Aranea distribution includes some third party Javascript libraries. Most of these are not needed for using Aranea functionality, but extend the functionality of both framework and UiLib.

Aranea uses javascript to do form submits. The code is sent to the client-side in compressed form. The script enables AJAX enabled webapps and provides more control over form submitting logic. Each page served by Aranea has associated AraneaPage object:

/**
 *  Exactly one AraneaPage object is present on each page served by Aranea and
 *  contains common functionality for setting page related variables, events and
 *  functions.
 */

// Servlet URL is set on every page load.
araneaPage().getServletURL();
araneaPage().setServletURL(url);

// If servlet URL is not enough for some purposes, encoding function should be overwritten.
araneaPage().encodeURL(url)

// Indicates whether the page is completely loaded or not. Page is considered to
// be loaded when all system onload events have completed execution.
araneaPage().isLoaded()
araneaPage().setLoaded(b)

// Dummy logger is practically no logger.
araneaPage().setDummyLogger()

// Makes Aranea scripts use log4javascript logger.
araneaPage().setDefaultLogger()

// Makes Aranea scripts use Firebug logger.
araneaPage().setFirebugLogger()

araneaPage().setLogger(theLogger)
araneaPage().getLogger()

// locale - should be used only for server-side reported locale.
araneaPage().getLocale()
araneaPage().setLocale(locale)

// Indicates whether some form on page is (being) submitted already
// by traditional HTTP request.
araneaPage().isSubmitted()
araneaPage().setSubmitted()

// Returns the active system form in this AraneaPage
araneaPage().getSystemForm()

araneaPage().setSystemForm(_systemForm)
araneaPage().setSystemFormEncoding(encoding)

// Returns the path of the component who should receive events generated by DOM element.
araneaPage().getEventTarget(element)

// Returns event id that should be sent to server when event(element) is called.
araneaPage().getEventId(element) {

// Returns event parameter that should be sent to server when event(element) is called.
araneaPage().getEventParam(element)

// Returns update regions that should be sent to server when event(element) is called.
araneaPage().getEventUpdateRegions(element)

// Returns closure that should be evaluated when event(element) is called and
// needs to decide whether server-side event invocation is needed.
araneaPage().getEventPreCondition(element)

// Adds a load event listener that is executed once when the page loaded.
araneaPage().addSystemLoadEvent(event)

// Adds a load event listener that is executed once when the page or part of it is loaded.
araneaPage().addClientLoadEvent(event)

// Adds a unload event listener that is executed once when the page unloaded.
araneaPage().addSystemUnLoadEvent(event)

araneaPage().onload()
araneaPage().onunload()

// Adds callback executed before next form submit. */
araneaPage().addSubmitCallback(callback)

// Add callback executed before form with given id is submitted next time.
araneaPage().addSystemFormSubmitCallback(systemFormId, callback) {

// Executes all callbacks that should run before submitting the form with given id.
// Executed callbacks are removed.
araneaPage().executeCallbacks(systemFormId)

// Chooses appropriate submitting method and submittable form given the HTML element
// that initiated the submit request. Applies the appropriate parameter values
// and submits the systemForm which owns the element.
araneaPage().event(element)

// Returns either form submitter, AJAX submitter, or overlay submitter.
// This function can be overwritten to support additional submit methods.
// It is called by event() to determine the appropriate form submitter.
araneaPage().findSubmitter(element, systemForm)

// Another submit function, takes all params that are possible to use with Aranea JSP currently.
araneaPage().event_6(systemForm, eventId, eventTarget, eventParam, eventPrecondition, eventUpdateRegions)

// Returns URL that can be used to invoke full HTTP request with some predefined request parameters.
araneaPage().getSubmitURL(topServiceId, threadServiceId, araTransactionId, extraParams)

// Returns URL that can be used to make server-side action-invoking
// XMLHttpRequest with some predefined request parameters.
araneaPage().getActionSubmitURL(systemForm, actionId, actionTarget, actionParam, sync, extraParams)

// Invokes server-side action listener by performing XMLHttpRequest with correct parameters.
araneaPage().action(element, actionId, actionTarget, actionParam, actionCallback, options, sync, extraParams)

// Invokes server-side action listener by performing XMLHttpRequest with correct parameters.
araneaPage().action_6(systemForm, actionId, actionTarget, actionParam, actionCallback, options, sync, extraParams)

// Method to log a message at DEBUG level.
// A shortcut for araneaPage().getLogger().debug(message).
araneaPage().debug(message)

// Adds keepalive function f that is executed periodically after time milliseconds has passed.
araneaPage().addKeepAlive: function(f, time)

// Clears/removes all registered keepalive functions.
araneaPage().clearKeepAlives()

// Returns the flag that determines whether background validation is used by
// for all forms (FormWidgets) in the application.
araneaPage().getBackgroundValidation()

// Proivdes a way to turn on/off background validation. The parameter is a boolean.
araneaPage().setBackgroundValidation(useAjax)

// ============================================================================
//                           STATIC METHODS
// ============================================================================

// Returns a default keepalive function -- to make periodical requests to
// expiring thread or top level services.
AraneaPage.getDefaultKeepAlive(topServiceId, threadServiceId, keepAliveKey)

// Searches for widget marker around the given element. If found, returns the
// marker DOM element, else returns null.
AraneaPage.findWidgetMarker(element)

// Random request ID generator. Sent only with XMLHttpRequests which apply to
// certain update regions. Currently its only purpose is easier debugging
// (identifying requests).
AraneaPage.getRandomRequestId()

// Returns the full URL for importing given file.
// The same URL that <ui:importScripts> outputs.
AraneaPage.getFileImportString(filename)

// Page initialization function, it is called upon page load.
AraneaPage.init()

// Page deinitialization function, it is called upon page unload.
AraneaPage.deinit()

// Searches for system form in HTML page and registers it in the current
// AraneaPage object as active systemForm. Also returns the found form.
AraneaPage.findSystemForm()

// RSH initialization for state versioning. Has effect only when "aranea-rsh.js"
// is also included in the page.
AraneaPage.initRSHURL()

// Properties for loading message:
AraneaPage.loadingMessageContent: 'Loading...',
AraneaPage.loadingMessageId: 'aranea-loading-message',
AraneaPage.reloadOnNoDocumentRegions: false,

// Add a handler that is invoked for custom data region in updateregions AJAX
// request. process() function will be invoked on the handler
// during processing the response. Data specific to this handler will be
// passed as the first parameter to that function (String).
AraneaPage.addRegionHandler(key, handler)

// Process response of an updateregions AJAX request. Should be called only
// on successful response. Invokes registered region handlers.
AraneaPage.processResponse(responseText)

AraneaPage.handleRequestException(request, exception)

// Create or show loading message at the top corner of the document. Called
// before initiating an updateregions Ajax.Request.
AraneaPage.showLoadingMessage()

// Hide loading message. Called after the completion of updateregions Ajax.Request.
AraneaPage.hideLoadingMessage()

// Builds the loading message that is by default shown in the right-top corner.
// The default loading message built here also depends on aranea.css.
// This method is always called during AJAX request. You are free to override it.
AraneaPage.buildLoadingMessage()

// Perform positioning of loading message (if needed in addition to CSS).
// Called before making the message element visible. This implementation
// provides workaround for IE 6, which doesn't support
// <code>position: fixed</code> CSS attribute; the element is manually
// positioned at the top of the document. If you don't need this, overwrite
// this with an empty function:
// 
Object.extend(AraneaPage, { positionLoadingMessage: Prototype.emptyFunction });

AraneaPage.positionLoadingMessage(element)


// ============================================================================
//                           FORM SUBMITTERS
// ============================================================================

// Here are three submitter classes for the standard HTTP submit, AJAX update
// region submit, and AJAX overlay submit.

// The standard HTTP submitter. Whether it's POST or GET depends on the
// "method" attribute of the "form" element. (The default is GET submit.)
var DefaultAraneaSubmitter = Class.create(

  // Local variables:

  systemForm: null,

  widgetId: null,

  eventId: null,

  eventParam: null,

  // Constructor:

  initialize(form)

  // Methods:

  // "Private" method that is called by event to store event data in local
  // variables.
  storeEventData(element)

  // Starts a submitting process. Here data is collected. Main work is done by
  // event_4().
  event(element)

  // Does a plain form submit using given parameters.
  event_4(systemForm, eventId, widgetId, eventParam)
});

// This class extends the default submitter, and overrides event() to initiate
// an AJAX request and to process result specifically for the overlay mode.
// It expects that aranea-modalbox.js is successfully loaded.
var DefaultAraneaOverlaySubmitter = Class.create(DefaultAraneaSubmitter, {

  event(element)

  event_7(systemForm, eventId, eventTarget, eventParam, eventPrecondition, eventUpdateRegions)

});

// This class extends the default submitter, and overrides event() to initiate
// an AJAX request and to process result specifically for update regions.
var DefaultAraneaAJAXSubmitter = Class.create(DefaultAraneaSubmitter, {

  // Local variable:
  updateRegions: null,

  event(element)

  event_5(systemForm, eventId, widgetId, eventParam, updateRegions)

  // Returns AJAX parameters for the request.
  getAjaxParameters(neededAraTransactionId, ajaxRequestId,
                  updateRegions, neededAraClientStateId)

  // Is called when the request completes successfully.
  onAjaxSuccess(ajaxRequestId, transport)

  // Is called when the request is completed.
  onAjaxComplete(transport)

  // Is called when the request fails.
  onAjaxFailure(transport)

  // Is called when an exception is called during request.
  onAjaxException(request, exception)

});

// The delay after which Ajax.Request onComplete expects all the DOM updates
// to have taken place, in milliseconds.
DefaultAraneaAJAXSubmitter.contentUpdateWaitDelay = 30

// An HTTP transport processor looking for state versioning info.
DefaultAraneaAJAXSubmitter.ResponseHeaderProcessor(transport)

// Region handler that updates transaction id of system form.
AraneaPage.TransactionIdRegionHandler = Class.create({
  process(content)
});

// The Region handler that updates DOM element content.
AraneaPage.DocumentRegionHandler = Class.create({
  process(content)
});

// Does DOM cleanup to avoid memory leaks when content is updated. An
// "invisible" second parameter is used to detect whether the clean-up is
// done with the element or not. If arguments.length = 1 then the input
// element is not changed, only its child-elements will be checked.
// Override this method (Object.extend()) to create your own cleanups.
AraneaPage.DocumentRegionHandler.doDOMCleanup(element)

// Handles messages that came with an AJAX request. These are the messages from
// the MessageContext. You do not need to put "messages" into your update
// regions if you have marked your messages with class "aranea-messages" and
// attribute "arn-msgs-type" with value of message type, because this handler
// knows how to update these messages.
// You may also override certain functionality to customize this class for your
// own needs.
AraneaPage.MessageRegionHandler = Class.create({

  regionClass: '.aranea-messages'

  regionTypeAttribute: 'arn-msgs-type'

  messageSeparator: '<br/>'

  process(content)

  // The input parameter is a map of messages by message type. This method goes
  // through all elements where class="aranea-messages", adds new messages to
  // them or hides messages if they were not in the response data.
  updateRegions(messagesByType)

  // This method adds messages (array) to given region (element).
  showMessageRegion(region, messages)

  // Hides given message region, and changes its content if necessary.
  hideMessageRegion(region)

  // Looks up the element that contains messages in given region.
  // Its content will be updated with new messages.
  findContentElement(region)

  // Looks up the element of the region that is intented for wrapping the messages.
  // It will be hidden, if no messages were in the response data.
  findDisplayElement(region)

  // Formats the messages (array) and returns them as String where messages are
  // separated by messageSeparator. The result is used to update the content of
  // content element (findContentElement(region)).
  buildRegionContent(messages)
});

// Region handler that opens popup windows.
AraneaPage.PopupRegionHandler = Class.create({

  process(content)

  openPopups(popups)

});

// Region handler that forces a reload of the page by submitting the system
// form.
AraneaPage.ReloadRegionHandler = Class.create({
  process(content)
});

// A region handler for form background validation.
AraneaPage.FormBackgroundValidationRegionHandler = Class.create({

  process(content)

  getParentSpan(formelement)

  getLabelSpan(formelement)

  getParentElement(el, tagName, className)

});


// Aranea page object is accessible in two ways: _ap and araneaPage().
var _ap = new AraneaPage();
function araneaPage() {
  return _ap;
}

Since Aranea 1.2.2, the JavaScript API also includes submit callback API, which can be used to provide more control over submitting. It contains methods that can be overridden to change or add some some behaviour.

/**
 * A common callback for API submitters. The callback handles common data manipulation and validation.
 * This callback should be used to add some custom features to submit data or submit response.
 */

// The only method that element-submitters should call. It takes the type of request, the form
// containing the element to be submitted, and the function that does the submit work.
AraneaPage.SubmitCallback.doRequest(type, form, element, eventFn);

// This method is called to return the result of element-submit. Here is a nice place to implement
// custom features depending on the element or request type. Feel free to override.
AraneaPage.SubmitCallback.getRequestResult(type, element, result);

// The method that is called by submitters to store submit data in the form.
AraneaPage.SubmitCallback.prepare(type, form, widgetId, eventId, eventParam)

// Processes the submit data. It calls following methods of this object:
// 1. processSubmitData - to optionally modify the submit data;
// 2. storeSubmitData - to store the submit data in the form (if submit is allowed).
// 3. Adds isSubmitAllowed, beforeSubmit, afterSubmit callbacks to data.
AraneaPage.SubmitCallback.processData(data)

// A callback to optionally modify submit data. Feel free to override.
AraneaPage.SubmitCallback.processSubmitData: function(data) {},

// A callback to store submit data in the form.
AraneaPage.SubmitCallback.storeSubmitData(data)

// A callback that is checked to enable or disable submit. Feel free to override.
isSubmitAllowed(data) {

// A callback that is called before each submit (no matter whether it is AJAX or not).
// This method includes default behaviour. Feel free to override.
AraneaPage.SubmitCallback.beforeSubmit(data)

// A callback that is called after each submit (no matter whether it is AJAX or not).
// This method includes default behaviour. Feel free to override.
AraneaPage.SubmitCallback.afterSubmit(data)
                        

The Aranea 1.2.2 release also introduced automatic file upload JavaScript API. You usually don't have to modify it except for the upload options part, especially the onComplete function. However, here's the entire API.

// This method returns the URL where to submit the file. The element parameter is not used, but
// you can modify the method to use the parameter. 
AraneaPage.getAjaxUploadURL(element);

// This method provides the data as { formField1: value1, formField2: value2, ...} that will be
// added to the form later. This data should be needed in the query.
AraneaPage.getAjaxUploadFormData(systemForm, element)

// This method is called by AraneaPage.init() to initialize file inputs with AJAX uplaod features.
// You can modify here the logic that is used for file input lookup.
AraneaPage.ajaxUploadInit()

// These are the default options that are used with the AJAX file upload. Feel free to override them.
AraneaPage.AjaxUploadOptions = {
        disabled: false,
        autoSubmit: true,
        onChange: function(file, extension, options) {},
        onSubmit: function(file, extension, options) {},
        onComplete: function(file, responseText, failMsg, options) {
                _ap.debug('File upload completed. File="' + file + '"; response="' + responseText + '".');
                if (responseText == 'OK') { // Otherwise responseText == 'FAIL'
                        // Hides the file input and shows a link instead with the file name. Once the link is
                        // clicked, the link will be removed and the file input will be shown again.
                        $(options.target).hide().insert({after:
                                '<a href="#" onclick="$(this).previous().show().next().remove(); return false;">' + file + '</a>'});
                } else {
                        if (!failMsg) {
                                failMsg = 'Uploading file "' + file + '" failed. There could have been a '
                                        + 'problem\nwith the connection or the file was too big. Please try again!';
                        }
                        alert(failMsg);
                }
        }
}