Package org.eclipse.rdf4j.sail.helpers

Class AbstractSail

  • All Implemented Interfaces:
    Sail
    Direct Known Subclasses:
    AbstractNotifyingSail, FedX, FedXConnection.SailBaseDefaultImpl
    public abstract class AbstractSail
extends Object
implements Sail
    An abstract Sail implementation that takes care of common sail tasks, including proper closing of active connections and a grace period for active connections during shutdown of the store.
    Author:
    Herko ter Horst, jeen, Arjohn Kampman

    • Field Detail

      • DEFAULT_CONNECTION_TIMEOUT

        protected static final long DEFAULT_CONNECTION_TIMEOUT
        Default connection timeout on shutdown: 20,000 milliseconds.
        See Also:
        Constant Field Values

      • DEFAULT_ITERATION_SYNC_THRESHOLD

        protected static final long DEFAULT_ITERATION_SYNC_THRESHOLD
        default value for the Iteration item sync threshold
        See Also:
        Constant Field Values

      • initializationLock

        protected final ReentrantReadWriteLock initializationLock
        Lock used to synchronize the initialization state of a sail.
        • write lock: initialize(), shutDown()
        • read lock: getConnection()

      • connectionTimeOut

        protected volatile long connectionTimeOut
        Connection timeout on shutdown (in ms). Defaults to DEFAULT_CONNECTION_TIMEOUT.

    • Constructor Detail

      • AbstractSail

        public AbstractSail()

    • Method Detail

      • debugEnabled

        protected static boolean debugEnabled()

      • setConnectionTimeOut

        public void setConnectionTimeOut​(long connectionTimeOut)
        Set connection timeout on shutdown (in ms).
        Parameters:
        connectionTimeOut - timeout (in ms)

      • setDataDir

        public void setDataDir​(File dataDir)
        Description copied from interface: Sail
        Sets the data directory for the Sail. The Sail can use this directory for storage of data, parameters, etc. This directory must be set before the Sail is initialized.
        Specified by:
        setDataDir in interface Sail

      • isInitialized

        protected boolean isInitialized()
        Checks whether the Sail has been initialized. Sails are initialized from initialization until shutdown.
        Returns:
        true if the Sail has been initialized, false otherwise.

      • init

        public void init()
          throws SailException
        Description copied from interface: Sail
        Initializes the Sail. Care should be taken that required initialization parameters have been set before this method is called. Please consult the specific Sail implementation for information about the relevant parameters.
        Specified by:
        init in interface Sail
        Throws:
        SailException - If the Sail could not be initialized.

      • initializeInternal

        protected void initializeInternal()
                           throws SailException
        Do store-specific operations to initialize the store. The default implementation of this method does nothing.
        Throws:
        SailException

      • shutDown

        public void shutDown()
              throws SailException
        Description copied from interface: Sail
        Shuts down the Sail, giving it the opportunity to synchronize any stale data. Care should be taken that all initialized Sails are being shut down before an application exits to avoid potential loss of data. Once shut down, a Sail can no longer be used until it is re-initialized.
        Specified by:
        shutDown in interface Sail
        Throws:
        SailException - If the Sail object encountered an error or unexpected situation internally.

      • shutDownInternal

        protected abstract void shutDownInternal()
                                  throws SailException
        Do store-specific operations to ensure proper shutdown of the store.
        Throws:
        SailException

      • getConnection

        public SailConnection getConnection()
                             throws SailException
        Description copied from interface: Sail
        Opens a connection on the Sail which can be used to query and update data. Depending on how the implementation handles concurrent access, a call to this method might block when there is another open connection on this Sail.
        Specified by:
        getConnection in interface Sail
        Throws:
        SailException - If no transaction could be started, for example because the Sail is not writable.

      • getConnectionInternal

        protected abstract SailConnection getConnectionInternal()
                                                 throws SailException
        Returns a store-specific SailConnection object.
        Returns:
        A connection to the store.
        Throws:
        SailException

      • connectionClosed

        protected void connectionClosed​(SailConnection connection)
        Signals to the store that the supplied connection has been closed; called by AbstractSailConnection.close().
        Parameters:
        connection - The connection that has been closed.

      • addSupportedIsolationLevel

        protected void addSupportedIsolationLevel​(IsolationLevels level)
        Appends the provided IsolationLevels to the SAIL's list of supported isolation levels.
        Parameters:
        level - a supported IsolationLevel.

      • removeSupportedIsolationLevel

        protected void removeSupportedIsolationLevel​(IsolationLevel level)
        Removes all occurrences of the provided IsolationLevels in the list of supported Isolation levels.
        Parameters:
        level - the isolation level to remove.

      • setSupportedIsolationLevels

        protected void setSupportedIsolationLevels​(List<IsolationLevel> supportedIsolationLevels)
        Sets the list of supported IsolationLevelss for this SAIL. The list is expected to be ordered in increasing complexity.
        Parameters:
        supportedIsolationLevels - a list of supported isolation levels.

      • setSupportedIsolationLevels

        protected void setSupportedIsolationLevels​(IsolationLevel... supportedIsolationLevels)
        Sets the list of supported IsolationLevelss for this SAIL. The list is expected to be ordered in increasing complexity.
        Parameters:
        supportedIsolationLevels - a list of supported isolation levels.

      • getSupportedIsolationLevels

        public List<IsolationLevel> getSupportedIsolationLevels()
        Description copied from interface: Sail
        Retrieve the IsolationLevels supported by this SAIL, ordered by increasing complexity.
        Specified by:
        getSupportedIsolationLevels in interface Sail
        Returns:
        a non-empty List of supported Isolation Levels, in order of increasing complexity. Every SAIL supports at least one IsolationLevel.

      • setDefaultIsolationLevel

        public void setDefaultIsolationLevel​(IsolationLevel defaultIsolationLevel)
        Sets the default IsolationLevel on which transactions in this Sail operate.
        Parameters:
        defaultIsolationLevel - The defaultIsolationLevel to set.

      • getIterationCacheSyncThreshold

        public long getIterationCacheSyncThreshold()
        Retrieves the currently configured threshold for syncing query evaluation iteration caches to disk.
        Returns:
        Returns the iterationCacheSyncThreshold.

      • setIterationCacheSyncThreshold

        public void setIterationCacheSyncThreshold​(long iterationCacheSyncThreshold)
        Set the threshold for syncing query evaluation iteration caches to disk.
        Parameters:
        iterationCacheSyncThreshold - The iterationCacheSyncThreshold to set.

      • isTrackResultSize

        public boolean isTrackResultSize()
        Returns the status of the result size tracking for the query plan. Useful to determine which parts of a query plan generated the most data.
        Returns:
        true if result size tracking is enabled.

      • setTrackResultSize

        public void setTrackResultSize​(boolean trackResultSize)
        Enable or disable results size tracking for the query plan. Useful to determine which parts of a query plan generated the most data.
        Parameters:
        trackResultSize - true to enable tracking.