Package org.apache.catalina

Interface Manager

All Known Subinterfaces:
ClusterManager
All Known Implementing Classes:
BackupManager, ClusterManagerBase, DeltaManager, ManagerBase, PersistentManager, PersistentManagerBase, StandardManager
public interface Manager
A Manager manages the pool of Sessions that are associated with a particular Context. Different Manager implementations may support value-added features such as the persistent storage of session data, as well as migrating sessions for distributable web applications.

In order for a Manager implementation to successfully operate with a Context implementation that implements reloading, it must obey the following constraints:

  • Must implement Lifecycle so that the Context can indicate that a restart is required.
  • Must allow a call to stop() to be followed by a call to start() on the same Manager instance.
Author:
Craig R. McClanahan

  • Method Details

    • getContext

      Context getContext()
      Get the Context with which this Manager is associated.
      Returns:
      The associated Context

    • setContext

      void setContext(Context context)
      Set the Context with which this Manager is associated. The Context must be set to a non-null value before the Manager is first used. Multiple calls to this method before first use are permitted. Once the Manager has been used, this method may not be used to change the Context (including setting a null value) that the Manager is associated with.
      Parameters:
      context - The newly associated Context

    • getSessionIdGenerator

      SessionIdGenerator getSessionIdGenerator()
      Returns:
      the session id generator

    • setSessionIdGenerator

      void setSessionIdGenerator(SessionIdGenerator sessionIdGenerator)
      Sets the session id generator
      Parameters:
      sessionIdGenerator - The session id generator

    • getSessionCounter

      long getSessionCounter()
      Returns the total number of sessions created by this manager, which is approximated as the number of active sessions plus the number of expired sessions.
      Returns:
      Total number of sessions created by this manager.

    • setSessionCounter

      @Deprecated void setSessionCounter(long sessionCounter)
      Deprecated.
      This will be removed in Tomcat 11
      Sets the total number of sessions created by this manager.
      Parameters:
      sessionCounter - Total number of sessions created by this manager.

    • getMaxActive

      int getMaxActive()
      Gets the maximum number of sessions that have been active at the same time.
      Returns:
      Maximum number of sessions that have been active at the same time

    • setMaxActive

      void setMaxActive(int maxActive)
      (Re)sets the maximum number of sessions that have been active at the same time.
      Parameters:
      maxActive - Maximum number of sessions that have been active at the same time.

    • getActiveSessions

      int getActiveSessions()
      Gets the number of currently active sessions.
      Returns:
      Number of currently active sessions

    • getExpiredSessions

      long getExpiredSessions()
      Gets the number of sessions that have expired.
      Returns:
      Number of sessions that have expired

    • setExpiredSessions

      void setExpiredSessions(long expiredSessions)
      Sets the number of sessions that have expired.
      Parameters:
      expiredSessions - Number of sessions that have expired

    • getRejectedSessions

      int getRejectedSessions()
      Gets the number of sessions that were not created because the maximum number of active sessions was reached.
      Returns:
      Number of rejected sessions

    • getSessionMaxAliveTime

      int getSessionMaxAliveTime()
      Gets the longest time (in seconds) that an expired session had been alive.
      Returns:
      Longest time (in seconds) that an expired session had been alive.

    • setSessionMaxAliveTime

      void setSessionMaxAliveTime(int sessionMaxAliveTime)
      Sets the longest time (in seconds) that an expired session had been alive.
      Parameters:
      sessionMaxAliveTime - Longest time (in seconds) that an expired session had been alive.

    • getSessionAverageAliveTime

      int getSessionAverageAliveTime()
      Gets the average time (in seconds) that expired sessions had been alive. This may be based on sample data.
      Returns:
      Average time (in seconds) that expired sessions had been alive.

    • getSessionCreateRate

      int getSessionCreateRate()
      Gets the current rate of session creation (in session per minute). This may be based on sample data.
      Returns:
      The current rate (in sessions per minute) of session creation

    • getSessionExpireRate

      int getSessionExpireRate()
      Gets the current rate of session expiration (in session per minute). This may be based on sample data
      Returns:
      The current rate (in sessions per minute) of session expiration

    • add

      void add(Session session)
      Add this Session to the set of active Sessions for this Manager.
      Parameters:
      session - Session to be added

    • addPropertyChangeListener

      void addPropertyChangeListener(PropertyChangeListener listener)
      Add a property change listener to this component.
      Parameters:
      listener - The listener to add

    • changeSessionId

      @Deprecated void changeSessionId(Session session)
      Deprecated.
      Use rotateSessionId(Session). Will be removed in Tomcat 10
      Change the session ID of the current session to a new randomly generated session ID.
      Parameters:
      session - The session to change the session ID for

    • rotateSessionId

      default String rotateSessionId(Session session)
      Change the session ID of the current session to a new randomly generated session ID.
      Parameters:
      session - The session to change the session ID for
      Returns:
      The new session ID

    • changeSessionId

      void changeSessionId(Session session, String newId)
      Change the session ID of the current session to a specified session ID.
      Parameters:
      session - The session to change the session ID for
      newId - new session ID

    • createEmptySession

      Session createEmptySession()
      Get a session from the recycled ones or create a new empty one. The PersistentManager manager does not need to create session data because it reads it from the Store.
      Returns:
      An empty Session object

    • createSession

      Session createSession(String sessionId)
      Construct and return a new session object, based on the default settings specified by this Manager's properties. The session id specified will be used as the session id. If a new session cannot be created for any reason, return null.
      Parameters:
      sessionId - The session id which should be used to create the new session; if null, the session id will be assigned by this method, and available via the getId() method of the returned session.
      Returns:
      An empty Session object with the given ID or a newly created session ID if none was specified
      Throws:
      IllegalStateException - if a new session cannot be instantiated for any reason

    • findSession

      Session findSession(String id) throws IOException
      Return the active Session, associated with this Manager, with the specified session id (if any); otherwise return null.
      Parameters:
      id - The session id for the session to be returned
      Returns:
      the request session or null if a session with the requested ID could not be found
      Throws:
      IllegalStateException - if a new session cannot be instantiated for any reason
      IOException - if an input/output error occurs while processing this request

    • findSessions

      Session[] findSessions()
      Return the set of active Sessions associated with this Manager. If this Manager has no active Sessions, a zero-length array is returned.
      Returns:
      All the currently active sessions managed by this manager

    • load

      void load() throws ClassNotFoundException, IOException
      Load any currently active sessions that were previously unloaded to the appropriate persistence mechanism, if any. If persistence is not supported, this method returns without doing anything.
      Throws:
      ClassNotFoundException - if a serialized class cannot be found during the reload
      IOException - if an input/output error occurs

    • remove

      void remove(Session session)
      Remove this Session from the active Sessions for this Manager.
      Parameters:
      session - Session to be removed

    • remove

      void remove(Session session, boolean update)
      Remove this Session from the active Sessions for this Manager.
      Parameters:
      session - Session to be removed
      update - Should the expiration statistics be updated

    • removePropertyChangeListener

      void removePropertyChangeListener(PropertyChangeListener listener)
      Remove a property change listener from this component.
      Parameters:
      listener - The listener to remove

    • unload

      void unload() throws IOException
      Save any currently active sessions in the appropriate persistence mechanism, if any. If persistence is not supported, this method returns without doing anything.
      Throws:
      IOException - if an input/output error occurs

    • backgroundProcess

      void backgroundProcess()
      This method will be invoked by the context/container on a periodic basis and allows the manager to implement a method that executes periodic tasks, such as expiring sessions etc.

    • willAttributeDistribute

      boolean willAttributeDistribute(String name, Object value)
      Would the Manager distribute the given session attribute? Manager implementations may provide additional configuration options to control which attributes are distributable.
      Parameters:
      name - The attribute name
      value - The attribute value
      Returns:
      true if the Manager would distribute the given attribute otherwise false

    • getNotifyBindingListenerOnUnchangedValue

      default boolean getNotifyBindingListenerOnUnchangedValue()
      When an attribute that is already present in the session is added again under the same name and the attribute implements HttpSessionBindingListener, should HttpSessionBindingListener.valueUnbound(javax.servlet.http.HttpSessionBindingEvent) be called followed by HttpSessionBindingListener.valueBound(javax.servlet.http.HttpSessionBindingEvent)?

      The default value is false.

      Returns:
      true if the listener will be notified, false if it will not

    • setNotifyBindingListenerOnUnchangedValue

      void setNotifyBindingListenerOnUnchangedValue(boolean notifyBindingListenerOnUnchangedValue)
      Configure if HttpSessionBindingListener.valueUnbound(javax.servlet.http.HttpSessionBindingEvent) be called followed by HttpSessionBindingListener.valueBound(javax.servlet.http.HttpSessionBindingEvent) when an attribute that is already present in the session is added again under the same name and the attribute implements HttpSessionBindingListener.
      Parameters:
      notifyBindingListenerOnUnchangedValue - true the listener will be called, false it will not

    • getNotifyAttributeListenerOnUnchangedValue

      default boolean getNotifyAttributeListenerOnUnchangedValue()
      When an attribute that is already present in the session is added again under the same name and a HttpSessionAttributeListener is configured for the session should HttpSessionAttributeListener.attributeReplaced(javax.servlet.http.HttpSessionBindingEvent) be called?

      The default value is true.

      Returns:
      true if the listener will be notified, false if it will not

    • setNotifyAttributeListenerOnUnchangedValue

      void setNotifyAttributeListenerOnUnchangedValue(boolean notifyAttributeListenerOnUnchangedValue)
      Configure if HttpSessionAttributeListener.attributeReplaced(javax.servlet.http.HttpSessionBindingEvent) when an attribute that is already present in the session is added again under the same name and a HttpSessionAttributeListener is configured for the session.
      Parameters:
      notifyAttributeListenerOnUnchangedValue - true the listener will be called, false it will not