deltasession.java

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        // Reset the instance variables associated with this Session
        attributes.clear();
        setAuthType(null);
        creationTime = 0L;
        expiring = false;
        id = null;
        lastAccessedTime = 0L;
        maxInactiveInterval = -1;
        accessCount = 0;
        notes.clear();
        setPrincipal(null);
        isNew = false;
        isValid = false;
        manager = null;
        deltaRequest.clear();
    }

    /**
     * Remove any object bound to the specified name in the internal notes for
     * this session.
     *
     * @param name
     *            Name of the note to be removed
     */
    public void removeNote(String name) {
        notes.remove(name);
    }

    /**
     * Remove a session event listener from this component.
     */
    public void removeSessionListener(SessionListener listener) {
        synchronized (listeners) {
            listeners.remove(listener);
        }
    }

    /**
     * Bind an object to a specified name in the internal notes associated with
     * this session, replacing any existing binding for this name.
     *
     * @param name
     *            Name to which the object should be bound
     * @param value
     *            Object to be bound to the specified name
     */
    public void setNote(String name, Object value) {
        notes.put(name, value);
    }

    /**
     * Return a string representation of this object.
     */
    public String toString() {
        StringBuffer sb = new StringBuffer();
        sb.append("DeltaSession[");
        sb.append(id);
        sb.append("]");
        return (sb.toString());
    }

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

    public synchronized void readExternal(ObjectInput in) throws IOException,ClassNotFoundException {
        readObjectData(in);
    }


    /**
     * Read a serialized version of the contents of this session object from the
     * specified object input stream, without requiring that the StandardSession
     * itself have been serialized.
     *
     * @param stream
     *            The object input stream to read from
     *
     * @exception ClassNotFoundException
     *                if an unknown class is specified
     * @exception IOException
     *                if an input/output error occurs
     */
    public void readObjectData(ObjectInput stream) throws ClassNotFoundException, IOException {
        readObject(stream);
    }

    /**
     * Write a serialized version of the contents of this session object to the
     * specified object output stream, without requiring that the
     * StandardSession itself have been serialized.
     *
     * @param stream
     *            The object output stream to write to
     *
     * @exception IOException
     *                if an input/output error occurs
     */
    public void writeObjectData(ObjectOutput stream) throws IOException {
        writeObject(stream);
    }

    public void resetDeltaRequest() {
        if (deltaRequest == null) {
            deltaRequest = new DeltaRequest(getIdInternal(), false);
        } else {
            deltaRequest.reset();
            deltaRequest.setSessionId(getIdInternal());
        }
    }

    public DeltaRequest getDeltaRequest() {
        if (deltaRequest == null) resetDeltaRequest();
        return deltaRequest;
    }

    // ------------------------------------------------- HttpSession Properties

    /**
     * Return the time when this session was created, in milliseconds since
     * midnight, January 1, 1970 GMT.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public long getCreationTime() {
        if (!expiring && !isValid)
            throw new IllegalStateException(sm.getString("standardSession.getCreationTime.ise"));
        return (this.creationTime);
    }

    /**
     * Return the ServletContext to which this session belongs.
     */
    public ServletContext getServletContext() {
        if (manager == null)
            return (null);
        Context context = (Context) manager.getContainer();
        if (context == null)
            return (null);
        else
            return (context.getServletContext());
    }

    /**
     * Return the session context with which this session is associated.
     *
     * @deprecated As of Version 2.1, this method is deprecated and has no
     *             replacement. It will be removed in a future version of the
     *             Java Servlet API.
     */
    public HttpSessionContext getSessionContext() {
        if (sessionContext == null)
            sessionContext = new StandardSessionContext();
        return (sessionContext);
    }

    // ----------------------------------------------HttpSession Public Methods

    /**
     * Return the object bound with the specified name in this session, or
     * <code>null</code> if no object is bound with that name.
     *
     * @param name
     *            Name of the attribute to be returned
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public Object getAttribute(String name) {
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.getAttribute.ise"));
        return (attributes.get(name));
    }

    /**
     * Return an <code>Enumeration</code> of <code>String</code> objects
     * containing the names of the objects bound to this session.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public Enumeration getAttributeNames() {
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.getAttributeNames.ise"));
        return (new Enumerator(attributes.keySet(), true));
    }

    /**
     * Return the object bound with the specified name in this session, or
     * <code>null</code> if no object is bound with that name.
     *
     * @param name
     *            Name of the value to be returned
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     *
     * @deprecated As of Version 2.2, this method is replaced by
     *             <code>getAttribute()</code>
     */
    public Object getValue(String name) {
        return (getAttribute(name));
    }

    /**
     * Return the set of names of objects bound to this session. If there are no
     * such objects, a zero-length array is returned.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     *
     * @deprecated As of Version 2.2, this method is replaced by
     *             <code>getAttributeNames()</code>
     */
    public String[] getValueNames() {
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.getValueNames.ise"));
        return (keys());
    }

    /**
     * Invalidates this session and unbinds any objects bound to it.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public void invalidate() {
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.invalidate.ise"));
        // Cause this session to expire
        expire();
    }

    /**
     * Return <code>true</code> if the client does not yet know about the
     * session, or if the client chooses not to join the session. For example,
     * if the server used only cookie-based sessions, and the client has
     * disabled the use of cookies, then a session would be new on each request.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public boolean isNew() {
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.isNew.ise"));
        return (this.isNew);
    }

    /**
     * Bind an object to this session, using the specified name. If an object of
     * the same name is already bound to this session, the object is replaced.
     * <p>
     * After this method executes, and if the object implements
     * <code>HttpSessionBindingListener</code>, the container calls
     * <code>valueBound()</code> on the object.
     *
     * @param name
     *            Name to which the object is bound, cannot be null
     * @param value
     *            Object to be bound, cannot be null
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     *
     * @deprecated As of Version 2.2, this method is replaced by
     *             <code>setAttribute()</code>
     */
    public void putValue(String name, Object value) {
        setAttribute(name, value);
    }

    /**
     * Remove the object bound with the specified name from this session. If the
     * session does not have an object bound with this name, this method does
     * nothing.
     * <p>
     * After this method executes, and if the object implements
     * <code>HttpSessionBindingListener</code>, the container calls
     * <code>valueUnbound()</code> on the object.
     *
     * @param name
     *            Name of the object to remove from this session.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public void removeAttribute(String name) {
        removeAttribute(name, true);
    }

    /**
     * Remove the object bound with the specified name from this session. If the
     * session does not have an object bound with this name, this method does
     * nothing.
     * <p>
     * After this method executes, and if the object implements
     * <code>HttpSessionBindingListener</code>, the container calls
     * <code>valueUnbound()</code> on the object.
     *
     * @param name
     *            Name of the object to remove from this session.
     * @param notify
     *            Should we notify interested listeners that this attribute is
     *            being removed?
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public void removeAttribute(String name, boolean notify) {
        removeAttribute(name, notify, true);
    }

    public void removeAttribute(String name, boolean notify,
                                boolean addDeltaRequest) {
        // Validate our current state
        if (!isValid())
            throw new IllegalStateException(sm.getString("standardSession.removeAttribute.ise"));
        removeAttributeInternal(name, notify, addDeltaRequest);
    }

    /**
     * Remove the object bound with the specified name from this session. If the
     * session does not have an object bound with this name, this method does
     * nothing.
     * <p>
     * After this method executes, and if the object implements
     * <code>HttpSessionBindingListener</code>, the container calls
     * <code>valueUnbound()</code> on the object.
     *
     * @param name
     *            Name of the object to remove from this session.
     *
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     *
     * @deprecated As of Version 2.2, this method is replaced by
     *             <code>removeAttribute()</code>
     */
    public void removeValue(String name) {
        removeAttribute(name);
    }

    /**
     * Bind an object to this session, using the specified name. If an object of
     * the same name is already bound to this session, the object is replaced.
     * <p>
     * After this method executes, and if the object implements
     * <code>HttpSessionBindingListener</code>, the container calls
     * <code>valueBound()</code> on the object.
     *
     * @param name
     *            Name to which the object is bound, cannot be null
     * @param value
     *            Object to be bound, cannot be null
     *
     * @exception IllegalArgumentException
     *                if an attempt is made to add a non-serializable object in
     *                an environment marked distributable.
     * @exception IllegalStateException
     *                if this method is called on an invalidated session
     */
    public void setAttribute(String name, Object value) {
        setAttribute(name, value, true, true);
    }

    public void setAttribute(String name, Object value, boolean notify,
                             boolean addDeltaRequest) {

        // Name cannot be null
        if (name == null)
            throw new IllegalArgumentException(sm.getString("standardSession.setAttribute.namenull"));

        // Null value is the same as removeAttribute()
        if (value == null) {
            removeAttribute(name);
            return;
        }

        try {
            lock();
            // Validate our current state
            if (!isValid())
                throw new IllegalStateException(sm.getString("standardSession.setAttribute.ise"));
            if (! (value instanceof java.io.Serializable)) {
                throw new IllegalArgumentException("Attribute [" + name + "] is not serializable");
            }

            if (addDeltaRequest && (deltaRequest != null))
                deltaRequest.setAttribute(name, value);

            // Construct an event with the new value
            HttpSessionBindingEvent event = null;

            // Call the valueBound() method if necessary
            if (value instanceof HttpSessionBindingListener && notify) {
                // Don't call any notification if replacing with the same value
                Object oldValue = attributes.get(name);
                if (value != oldValue) {
                    event = new HttpSessionBindingEvent(getSession(), name, value);
                    try {
                        ( (HttpSessionBindingListener) value).valueBound(event);
                    } catch (Exception x) {
                        log.error(sm.getString("deltaSession.valueBound.ex"), x);
                    }
                }
            }

            // Replace or add this attribute