Package org.eclipse.jetty.server.session

Class AbstractSessionCache

  • All Implemented Interfaces:
    SessionCache, org.eclipse.jetty.util.component.Container, org.eclipse.jetty.util.component.Destroyable, org.eclipse.jetty.util.component.Dumpable, org.eclipse.jetty.util.component.LifeCycle
    Direct Known Subclasses:
    DefaultSessionCache, NullSessionCache
    @ManagedObject
public abstract class AbstractSessionCache
extends org.eclipse.jetty.util.component.ContainerLifeCycle
implements SessionCache
    AbstractSessionCache A base implementation of the SessionCache interface for managing a set of Session objects pertaining to a context in memory. This implementation ensures that multiple requests for the same session id always return the same Session object. It will delay writing out a session to the SessionDataStore until the last request exits the session. If the SessionDataStore supports passivation then the session passivation and activation listeners are called appropriately as the session is written. This implementation also supports evicting idle Session objects. An idle Session is one that is still valid, has not expired, but has not been accessed by a request for a configurable amount of time. An idle session will be first passivated before it is evicted from the cache.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      protected class  AbstractSessionCache.PlaceHolderSession
      PlaceHolder

      • Nested classes/interfaces inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

        org.eclipse.jetty.util.component.AbstractLifeCycle.AbstractLifeCycleListener

      • Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.Container

        org.eclipse.jetty.util.component.Container.InheritedListener, org.eclipse.jetty.util.component.Container.Listener

      • Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.LifeCycle

        org.eclipse.jetty.util.component.LifeCycle.Listener

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected SessionContext _context
      Information about the context to which this SessionCache pertains
      protected int _evictionPolicy
      When, if ever, to evict sessions: never; only when the last request for them finishes; after inactivity time (expressed as secs)
      protected SessionHandler _handler
      The SessionHandler related to this SessionCache
      protected boolean _removeUnloadableSessions
      If true, a Session whose data cannot be read will be deleted from the SessionDataStore.
      protected boolean _saveOnCreate
      If true, as soon as a new session is created, it will be persisted to the SessionDataStore
      protected boolean _saveOnInactiveEviction
      If true, a session that will be evicted from the cache because it has been inactive too long will be saved before being evicted.
      protected SessionDataStore _sessionDataStore
      The authoritative source of session data

      • Fields inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

        FAILED, RUNNING, STARTED, STARTING, STOPPED, STOPPING

      • Fields inherited from interface org.eclipse.jetty.util.component.Dumpable

        KEY

    • Field Detail

      • _sessionDataStore

        protected SessionDataStore _sessionDataStore
        The authoritative source of session data

      • _handler

        protected final SessionHandler _handler
        The SessionHandler related to this SessionCache

      • _context

        protected SessionContext _context
        Information about the context to which this SessionCache pertains

      • _evictionPolicy

        protected int _evictionPolicy
        When, if ever, to evict sessions: never; only when the last request for them finishes; after inactivity time (expressed as secs)

      • _saveOnCreate

        protected boolean _saveOnCreate
        If true, as soon as a new session is created, it will be persisted to the SessionDataStore

      • _saveOnInactiveEviction

        protected boolean _saveOnInactiveEviction
        If true, a session that will be evicted from the cache because it has been inactive too long will be saved before being evicted.

      • _removeUnloadableSessions

        protected boolean _removeUnloadableSessions
        If true, a Session whose data cannot be read will be deleted from the SessionDataStore.

    • Method Detail

      • newSession

        public abstract Session newSession​(SessionData data)
        Create a new Session object from pre-existing session data
        Specified by:
        newSession in interface SessionCache
        Parameters:
        data - the session data
        Returns:
        a new Session object

      • newSession

        public abstract Session newSession​(HttpServletRequest request,
                                   SessionData data)
        Create a new Session for a request.
        Parameters:
        request - the request
        data - the session data
        Returns:
        the new session

      • doGet

        public abstract Session doGet​(String id)
        Get the session matching the key
        Parameters:
        id - session id
        Returns:
        the Session object matching the id

      • doPutIfAbsent

        public abstract Session doPutIfAbsent​(String id,
                                      Session session)
        Put the session into the map if it wasn't already there
        Parameters:
        id - the identity of the session
        session - the session object
        Returns:
        null if the session wasn't already in the map, or the existing entry otherwise

      • doReplace

        public abstract boolean doReplace​(String id,
                                  Session oldValue,
                                  Session newValue)
        Replace the mapping from id to oldValue with newValue
        Parameters:
        id - the id
        oldValue - the old value
        newValue - the new value
        Returns:
        true if replacement was done

      • doDelete

        public abstract Session doDelete​(String id)
        Remove the session with this identity from the store
        Parameters:
        id - the id
        Returns:
        true if removed false otherwise

      • doStart

        protected void doStart()
                throws Exception
        Overrides:
        doStart in class org.eclipse.jetty.util.component.ContainerLifeCycle
        Throws:
        Exception
        See Also:
        AbstractLifeCycle.doStart()

      • doStop

        protected void doStop()
               throws Exception
        Overrides:
        doStop in class org.eclipse.jetty.util.component.ContainerLifeCycle
        Throws:
        Exception
        See Also:
        AbstractLifeCycle.doStop()

      • setEvictionPolicy

        public void setEvictionPolicy​(int evictionTimeout)
        -1 means we never evict inactive sessions. 0 means we evict a session after the last request for it exits >0 is the number of seconds after which we evict inactive sessions from the cache
        Specified by:
        setEvictionPolicy in interface SessionCache
        Parameters:
        evictionTimeout - -1 is never evict; 0 is evict-on-exit; and any other positive value is the time in seconds that a session can be idle before it can be evicted.
        See Also:
        SessionCache.setEvictionPolicy(int)

      • isSaveOnCreate

        @ManagedAttribute(value="immediately save new sessions",
                  readonly=true)
public boolean isSaveOnCreate()
        Specified by:
        isSaveOnCreate in interface SessionCache
        Returns:
        if true the newly created session will be saved immediately

      • setSaveOnCreate

        public void setSaveOnCreate​(boolean saveOnCreate)
        Description copied from interface: SessionCache
        Whether or not a session that is newly created should be immediately saved. If false, a session that is created and invalidated within a single request is never persisted.
        Specified by:
        setSaveOnCreate in interface SessionCache
        Parameters:
        saveOnCreate - true to immediately save the newly created session

      • isRemoveUnloadableSessions

        @ManagedAttribute(value="delete unreadable stored sessions",
                  readonly=true)
public boolean isRemoveUnloadableSessions()
        Specified by:
        isRemoveUnloadableSessions in interface SessionCache
        Returns:
        true if sessions that can't be loaded are deleted from the store

      • setRemoveUnloadableSessions

        public void setRemoveUnloadableSessions​(boolean removeUnloadableSessions)
        If a session's data cannot be loaded from the store without error, remove it from the persistent store.
        Specified by:
        setRemoveUnloadableSessions in interface SessionCache
        Parameters:
        removeUnloadableSessions - if true unloadable sessions will be removed from session store

      • get

        public Session get​(String id)
            throws Exception
        Get a session object. If the session object is not in this session store, try getting the data for it from a SessionDataStore associated with the session manager.
        Specified by:
        get in interface SessionCache
        Parameters:
        id - the session id
        Returns:
        the Session if one exists, null otherwise
        Throws:
        Exception - if any error occurred
        See Also:
        SessionCache.get(java.lang.String)

      • put

        public void put​(String id,
                Session session)
         throws Exception
        Put the Session object back into the session store. This should be called when a request exists the session. Only when the last simultaneous request exists the session will any action be taken. If there is a SessionDataStore write the session data through to it. If the SessionDataStore supports passivation, call the passivate/active listeners. If the evictionPolicy == SessionCache.EVICT_ON_SESSION_EXIT then after we have saved the session, we evict it from the cache.
        Specified by:
        put in interface SessionCache
        Parameters:
        id - the session id
        session - the current session object
        Throws:
        Exception - if any error occurred
        See Also:
        SessionCache.put(java.lang.String, org.eclipse.jetty.server.session.Session)

      • exists

        public boolean exists​(String id)
               throws Exception
        Check to see if a session corresponding to the id exists. This method will first check with the object store. If it doesn't exist in the object store (might be passivated etc), it will check with the data store.
        Specified by:
        exists in interface SessionCache
        Parameters:
        id - the session id
        Returns:
        true if the session exists, false otherwise
        Throws:
        Exception - the Exception
        See Also:
        SessionCache.exists(java.lang.String)

      • contains

        public boolean contains​(String id)
                 throws Exception
        Check to see if this cache contains an entry for the session corresponding to the session id.
        Specified by:
        contains in interface SessionCache
        Parameters:
        id - the session id
        Returns:
        true if a Session object matching the id is present in the cache, false otherwise
        Throws:
        Exception - if any error occurred
        See Also:
        SessionCache.contains(java.lang.String)

      • checkExpiration

        public Set<String> checkExpiration​(Set<String> candidates)
        Description copied from interface: SessionCache
        Check a list of session ids that belong to potentially expired sessions. The Session in the cache should be checked, but also the SessionDataStore, as that is the authoritative source of all session information.
        Specified by:
        checkExpiration in interface SessionCache
        Parameters:
        candidates - the session ids to check
        Returns:
        the set of session ids that have actually expired: this can be a superset of the original candidate list.
        See Also:
        SessionCache.checkExpiration(Set)

      • checkInactiveSession

        public void checkInactiveSession​(Session session)
        Check a session for being inactive and thus being able to be evicted, if eviction is enabled.
        Specified by:
        checkInactiveSession in interface SessionCache
        Parameters:
        session - session to check

      • isSaveOnInactiveEviction

        @ManagedAttribute(value="save sessions before evicting from cache",
                  readonly=true)
public boolean isSaveOnInactiveEviction()
        Whether we should save a session that has been inactive before we boot it from the cache.
        Specified by:
        isSaveOnInactiveEviction in interface SessionCache
        Returns:
        true if an inactive session will be saved before being evicted

      • toString

        public String toString()
        Overrides:
        toString in class org.eclipse.jetty.util.component.AbstractLifeCycle