/* * Copyright 2005 Joe Walker * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *     http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *//** * Declare a constructor function to which we can add real functions. * @constructor */function DWREngine() { }/** * Set an alternative error handler from the default alert box. * @see http://getahead.ltd.uk/dwr/browser/engine/errors */DWREngine.setErrorHandler = function(handler) {  DWREngine._errorHandler = handler;};/** * Set an alternative warning handler from the default alert box. * @see http://getahead.ltd.uk/dwr/browser/engine/errors */DWREngine.setWarningHandler = function(handler) {  DWREngine._warningHandler = handler;};/** * Set a default timeout value for all calls. 0 (the default) turns timeouts off. * @see http://getahead.ltd.uk/dwr/browser/engine/errors */DWREngine.setTimeout = function(timeout) {  DWREngine._timeout = timeout;};/** * The Pre-Hook is called before any DWR remoting is done. * @see http://getahead.ltd.uk/dwr/browser/engine/hooks */DWREngine.setPreHook = function(handler) {  DWREngine._preHook = handler;};/** * The Post-Hook is called after any DWR remoting is done. * @see http://getahead.ltd.uk/dwr/browser/engine/hooks */DWREngine.setPostHook = function(handler) {  DWREngine._postHook = handler;};/** XHR remoting method constant. See DWREngine.setMethod() */DWREngine.XMLHttpRequest = 1;/** XHR remoting method constant. See DWREngine.setMethod() */DWREngine.IFrame = 2;/** * Set the preferred remoting method. * @param newmethod One of DWREngine.XMLHttpRequest or DWREngine.IFrame * @see http://getahead.ltd.uk/dwr/browser/engine/options */DWREngine.setMethod = function(newmethod) {  if (newmethod != DWREngine.XMLHttpRequest && newmethod != DWREngine.IFrame) {    DWREngine._handleError("Remoting method must be one of DWREngine.XMLHttpRequest or DWREngine.IFrame");    return;  }  DWREngine._method = newmethod;};/** * Which HTTP verb do we use to send results? Must be one of "GET" or "POST". * @see http://getahead.ltd.uk/dwr/browser/engine/options */DWREngine.setVerb = function(verb) {  if (verb != "GET" && verb != "POST") {    DWREngine._handleError("Remoting verb must be one of GET or POST");    return;  }  DWREngine._verb = verb;};/** * Ensure that remote calls happen in the order in which they were sent? (Default: false) * @see http://getahead.ltd.uk/dwr/browser/engine/ordering */DWREngine.setOrdered = function(ordered) {  DWREngine._ordered = ordered;};/** * Do we ask the XHR object to be asynchronous? (Default: true) * @see http://getahead.ltd.uk/dwr/browser/engine/options */DWREngine.setAsync = function(async) {  DWREngine._async = async;};/** * The default message handler. * @see http://getahead.ltd.uk/dwr/browser/engine/errors */DWREngine.defaultMessageHandler = function(message) {  if (typeof message == "object" && message.name == "Error" && message.description) {    alert("Error: " + message.description);  }  else {    alert(message);  }};/** * For reduced latency you can group several remote calls together using a batch. * @see http://getahead.ltd.uk/dwr/browser/engine/batch */DWREngine.beginBatch = function() {  if (DWREngine._batch) {    DWREngine._handleError("Batch already started.");    return;  }  // Setup a batch  DWREngine._batch = {};  DWREngine._batch.map = {};  DWREngine._batch.paramCount = 0;  DWREngine._batch.map.callCount = 0;  DWREngine._batch.ids = [];  DWREngine._batch.preHooks = [];  DWREngine._batch.postHooks = [];};/** * Finished grouping a set of remote calls together. Go and execute them all. * @see http://getahead.ltd.uk/dwr/browser/engine/batch */DWREngine.endBatch = function(options) {  var batch = DWREngine._batch;  if (batch == null) {    DWREngine._handleError("No batch in progress.");    return;  }  // Merge the global batch level properties into the batch meta data  if (options && options.preHook) batch.preHooks.unshift(options.preHook);  if (options && options.postHook) batch.postHooks.push(options.postHook);  if (DWREngine._preHook) batch.preHooks.unshift(DWREngine._preHook);  if (DWREngine._postHook) batch.postHooks.push(DWREngine._postHook);  if (batch.method == null) batch.method = DWREngine._method;  if (batch.verb == null) batch.verb = DWREngine._verb;  if (batch.async == null) batch.async = DWREngine._async;  if (batch.timeout == null) batch.timeout = DWREngine._timeout;  batch.completed = false;  // We are about to send so this batch should not be globally visible  DWREngine._batch = null;  // If we are in ordered mode, then we don't send unless the list of sent  // items is empty  if (!DWREngine._ordered) {    DWREngine._sendData(batch);    DWREngine._batches[DWREngine._batches.length] = batch;  }  else {    if (DWREngine._batches.length == 0) {      // We aren't waiting for anything, go now.      DWREngine._sendData(batch);      DWREngine._batches[DWREngine._batches.length] = batch;    }    else {      // Push the batch onto the waiting queue      DWREngine._batchQueue[DWREngine._batchQueue.length] = batch;    }  }};//==============================================================================// Only private stuff below here//==============================================================================/** A function to call if something fails. */DWREngine._errorHandler = DWREngine.defaultMessageHandler;/** A function to call to alert the user to some breakage. */DWREngine._warningHandler = DWREngine.defaultMessageHandler;/** A function to be called before requests are marshalled. Can be null. */DWREngine._preHook = null;/** A function to be called after replies are received. Can be null. */DWREngine._postHook = null;/** An array of the batches that we have sent and are awaiting a reply on. */DWREngine._batches = [];/** In ordered mode, the array of batches waiting to be sent */DWREngine._batchQueue = [];/** A map of known ids to their handler objects */DWREngine._handlersMap = {};/** What is the default remoting method */DWREngine._method = DWREngine.XMLHttpRequest;/** What is the default remoting verb (ie GET or POST) */DWREngine._verb = "POST";/** Do we attempt to ensure that calls happen in the order in which they were sent? */DWREngine._ordered = false;/** Do we make the calls async? */DWREngine._async = true;/** The current batch (if we are in batch mode) */DWREngine._batch = null;/** The global timeout */DWREngine._timeout = 0;/** ActiveX objects to use when we want to convert an xml string into a DOM object. */DWREngine._DOMDocument = ["Msxml2.DOMDocument.5.0", "Msxml2.DOMDocument.4.0", "Msxml2.DOMDocument.3.0", "MSXML2.DOMDocument", "MSXML.DOMDocument", "Microsoft.XMLDOM"];/** The ActiveX objects to use when we want to do an XMLHttpRequest call. */DWREngine._XMLHTTP = ["Msxml2.XMLHTTP.5.0", "Msxml2.XMLHTTP.4.0", "MSXML2.XMLHTTP.3.0", "MSXML2.XMLHTTP", "Microsoft.XMLHTTP"];/** * @private Send a request. Called by the Javascript interface stub * @param path part of URL after the host and before the exec bit without leading or trailing /s * @param scriptName The class to execute * @param methodName The method on said class to execute * @param func The callback function to which any returned data should be passed *       if this is null, any returned data will be ignored * @param vararg_params The parameters to pass to the above class */DWREngine._execute = function(path, scriptName, methodName, vararg_params) {  var singleShot = false;  if (DWREngine._batch == null) {    DWREngine.beginBatch();    singleShot = true;  }  // To make them easy to manipulate we copy the arguments into an args array  var args = [];  for (var i = 0; i < arguments.length - 3; i++) {    args[i] = arguments[i + 3];  }  // All the paths MUST be to the same servlet  if (DWREngine._batch.path == null) {    DWREngine._batch.path = path;  }  else {    if (DWREngine._batch.path != path) {      DWREngine._handleError("Can't batch requests to multiple DWR Servlets.");      return;    }  }  // From the other params, work out which is the function (or object with  // call meta-data) and which is the call parameters  var params;  var callData;  var firstArg = args[0];  var lastArg = args[args.length - 1];  if (typeof firstArg == "function") {    callData = { callback:args.shift() };    params = args;  }  else if (typeof lastArg == "function") {    callData = { callback:args.pop() };    params = args;  }  else if (typeof lastArg == "object" && lastArg.callback != null && typeof lastArg.callback == "function") {    callData = args.pop();    params = args;  }  else if (firstArg == null) {    // This could be a null callback function, but if the last arg is also    // null then we can't tell which is the function unless there are only    // 2 args, in which case we don't care!    if (lastArg == null && args.length > 2) {      if (DWREngine._warningHandler) {        DWREngine._warningHandler("Ambiguous nulls at start and end of parameter list. Which is the callback function?");      }    }    callData = { callback:args.shift() };    params = args;  }  else if (lastArg == null) {    callData = { callback:args.pop() };    params = args;  }  else {    if (DWREngine._warningHandler) {      DWREngine._warningHandler("Missing callback function or metadata object.");    }    return;  }  // Get a unique ID for this call  var random = Math.floor(Math.random() * 10001);  var id = (random + "_" + new Date().getTime()).toString();  var prefix = "c" + DWREngine._batch.map.callCount + "-";  DWREngine._batch.ids.push(id);  // batchMetaData stuff the we allow in callMetaData for convenience  if (callData.method != null) {    DWREngine._batch.method = callData.method;    delete callData.method;  }  if (callData.verb != null) {    DWREngine._batch.verb = callData.verb;    delete callData.verb;  }  if (callData.async != null) {    DWREngine._batch.async = callData.async;    delete callData.async;  }  if (callData.timeout != null) {    DWREngine._batch.timeout = callData.timeout;    delete callData.timeout;  }  // callMetaData stuff that we handle with the rest of the batchMetaData  if (callData.preHook != null) {    DWREngine._batch.preHooks.unshift(callData.preHook);    delete callData.preHook;  }  if (callData.postHook != null) {    DWREngine._batch.postHooks.push(callData.postHook);    delete callData.postHook;  }  // Default the error and warning handlers  if (callData.errorHandler == null) callData.errorHandler = DWREngine._errorHandler;  if (callData.warningHandler == null) callData.warningHandler = DWREngine._warningHandler;  // Save the callMetaData  DWREngine._handlersMap[id] = callData;  DWREngine._batch.map[prefix + "scriptName"] = scriptName;  DWREngine._batch.map[prefix + "methodName"] = methodName;  DWREngine._batch.map[prefix + "id"] = id;  // Serialize the parameters into batch.map  DWREngine._addSerializeFunctions();  for (i = 0; i < params.length; i++) {    DWREngine._serializeAll(DWREngine._batch, [], params[i], prefix + "param" + i);  }  DWREngine._removeSerializeFunctions();