jvmroutebindervalve.java

业界著名的tomcat服务器的最新6.0的源代码。

    
    /**
     * @param cluster The cluster to set.
     */
    public void setCluster(CatalinaCluster cluster) {
        this.cluster = cluster;
    }
    
    /**
     * Handle jvmRoute stickyness after tomcat instance failed. After this
     * correction a new Cookie send to client with new jvmRoute and the
     * SessionID change propage to the other cluster nodes.
     * 
     * @param request current request
     * @param response
     *            Tomcat Response
     * @param sessionId
     *            request SessionID from Cookie
     * @param localJvmRoute
     *            local jvmRoute
     */
    protected void handleJvmRoute(
            Request request, Response response,String sessionId, String localJvmRoute) {
        // get requested jvmRoute.
        String requestJvmRoute = null;
        int index = sessionId.indexOf(".");
        if (index > 0) {
            requestJvmRoute = sessionId
                    .substring(index + 1, sessionId.length());
        }
        if (requestJvmRoute != null && !requestJvmRoute.equals(localJvmRoute)) {
            if (log.isDebugEnabled()) {
                log.debug(sm.getString("jvmRoute.failover", requestJvmRoute,
                        localJvmRoute, sessionId));
            }
            // OK - turnover the session ?
            String newSessionID = sessionId.substring(0, index) + "."
                    + localJvmRoute;
            Session catalinaSession = null;
            try {
                catalinaSession = getManager(request).findSession(sessionId);
            } catch (IOException e) {
                // Hups!
            }
            if (catalinaSession != null) {
                changeSessionID(request, response, sessionId, newSessionID,
                        catalinaSession);
                numberOfSessions++;
            } else {
                if (log.isDebugEnabled()) {
                    log.debug(sm.getString("jvmRoute.cannotFindSession",
                            sessionId));
                }
            }
        }
    }

    /**
     * change session id and send to all cluster nodes
     * 
     * @param request current request
     * @param response current response
     * @param sessionId
     *            original session id
     * @param newSessionID
     *            new session id for node migration
     * @param catalinaSession
     *            current session with original session id
     */
    protected void changeSessionID(Request request,
            Response response, String sessionId, String newSessionID, Session catalinaSession) {
        lifecycle.fireLifecycleEvent("Before session migration",
                catalinaSession);
        request.setRequestedSessionId(newSessionID);
        catalinaSession.setId(newSessionID);
        if (catalinaSession instanceof DeltaSession)
            ((DeltaSession) catalinaSession).resetDeltaRequest();
        if(request.isRequestedSessionIdFromCookie()) setNewSessionCookie(request, response,newSessionID);
        // set orginal sessionid at request, to allow application detect the
        // change
        if (sessionIdAttribute != null && !"".equals(sessionIdAttribute)) {
            if (log.isDebugEnabled()) {
                log.debug(sm.getString("jvmRoute.set.orignalsessionid",sessionIdAttribute,sessionId));
            }
            request.setAttribute(sessionIdAttribute, sessionId);
        }
        // now sending the change to all other clusternode!
        ClusterManager manager = (ClusterManager)catalinaSession.getManager();
        sendSessionIDClusterBackup(manager,request,sessionId, newSessionID);
        lifecycle
                .fireLifecycleEvent("After session migration", catalinaSession);
        if (log.isDebugEnabled()) {
            log.debug(sm.getString("jvmRoute.changeSession", sessionId,
                    newSessionID));
        }
    }

    /**
     * Send the changed Sessionid to all clusternodes.
     * 
     * @see JvmRouteSessionIDBinderListener#messageReceived(ClusterMessage)
     * @param manager
     *            ClusterManager
     * @param sessionId
     *            current failed sessionid
     * @param newSessionID
     *            new session id, bind to the new cluster node
     */
    protected void sendSessionIDClusterBackup(ClusterManager manager,Request request,String sessionId,
            String newSessionID) {
        SessionIDMessage msg = new SessionIDMessage();
        msg.setOrignalSessionID(sessionId);
        msg.setBackupSessionID(newSessionID);
        Context context = request.getContext();
        msg.setContextPath(context.getPath());
        msg.setHost(context.getParent().getName());
        if(manager.doDomainReplication())
            cluster.sendClusterDomain(msg);
        else
            cluster.send(msg);
    }

    /**
     * Sets a new cookie for the given session id and response and see
     * {@link org.apache.catalina.connector.Request#configureSessionCookie(javax.servlet.http.Cookie)}
     * 
     * @param request current request
     * @param response Tomcat Response
     * @param sessionId The session id
     */
    protected void setNewSessionCookie(Request request,
                                       Response response, String sessionId) {
        if (response != null) {
            Context context = request.getContext();
            if (context.getCookies()) {
                // set a new session cookie
                Cookie newCookie = new Cookie(Globals.SESSION_COOKIE_NAME,
                        sessionId);
                newCookie.setMaxAge(-1);
                String contextPath = null;
                if (!response.getConnector().getEmptySessionPath()
                        && (context != null)) {
                    contextPath = context.getEncodedPath();
                }
                if ((contextPath != null) && (contextPath.length() > 0)) {
                    newCookie.setPath(contextPath);
                } else {
                    newCookie.setPath("/");
                }
                if (request.isSecure()) {
                    newCookie.setSecure(true);
                }
                if (log.isDebugEnabled()) {
                    log.debug(sm.getString("jvmRoute.newSessionCookie",
                            sessionId, Globals.SESSION_COOKIE_NAME, newCookie
                                    .getPath(), new Boolean(newCookie
                                    .getSecure())));
                }
                response.addCookie(newCookie);
            }
        }
    }

    // ------------------------------------------------------ Lifecycle Methods

    /**
     * Add a lifecycle event listener to this component.
     * 
     * @param listener
     *            The listener to add
     */
    public void addLifecycleListener(LifecycleListener listener) {

        lifecycle.addLifecycleListener(listener);

    }

    /**
     * Get the lifecycle listeners associated with this lifecycle. If this
     * Lifecycle has no listeners registered, a zero-length array is returned.
     */
    public LifecycleListener[] findLifecycleListeners() {

        return lifecycle.findLifecycleListeners();

    }

    /**
     * Remove a lifecycle event listener from this component.
     * 
     * @param listener
     *            The listener to add
     */
    public void removeLifecycleListener(LifecycleListener listener) {

        lifecycle.removeLifecycleListener(listener);

    }

    /**
     * Prepare for the beginning of active use of the public methods of this
     * component. This method should be called after <code>configure()</code>,
     * and before any of the public methods of the component are utilized.
     * 
     * @exception LifecycleException
     *                if this component detects a fatal error that prevents this
     *                component from being used
     */
    public void start() throws LifecycleException {

        // Validate and update our current component state
        if (started)
            throw new LifecycleException(sm
                    .getString("jvmRoute.valve.alreadyStarted"));
        lifecycle.fireLifecycleEvent(START_EVENT, null);
        started = true;
        if (cluster == null) {
            Container hostContainer = getContainer();
            // compatibility with JvmRouteBinderValve version 1.1
            // ( setup at context.xml or context.xml.default )
            if (!(hostContainer instanceof Host)) {
                if (log.isWarnEnabled())
                    log.warn(sm.getString("jvmRoute.configure.warn"));
                hostContainer = hostContainer.getParent();
            }
            if (hostContainer instanceof Host
                    && ((Host) hostContainer).getCluster() != null) {
                cluster = (CatalinaCluster) ((Host) hostContainer).getCluster();
            } else {
                Container engine = hostContainer.getParent() ;
                if (engine instanceof Engine
                        && ((Engine) engine).getCluster() != null) {
                    cluster = (CatalinaCluster) ((Engine) engine).getCluster();
                }
            }
        }
        if (cluster == null) {
            throw new RuntimeException("No clustering support at container "
                    + container.getName());
        }
        
        if (log.isInfoEnabled())
            log.info(sm.getString("jvmRoute.valve.started"));

    }

    /**
     * Gracefully terminate the active use of the public methods of this
     * component. This method should be the last one called on a given instance
     * of this component.
     * 
     * @exception LifecycleException
     *                if this component detects a fatal error that needs to be
     *                reported
     */
    public void stop() throws LifecycleException {

        // Validate and update our current component state
        if (!started)
            throw new LifecycleException(sm
                    .getString("jvmRoute.valve.notStarted"));
        lifecycle.fireLifecycleEvent(STOP_EVENT, null);
        started = false;
        cluster = null;
        numberOfSessions = 0;
        if (log.isInfoEnabled())
            log.info(sm.getString("jvmRoute.valve.stopped"));

    }

}