managerbase.java

业界著名的tomcat服务器的最新6.0的源代码。

    /**
     * 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.
     */
    public Session createEmptySession() {
        return (getNewSession());
    }


    /**
     * Return the active Session, associated with this Manager, with the
     * specified session id (if any); otherwise return <code>null</code>.
     *
     * @param id The session id for the session to be returned
     *
     * @exception IllegalStateException if a new session cannot be
     *  instantiated for any reason
     * @exception IOException if an input/output error occurs while
     *  processing this request
     */
    public Session findSession(String id) throws IOException {

        if (id == null)
            return (null);
        return (Session) sessions.get(id);

    }


    /**
     * Return the set of active Sessions associated with this Manager.
     * If this Manager has no active Sessions, a zero-length array is returned.
     */
    public Session[] findSessions() {

        Session results[] = null;
        synchronized (sessions) {
            results = new Session[sessions.size()];
            results = (Session[]) sessions.values().toArray(results);
        }
        return (results);

    }


    /**
     * Remove this Session from the active Sessions for this Manager.
     *
     * @param session Session to be removed
     */
    public void remove(Session session) {

        sessions.remove(session.getIdInternal());

    }


    /**
     * Remove a property change listener from this component.
     *
     * @param listener The listener to remove
     */
    public void removePropertyChangeListener(PropertyChangeListener listener) {

        support.removePropertyChangeListener(listener);

    }


    // ------------------------------------------------------ Protected Methods


    /**
     * Get new session class to be used in the doLoad() method.
     */
    protected StandardSession getNewSession() {
        return new StandardSession(this);
    }


    protected void getRandomBytes(byte bytes[]) {
        // Generate a byte array containing a session identifier
        if (devRandomSource != null && randomIS == null) {
            setRandomFile(devRandomSource);
        }
        if (randomIS != null) {
            try {
                int len = randomIS.read(bytes);
                if (len == bytes.length) {
                    return;
                }
                if(log.isDebugEnabled())
                    log.debug("Got " + len + " " + bytes.length );
            } catch (Exception ex) {
                // Ignore
            }
            devRandomSource = null;
            
            try {
                randomIS.close();
            } catch (Exception e) {
                log.warn("Failed to close randomIS.");
            }
            
            randomIS = null;
        }
        getRandom().nextBytes(bytes);
    }


    /**
     * Generate and return a new session identifier.
     */
    protected synchronized String generateSessionId() {

        byte random[] = new byte[16];
        String jvmRoute = getJvmRoute();
        String result = null;

        // Render the result as a String of hexadecimal digits
        StringBuffer buffer = new StringBuffer();
        do {
            int resultLenBytes = 0;
            if (result != null) {
                buffer = new StringBuffer();
                duplicates++;
            }

            while (resultLenBytes < this.sessionIdLength) {
                getRandomBytes(random);
                random = getDigest().digest(random);
                for (int j = 0;
                j < random.length && resultLenBytes < this.sessionIdLength;
                j++) {
                    byte b1 = (byte) ((random[j] & 0xf0) >> 4);
                    byte b2 = (byte) (random[j] & 0x0f);
                    if (b1 < 10)
                        buffer.append((char) ('0' + b1));
                    else
                        buffer.append((char) ('A' + (b1 - 10)));
                    if (b2 < 10)
                        buffer.append((char) ('0' + b2));
                    else
                        buffer.append((char) ('A' + (b2 - 10)));
                    resultLenBytes++;
                }
            }
            if (jvmRoute != null) {
                buffer.append('.').append(jvmRoute);
            }
            result = buffer.toString();
        } while (sessions.containsKey(result));
        return (result);

    }


    // ------------------------------------------------------ Protected Methods


    /**
     * Retrieve the enclosing Engine for this Manager.
     *
     * @return an Engine object (or null).
     */
    public Engine getEngine() {
        Engine e = null;
        for (Container c = getContainer(); e == null && c != null ; c = c.getParent()) {
            if (c != null && c instanceof Engine) {
                e = (Engine)c;
            }
        }
        return e;
    }


    /**
     * Retrieve the JvmRoute for the enclosing Engine.
     * @return the JvmRoute or null.
     */
    public String getJvmRoute() {
        Engine e = getEngine();
        return e == null ? null : e.getJvmRoute();
    }


    // -------------------------------------------------------- Package Methods


    public void setSessionCounter(int sessionCounter) {
        this.sessionCounter = sessionCounter;
    }


    /** 
     * Total sessions created by this manager.
     *
     * @return sessions created
     */
    public int getSessionCounter() {
        return sessionCounter;
    }


    /** 
     * Number of duplicated session IDs generated by the random source.
     * Anything bigger than 0 means problems.
     *
     * @return The count of duplicates
     */
    public int getDuplicates() {
        return duplicates;
    }


    public void setDuplicates(int duplicates) {
        this.duplicates = duplicates;
    }


    /** 
     * Returns the number of active sessions
     *
     * @return number of sessions active
     */
    public int getActiveSessions() {
        return sessions.size();
    }


    /**
     * Max number of concurrent active sessions
     *
     * @return The highest number of concurrent active sessions
     */
    public int getMaxActive() {
        return maxActive;
    }


    public void setMaxActive(int maxActive) {
        this.maxActive = maxActive;
    }


    /**
     * Gets the longest time (in seconds) that an expired session had been
     * alive.
     *
     * @return Longest time (in seconds) that an expired session had been
     * alive.
     */
    public int getSessionMaxAliveTime() {
        return sessionMaxAliveTime;
    }


    /**
     * Sets the longest time (in seconds) that an expired session had been
     * alive.
     *
     * @param sessionMaxAliveTime Longest time (in seconds) that an expired
     * session had been alive.
     */
    public void setSessionMaxAliveTime(int sessionMaxAliveTime) {
        this.sessionMaxAliveTime = sessionMaxAliveTime;
    }


    /**
     * Gets the average time (in seconds) that expired sessions had been
     * alive.
     *
     * @return Average time (in seconds) that expired sessions had been
     * alive.
     */
    public int getSessionAverageAliveTime() {
        return sessionAverageAliveTime;
    }


    /**
     * Sets the average time (in seconds) that expired sessions had been
     * alive.
     *
     * @param sessionAverageAliveTime Average time (in seconds) that expired
     * sessions had been alive.
     */
    public void setSessionAverageAliveTime(int sessionAverageAliveTime) {
        this.sessionAverageAliveTime = sessionAverageAliveTime;
    }


    /** 
     * For debugging: return a list of all session ids currently active
     *
     */
    public String listSessionIds() {
        StringBuffer sb=new StringBuffer();
        Iterator keys = sessions.keySet().iterator();
        while (keys.hasNext()) {
            sb.append(keys.next()).append(" ");
        }
        return sb.toString();
    }


    /** 
     * For debugging: get a session attribute
     *
     * @param sessionId
     * @param key
     * @return The attribute value, if found, null otherwise
     */
    public String getSessionAttribute( String sessionId, String key ) {
        Session s = (Session) sessions.get(sessionId);
        if( s==null ) {
            if(log.isInfoEnabled())
                log.info("Session not found " + sessionId);
            return null;
        }
        Object o=s.getSession().getAttribute(key);
        if( o==null ) return null;
        return o.toString();
    }


    /**
     * Returns information about the session with the given session id.
     * 
     * <p>The session information is organized as a HashMap, mapping 
     * session attribute names to the String representation of their values.
     *
     * @param sessionId Session id
     * 
     * @return HashMap mapping session attribute names to the String
     * representation of their values, or null if no session with the
     * specified id exists, or if the session does not have any attributes
     */
    public HashMap getSession(String sessionId) {
        Session s = (Session) sessions.get(sessionId);
        if (s == null) {
            if (log.isInfoEnabled()) {
                log.info("Session not found " + sessionId);
            }
            return null;
        }

        Enumeration ee = s.getSession().getAttributeNames();
        if (ee == null || !ee.hasMoreElements()) {
            return null;
        }

        HashMap map = new HashMap();
        while (ee.hasMoreElements()) {
            String attrName = (String) ee.nextElement();
            map.put(attrName, getSessionAttribute(sessionId, attrName));
        }

        return map;
    }


    public void expireSession( String sessionId ) {
        Session s=(Session)sessions.get(sessionId);
        if( s==null ) {
            if(log.isInfoEnabled())
                log.info("Session not found " + sessionId);
            return;
        }
        s.expire();
    }


    public String getLastAccessedTime( String sessionId ) {
        Session s=(Session)sessions.get(sessionId);
        if( s==null ) {
            log.info("Session not found " + sessionId);
            return "";
        }
        return new Date(s.getLastAccessedTime()).toString();
    }


    // -------------------- JMX and Registration  --------------------
    protected String domain;
    protected ObjectName oname;
    protected MBeanServer mserver;

    public ObjectName getObjectName() {
        return oname;
    }

    public String getDomain() {
        return domain;
    }

    public ObjectName preRegister(MBeanServer server,
                                  ObjectName name) throws Exception {
        oname=name;
        mserver=server;
        domain=name.getDomain();
        return name;
    }

    public void postRegister(Boolean registrationDone) {
    }

    public void preDeregister() throws Exception {
    }

    public void postDeregister() {
    }

}