interface DataStore
      Throws:
      DataStoreException - if a problem occurred

    • clearInUse

      public void clearInUse()
      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

    • getMaxAge

      public int getMaxAge()

    • setMaxAge

      public void setMaxAge(int maxAge)

    • getMoveDataTaskSleep

      public int getMoveDataTaskSleep()

    • getMoveDataTaskFirstRunHourOfDay

      public int getMoveDataTaskFirstRunHourOfDay()

    • setMoveDataTaskSleep

      public void setMoveDataTaskSleep(int sleep)

    • setMoveDataTaskFirstRunHourOfDay

      public void setMoveDataTaskFirstRunHourOfDay(int hourOfDay)

    • setSleepBetweenRecords

      public void setSleepBetweenRecords(long millis)

    • getSleepBetweenRecords

      public long getSleepBetweenRecords()

    • isDelayedDelete

      public boolean isDelayedDelete()

    • setDelayedDelete

      public void setDelayedDelete(boolean delayedDelete)

    • getDelayedDeleteSleep

      public long getDelayedDeleteSleep()

    • setDelayedDeleteSleep

      public void setDelayedDeleteSleep(long delayedDeleteSleep)