--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/eclipse/jetty/server/session/HashSessionManager.java	Wed Sep 07 21:15:48 2016 -0600
@@ -0,0 +1,640 @@
+//
+//  ========================================================================
+//  Copyright (c) 1995-2014 Mort Bay Consulting Pty. Ltd.
+//  ------------------------------------------------------------------------
+//  All rights reserved. This program and the accompanying materials
+//  are made available under the terms of the Eclipse Public License v1.0
+//  and Apache License v2.0 which accompanies this distribution.
+//
+//      The Eclipse Public License is available at
+//      http://www.eclipse.org/legal/epl-v10.html
+//
+//      The Apache License v2.0 is available at
+//      http://www.opensource.org/licenses/apache2.0.php
+//
+//  You may elect to redistribute this code under either of these licenses.
+//  ========================================================================
+//
+
+package org.eclipse.jetty.server.session;
+
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.ObjectInputStream;
+import java.net.URI;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Set;
+import java.util.Timer;
+import java.util.TimerTask;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+import javax.servlet.ServletContext;
+import javax.servlet.http.HttpServletRequest;
+
+import org.eclipse.jetty.server.handler.ContextHandler;
+import org.eclipse.jetty.util.IO;
+import org.eclipse.jetty.util.log.Logger;
+
+
+/* ------------------------------------------------------------ */
+/** 
+ * HashSessionManager
+ * 
+ * An in-memory implementation of SessionManager.
+ * <p>
+ * This manager supports saving sessions to disk, either periodically or at shutdown.
+ * Sessions can also have their content idle saved to disk to reduce the memory overheads of large idle sessions.
+ * <p>
+ * This manager will create it's own Timer instance to scavenge threads, unless it discovers a shared Timer instance
+ * set as the "org.eclipse.jetty.server.session.timer" attribute of the ContextHandler.
+ *
+ */
+public class HashSessionManager extends AbstractSessionManager
+{
+    final static Logger __log = SessionHandler.LOG;
+
+    protected final ConcurrentMap<String,HashedSession> _sessions=new ConcurrentHashMap<String,HashedSession>();
+    private static int __id;
+    private Timer _timer;
+    private boolean _timerStop=false;
+    private TimerTask _task;
+    long _scavengePeriodMs=30000;
+    long _savePeriodMs=0; //don't do period saves by default
+    long _idleSavePeriodMs = 0; // don't idle save sessions by default.
+    private TimerTask _saveTask;
+    File _storeDir;
+    private boolean _lazyLoad=false;
+    private volatile boolean _sessionsLoaded=false;
+    private boolean _deleteUnrestorableSessions=false;
+    
+
+
+
+    /* ------------------------------------------------------------ */
+    public HashSessionManager()
+    {
+        super();
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @see org.eclipse.jetty.servlet.AbstractSessionManager#doStart()
+     */
+    @Override
+    public void doStart() throws Exception
+    {
+        super.doStart();
+
+        _timerStop=false;
+        ServletContext context = ContextHandler.getCurrentContext();
+        if (context!=null)
+            _timer=(Timer)context.getAttribute("org.eclipse.jetty.server.session.timer");
+        if (_timer==null)
+        {
+            _timerStop=true;
+            _timer=new Timer("HashSessionScavenger-"+__id++, true);
+        }
+
+        setScavengePeriod(getScavengePeriod());
+
+        if (_storeDir!=null)
+        {
+            if (!_storeDir.exists())
+                _storeDir.mkdirs();
+
+            if (!_lazyLoad)
+                restoreSessions();
+        }
+
+        setSavePeriod(getSavePeriod());
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @see org.eclipse.jetty.servlet.AbstractSessionManager#doStop()
+     */
+    @Override
+    public void doStop() throws Exception
+    {
+        // stop the scavengers
+        synchronized(this)
+        {
+            if (_saveTask!=null)
+                _saveTask.cancel();
+            _saveTask=null;
+            if (_task!=null)
+                _task.cancel();
+            _task=null;
+            if (_timer!=null && _timerStop)
+                _timer.cancel();
+            _timer=null;
+        }
+
+        // This will callback invalidate sessions - where we decide if we will save
+        super.doStop();
+
+        _sessions.clear();
+
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return the period in seconds at which a check is made for sessions to be invalidated.
+     */
+    public int getScavengePeriod()
+    {
+        return (int)(_scavengePeriodMs/1000);
+    }
+
+
+    /* ------------------------------------------------------------ */
+    @Override
+    public int getSessions()
+    {
+        int sessions=super.getSessions();
+        if (__log.isDebugEnabled())
+        {
+            if (_sessions.size()!=sessions)
+                __log.warn("sessions: "+_sessions.size()+"!="+sessions);
+        }
+        return sessions;
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return seconds Idle period after which a session is saved
+     */
+    public int getIdleSavePeriod()
+    {
+      if (_idleSavePeriodMs <= 0)
+        return 0;
+
+      return (int)(_idleSavePeriodMs / 1000);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * Configures the period in seconds after which a session is deemed idle and saved
+     * to save on session memory.
+     *
+     * The session is persisted, the values attribute map is cleared and the session set to idled.
+     *
+     * @param seconds Idle period after which a session is saved
+     */
+    public void setIdleSavePeriod(int seconds)
+    {
+      _idleSavePeriodMs = seconds * 1000L;
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    public void setMaxInactiveInterval(int seconds)
+    {
+        super.setMaxInactiveInterval(seconds);
+        if (_dftMaxIdleSecs>0&&_scavengePeriodMs>_dftMaxIdleSecs*1000L)
+            setScavengePeriod((_dftMaxIdleSecs+9)/10);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @param seconds the period is seconds at which sessions are periodically saved to disk
+     */
+    public void setSavePeriod (int seconds)
+    {
+        long period = (seconds * 1000L);
+        if (period < 0)
+            period=0;
+        _savePeriodMs=period;
+
+        if (_timer!=null)
+        {
+            synchronized (this)
+            {
+                if (_saveTask!=null)
+                    _saveTask.cancel();
+                if (_savePeriodMs > 0 && _storeDir!=null) //only save if we have a directory configured
+                {
+                    _saveTask = new TimerTask()
+                    {
+                        @Override
+                        public void run()
+                        {
+                            try
+                            {
+                                saveSessions(true);
+                            }
+                            catch (Exception e)
+                            {
+                                __log.warn(e);
+                            }
+                        }
+                    };
+                    _timer.schedule(_saveTask,_savePeriodMs,_savePeriodMs);
+                }
+            }
+        }
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @return the period in seconds at which sessions are periodically saved to disk
+     */
+    public int getSavePeriod ()
+    {
+        if (_savePeriodMs<=0)
+            return 0;
+
+        return (int)(_savePeriodMs/1000);
+    }
+
+    /* ------------------------------------------------------------ */
+    /**
+     * @param seconds the period in seconds at which a check is made for sessions to be invalidated.
+     */
+    public void setScavengePeriod(int seconds)
+    { 
+        if (seconds==0)
+            seconds=60;
+
+        long old_period=_scavengePeriodMs;
+        long period=seconds*1000L;
+        if (period>60000)
+            period=60000;
+        if (period<1000)
+            period=1000;
+
+        _scavengePeriodMs=period;
+    
+        if (_timer!=null && (period!=old_period || _task==null))
+        {
+            synchronized (this)
+            {
+                if (_task!=null)
+                    _task.cancel();
+                _task = new TimerTask()
+                {
+                    @Override
+                    public void run()
+                    {
+                        scavenge();
+                    }
+                };
+                _timer.schedule(_task,_scavengePeriodMs,_scavengePeriodMs);
+            }
+        }
+    }
+
+    /* -------------------------------------------------------------- */
+    /**
+     * Find sessions that have timed out and invalidate them. This runs in the
+     * SessionScavenger thread.
+     */
+    protected void scavenge()
+    {
+        //don't attempt to scavenge if we are shutting down
+        if (isStopping() || isStopped())
+            return;
+
+        Thread thread=Thread.currentThread();
+        ClassLoader old_loader=thread.getContextClassLoader();
+        try
+        {
+            if (_loader!=null)
+                thread.setContextClassLoader(_loader);
+
+            // For each session
+            long now=System.currentTimeMillis();
+          
+            for (Iterator<HashedSession> i=_sessions.values().iterator(); i.hasNext();)
+            {
+                HashedSession session=i.next();
+                long idleTime=session.getMaxInactiveInterval()*1000L; 
+                if (idleTime>0&&session.getAccessed()+idleTime<now)
+                {
+                    // Found a stale session, add it to the list
+                    try
+                    {
+                        session.timeout();
+                    }
+                    catch (Exception e)
+                    {
+                        __log.warn("Problem scavenging sessions", e);
+                    }
+                }
+                else if (_idleSavePeriodMs > 0 && session.getAccessed()+_idleSavePeriodMs < now)
+                {
+                    try
+                    {
+                        session.idle();
+                    }
+                    catch (Exception e)
+                    {
+                        __log.warn("Problem idling session "+ session.getId(), e);
+                    }
+                }
+            }
+        }       
+        finally
+        {
+            thread.setContextClassLoader(old_loader);
+        }
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    protected void addSession(AbstractSession session)
+    {
+        if (isRunning())
+            _sessions.put(session.getClusterId(),(HashedSession)session);
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    public AbstractSession getSession(String idInCluster)
+    {
+        if ( _lazyLoad && !_sessionsLoaded)
+        {
+            try
+            {
+                restoreSessions();
+            }
+            catch(Exception e)
+            {
+                __log.warn(e);
+            }
+        }
+
+        Map<String,HashedSession> sessions=_sessions;
+        if (sessions==null)
+            return null;
+
+        HashedSession session = sessions.get(idInCluster);
+
+        if (session == null && _lazyLoad)
+            session=restoreSession(idInCluster);
+        if (session == null)
+            return null;
+
+        if (_idleSavePeriodMs!=0)
+            session.deIdle();
+
+        return session;
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    protected void invalidateSessions() throws Exception
+    {
+        // Invalidate all sessions to cause unbind events
+        ArrayList<HashedSession> sessions=new ArrayList<HashedSession>(_sessions.values());
+        int loop=100;
+        while (sessions.size()>0 && loop-->0)
+        {
+            // If we are called from doStop
+            if (isStopping() && _storeDir != null && _storeDir.exists() && _storeDir.canWrite())
+            {
+                // Then we only save and remove the session - it is not invalidated.
+                for (HashedSession session : sessions)
+                {
+                    session.save(false);
+                    removeSession(session,false);
+                }
+            }
+            else
+            {
+                for (HashedSession session : sessions)
+                    session.invalidate();
+            }
+
+            // check that no new sessions were created while we were iterating
+            sessions=new ArrayList<HashedSession>(_sessions.values());
+        }
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    protected AbstractSession newSession(HttpServletRequest request)
+    {
+        return new HashedSession(this, request);
+    }
+
+    /* ------------------------------------------------------------ */
+    protected AbstractSession newSession(long created, long accessed, String clusterId)
+    {
+        return new HashedSession(this, created,accessed, clusterId);
+    }
+
+    /* ------------------------------------------------------------ */
+    @Override
+    protected boolean removeSession(String clusterId)
+    {
+        return _sessions.remove(clusterId)!=null;
+    }
+
+    /* ------------------------------------------------------------ */
+    public void setStoreDirectory (File dir) throws IOException
+    { 
+        // CanonicalFile is used to capture the base store directory in a way that will
+        // work on Windows.  Case differences may through off later checks using this directory.
+        _storeDir=dir.getCanonicalFile();
+    }
+
+    /* ------------------------------------------------------------ */
+    public File getStoreDirectory ()
+    {
+        return _storeDir;
+    }
+
+    /* ------------------------------------------------------------ */
+    public void setLazyLoad(boolean lazyLoad)
+    {
+        _lazyLoad = lazyLoad;
+    }
+
+    /* ------------------------------------------------------------ */
+    public boolean isLazyLoad()
+    {
+        return _lazyLoad;
+    }
+    
+    /* ------------------------------------------------------------ */
+    public boolean isDeleteUnrestorableSessions()
+    {
+        return _deleteUnrestorableSessions;
+    }
+    
+    /* ------------------------------------------------------------ */
+    public void setDeleteUnrestorableSessions(boolean deleteUnrestorableSessions)
+    {
+        _deleteUnrestorableSessions = deleteUnrestorableSessions;
+    }
+
+    /* ------------------------------------------------------------ */
+    public void restoreSessions () throws Exception
+    {
+        _sessionsLoaded = true;
+
+        if (_storeDir==null || !_storeDir.exists())
+        {
+            return;
+        }
+
+        if (!_storeDir.canRead())
+        {
+            __log.warn ("Unable to restore Sessions: Cannot read from Session storage directory "+_storeDir.getAbsolutePath());
+            return;
+        }
+
+        String[] files = _storeDir.list();
+        for (int i=0;files!=null&&i<files.length;i++)
+        {
+            restoreSession(files[i]);
+        }
+    }
+
+    /* ------------------------------------------------------------ */
+    protected synchronized HashedSession restoreSession(String idInCuster)
+    {        
+        File file = new File(_storeDir,idInCuster);
+
+        FileInputStream in = null;
+        Exception error = null;
+        try
+        {
+            if (file.exists())
+            {
+                in = new FileInputStream(file);
+                HashedSession session = restoreSession(in, null);
+                addSession(session, false);
+                session.didActivate();
+                return session;
+            }
+        }
+        catch (Exception e)
+        {
+           error = e;
+        }
+        finally
+        {
+            if (in != null) IO.close(in);
+            
+            if (error != null)
+            {
+                if (isDeleteUnrestorableSessions() && file.exists() && file.getParentFile().equals(_storeDir) )
+                {
+                    file.delete();
+                    __log.warn("Deleting file for unrestorable session "+idInCuster, error);
+                }
+                else
+                {
+                    __log.warn("Problem restoring session "+idInCuster, error);
+                }
+            }
+            else
+               file.delete(); //delete successfully restored file
+                
+        }
+        return null;
+    }
+
+    /* ------------------------------------------------------------ */
+    public void saveSessions(boolean reactivate) throws Exception
+    {
+        if (_storeDir==null || !_storeDir.exists())
+        {
+            return;
+        }
+
+        if (!_storeDir.canWrite())
+        {
+            __log.warn ("Unable to save Sessions: Session persistence storage directory "+_storeDir.getAbsolutePath()+ " is not writeable");
+            return;
+        }
+
+        for (HashedSession session : _sessions.values())
+            session.save(true);
+    }
+
+    /* ------------------------------------------------------------ */
+    public HashedSession restoreSession (InputStream is, HashedSession session) throws Exception
+    {
+        /*
+         * Take care of this class's fields first by calling
+         * defaultReadObject
+         */
+        DataInputStream in = new DataInputStream(is);
+        try
+        {
+            String clusterId = in.readUTF();
+            in.readUTF(); // nodeId
+            long created = in.readLong();
+            long accessed = in.readLong();
+            int requests = in.readInt();
+
+            if (session == null)
+                session = (HashedSession)newSession(created, accessed, clusterId);
+            session.setRequests(requests);
+            int size = in.readInt();
+            if (size>0)
+            {
+                ClassLoadingObjectInputStream ois = new ClassLoadingObjectInputStream(in);
+                try
+                {
+                    for (int i=0; i<size;i++)
+                    {
+                        String key = ois.readUTF();
+                        Object value = ois.readObject();
+                        session.setAttribute(key,value);
+                    }
+                }
+                finally
+                {
+                    IO.close(ois);
+                }
+            }
+            return session;
+        }
+        finally
+        {
+            IO.close(in);
+        }
+    }
+
+
+    /* ------------------------------------------------------------ */
+    /* ------------------------------------------------------------ */
+    protected class ClassLoadingObjectInputStream extends ObjectInputStream
+    {
+        /* ------------------------------------------------------------ */
+        public ClassLoadingObjectInputStream(java.io.InputStream in) throws IOException
+        {
+            super(in);
+        }
+
+        /* ------------------------------------------------------------ */
+        public ClassLoadingObjectInputStream () throws IOException
+        {
+            super();
+        }
+
+        /* ------------------------------------------------------------ */
+        @Override
+        public Class<?> resolveClass (java.io.ObjectStreamClass cl) throws IOException, ClassNotFoundException
+        {
+            try
+            {
+                return Class.forName(cl.getName(), false, Thread.currentThread().getContextClassLoader());
+            }
+            catch (ClassNotFoundException e)
+            {
+                return super.resolveClass(cl);
+            }
+        }
+    }
+}