Ajax Hacks

Event Listener Adapter Rich Internet Components

Tue, 27 Sep 2011 09:55:58 GMT

As described in Chapter 2, the UIInput component delivers a ValueChangeEvent to all registered event listeners. In addition, the ValueChangeEvent is also delivered to the backing bean via a MethodBinding stored in the UIInput's valueChangeListener attribute. The valueChangeListener attribute is exposed as a tag attribute on the standard input tags, such as lt h inputText gt .In JSF 1.2, the valueChangeListener attribute is deprecated on the UIInput component but is still present on the JSP tag...

The StateBag Class and the IStateManager Interface AJAXComponents

Tue, 27 Sep 2011 09:24:09 GMT

The client-side state management technique ViewState exists in the .NET Framework class hierarchy as a member property of the System.Web.UI.Control class called ViewState, of type StateBag, which implements a dictionary data structure to store name value pairs. The StateBag class implements the interfaces in Table 3-3. Table 3-3. Interfaces Implemented by the StateBag Class Table 3-3. Interfaces Implemented by the StateBag Class Defines enumerators, synchronization methods, and size for...

How will caching be controlled RelatedPatterns

Tue, 27 Sep 2011 09:07:56 GMT

It's possible that an XMLHttpRequest response will be cached by the browser. Sometimes, that's what you want and sometimes it's not, so you need to exert some control over caching. With cache control, we're talking about GET-based requests. Use GET for read-only queries and other request types for operations that affect server state. If you use POST to get information, that information usually won't be cached. Likewise, if you use GET to change state, you run the risk that the call won't always...

SOA WOA and SaaS ApplicationLayer

Tue, 27 Sep 2011 09:07:29 GMT

SOA components contain Web services, RPC layer services for applications, and generic services written in traditional applications. Most of the SOA components are written in Web services, as modeled in Figure 2.11. A Web Service can be defined in the following way A Web service is a software component developed to support interoperability over a network using an interface described in WSDL, a machine-understandable format. Other systems communicate with the Web service, using SOAP messages that...

The Yahoo Geocoding API GoogleMaps

Tue, 27 Sep 2011 09:05:00 GMT

Currently, the Yahoo Geocoding API is really useful only for geocoding addresses in the United States, though with competition from Google, we're sure this will change. Before Google's geocoder came along, this was the geocoder of choice for many people doing US-centric mashups using both the Google Maps API and the Yahoo Maps API. The only real limitation is that you can make only 5,000 lookup requests per day per IP address . Caution The rate limit for Yahoo is based on a 24-hour window, not...

The scroll event EventObjects

Tue, 27 Sep 2011 09:00:27 GMT

You may also want to keep track of when a user scrolls the window or another element in order to ensure something remains visible on the screen at all times. By using the scroll event, this is easy lt title gt OnScroll Example lt title gt lt head gt lt body lt p gt Try scrolling this window. lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p gt lt p gt amp nbsp lt p...

Writing a simple test case DashboardApplications

Tue, 27 Sep 2011 08:44:20 GMT

In JUnit, a test case is a class that may contain one or more tests. The purpose of the test case is to group a set of tests together, typically based on their function. For example, you may want to place all tests for a calendar widget in the same class, potentially allowing you to write private methods that can be shared among the tests. In the example, you'll write a test case that tests basic math functionality, giving you a feel for how to use JUnit. You begin by creating a new class named...

CSRF Vulnerability Detection with Web Applications ApplicationLayer

Tue, 27 Sep 2011 08:30:39 GMT

Traditional CSRF vulnerabilities can be identified by analyzing each important get and post request going to the application. If an attacker can reproduce a get or post request, this can lead to CSRF. If a specific get or post request on an application throws some magic number that cannot be guessed easily, this can act as a token to guard against a CSRF attack vector. This magic token can be part of a querystring in a GET request while in a data buffer as part of a posT request. These tokens...

Info Uhl ServerControls

Tue, 27 Sep 2011 08:27:29 GMT

Returns all behaviors attached to a DOM element that are of a particular type. return Sys.UI.Behavior. getBehaviorsByType element, typeName Returns a behavior attached to a DOM element if it was found. return Sys.UI.Behavior. getBehaviorByName Returns a copy of the return Sys.UI.Behavior. behaviors attached to a getBehaviors

Emulating Classes Ajax Library 2

Tue, 27 Sep 2011 07:44:19 GMT

As stated earlier, JavaScript doesn't use classes, but instead is prototype-based. Nevertheless, what JavaScript can do is emulate classes. Class emulation begins with constructors. You are familiar with constructors in .NET they are similar in JavaScript, but the big difference is that within the constructor you are able to declare properties for the object. The Point class function Point x, y this._x x this._y y this.toString function return this._x , this._y You can then use the new operator...

Setting new document preferences Dreamweaver CS3 Ajax

Tue, 27 Sep 2011 07:43:33 GMT

Click the Preferences button at the bottom left of the New Document dialog box. Alternatively, choose Preferences from the Edit menu Dreamweaver menu on a Mac , and select the New Document category. Either presents you with the New Document Preferences dialog box shown in Figure 1-3. The dialog box lets you set the following global preferences Default document lets you choose the type of document that will be created when you use the keyboard shortcut for a new document Ctrl N Cmd N . For this...

The CascadingDropDown Extender Ajax Extensions 2

Tue, 27 Sep 2011 07:10:49 GMT

The CascadingDropDown extender can be attached to a DropDownList control to automatically populate it based on the current selection of one or more parent DropDownList controls. The CascadingDropDown extender is designed to fit in a relatively common scenario in which the contents of one drop-down list depends on the selection of another list. In this way, you don't need to transfer to the client the entire data set from which a child list can select a subset of items to display in accordance...

Discussion Wap AjaxStruts

Tue, 27 Sep 2011 07:08:24 GMT

You often need to verify that users have checked at least one choice from a set of checkboxes or selected one or more options from a select list. Both of these validations can be performed using the Validator's predefined required rule. However, validating users who have chosen more than one item requires a custom rule like the one shown in the Solution. You create the minchoices rule using the same basic steps outlined inRecipe 8.7. The rule requires that the validated field must be an array...

Wrapping it up in finally Ajax Struts 2

Tue, 27 Sep 2011 06:54:24 GMT

What happens if you absolutely, positively have to do something regardless of whether or not an exception is thrown You can use a third block for that purpose called the finally block, which can be used only in the try catch block. The finally block is guaranteed to always execute regardless of whether or not an exception was thrown. To see how you might use the finally block, suppose that you're performing some database operation in the try block that throws a SQLException. Before making the...

Dropping and Adding Items RemoteScripting

Tue, 27 Sep 2011 06:52:15 GMT

The checkltemAcceptance method relies on some housekeeping operations performed as items are dropped it expects the box weight to be correct and the allRMASerials list to be up-to-date. These go into Tree's onDndDrop extension point. The chain of events on a drop goes like this 1. The user lets go of the mouse. 2. checkAcceptance and checkltemAcceptance are called. If they both return true, the drop proceeds. 3. Tree updates the display and the data store. 4. Lastly, Tree calls the onDndDrop...

The use Attribute DataBinding

Tue, 27 Sep 2011 06:51:36 GMT

Embedding code improperly in pages might cause a maintenance headache, so it's best to separate control code from the code for the UI. There are two ways to separate code from views. First, you could put these control codes in a separate Java class, and then register event listeners to invoke the proper methods accordingly. For example, you could invoke your methods to initialize or to cancel a process by registering the onCreate , onOK , and onCancelQ event listeners to invoke those methods...

AccordionContainer Dojo

Tue, 27 Sep 2011 06:19:27 GMT

Like a TabContainer, AccordionContainer inherits from StackContainer and is a means of displaying one child at a time from a collection of widgets. The visual difference is that the container looks like a vertical accordion, and animates when each child is selected. One important difference in how you use AccordionContainer, however, is that you must use a special child container called AccordionPane that provides an explicit wrapper for its child widgets. The actual reasoning for why this is...

GetState SetState ShoppingCarts

Tue, 27 Sep 2011 04:33:43 GMT

lTttp yjGcalfr gt 5t BQ68 - Prsrceissliig Remote - Mo _ X Figure 3-3. Applying the Representation Morphing pattern when adding two numbers Figure 3-3 shows two referenced representations Number and Result. Each of the representations has associated two methods GetState and SetState. The purpose of the methods is to extract and assign state to a representation. In programmatic terms, the representations and the associated methods represent a contract. Notice that it has not been mentioned how...

defaultChecked JavaScriptReference

Tue, 27 Sep 2011 03:52:08 GMT

Compatibility WinIE3 , MacIE3 , NN2 , Moz , Safari Sometimes you may find it beneficial to know if the initial setting of a checkbox has changed. The checked property alone can't tell you this because it reflects only the current state of a checkbox. Another property, defaultChecked, keeps up with the initial state of a checkbox. If you add the checked attribute to the lt input gt definition for a checkbox, the defaultChecked property for that object is true otherwise, the property is false....

Solution Kiy AjaxStruts

Tue, 27 Sep 2011 01:48:43 GMT

Use Niall Pemberton's Lazy DynaBean forms available for download from Declare the form-bean to use in the struts-config.xml lt form-bean name LazyForm Then, use the form on a JSP page as you would a normal ActionForm. Example 5-8 shows a JSP page lazy_form_test.jsp that will utilize the LazyForm declared previously. Example 5-8. Using the LazyValidatorForm on an HTML form lt page language-'java gt lt taglib prefix html gt lt taglib prefix bean gt lt html gt lt head gt lt title gt Struts...

Synchronizing ViewState Aspnet Ajax 2

Tue, 27 Sep 2011 01:45:27 GMT

One of the things that is integral to ASP.NET is the ViewState. The ViewState is encoded data that saves important data about a page in a special hidden form element called __ViewState. This data includes values that are bound to a grid, drop-down list, or other form element. This information is used to keep the data consistent between page postbacks as well as allow for change events to occur on this page. The problem with this is that with ASP.NET AJAX calls can be made to the server and...

To monitor a URL AdobeAIR

Tue, 27 Sep 2011 00:47:46 GMT

1. In your project's primary HTML file, include the Shockwave file Script 13.1 lt script src servicemonitor.swf type application x-shockwave- flash gt lt script gt To use the URLMonitor class, an application must include this file. For the type attribute, make sure you specify its value as application x-shockwave-flash. 2. In a JavaScript block, create the two objects var url new air.URLRequest 'http www.example.com' var monitor new air.URLMonitor url This code is pretty much the same as the...

The NewsTickerFeed Class EventHandlers

Mon, 26 Sep 2011 23:58:07 GMT

A news ticker isn't very useful without content to display. The NewsTickerFeed class pulls the required feeds, parses them with XParser, and assembles the HTML for the ticker. The constructor accepts two arguments a reference to its the NewsTicker object this allows access to the NewsTicker properties and methods when needed and the URL of the feed to download function NewsTickerFeed oParent, sUrl this.parent oParent this.url sUrl this.timer null this.container null Compared to the NewsTicker...

Internationalization in Dojo

Mon, 26 Sep 2011 23:40:11 GMT

This chapter provides a brief synopsis of the tools Dojo provides for internationalizing a module. The key topics are defining bundles on a locale basis and using Core's facilities for formatting and parsing dates, currency, and numbers. In case it wasn't quite obvious, internationalization is usually abbreviated as i18n simply because it is such a long word to type thus, the shorthand is the first and last letters, with the number 18 between them to take place of the 18 letters in between.

Defining Dynamic HTTP Validation AjaxPatterns

Mon, 26 Sep 2011 23:27:55 GMT

For those websites that read data as often as it is written, the static HTTP validation approach would be wrong because updating the file takes too many resources. In the case of dynamic HTTP validation, the server application framework has to manage everything, which includes the generation and verification of the entity tag. The major problem to solve is the generation of the entity tag ETag identifier. Traditionally, web developers do not write an ETag identifier. But what is an entity tag...

Caching on the Server HighPerformance

Mon, 26 Sep 2011 23:00:13 GMT

Although the previous section covered most of the caching mechanisms for both the browser and the web server, there are other ways by which we can cache data on the server. The server is often not the last link in the chain, and it often works with data that it must retrieve from files on the system, or data in a database. Therefore, if we can find efficient ways to cache this data, we can again avoid the expensive operations required to retrieve the data from its original source. With...

Implementing a continuously updating component DashboardApplications

Mon, 26 Sep 2011 22:47:42 GMT

In this section, we'll revisit the Server Status component and allow it to periodically update itself. To do this, you'll add the ability to set the refresh rate for the data, as well as add the ability to change or stop the automatic updates. In doing so, we'll need to look at the GWT Timer class, which allows you to trigger timed events. If you've been following along with us, your Server Status component should be working and have a method that can be called to have it update its information...

ItemFileReadStore and Trees RemoteScripting

Mon, 26 Sep 2011 21:39:46 GMT

An ItemFileReadStore can nest JSON hashes within JSON hashes, a technique we saw in Section 3.2, Literals and Hashes, on page 39.2 That structure translates directly to a tree a nested hash will display as a folder node that you can expand. 2. This kind of nesting is called native nesting. ItemFileReadStore also supports reference nesting, allowing more complex relationships such as assigning multiple parents to a child. These relationships cannot be modeled with a Tree anyway, but if you're...

Using variables in a SQL query Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 21:03:52 GMT

Changed To out whether an author has already been registered, you need to check the authors table to see if any record matches the values submitted in the first_name and family_name fields. In other words, you need to search the database or in this case, a single table . If there's a match, you need to stop the Insert Record server from executing. Otherwise, the insert operation can go ahead. Since you don't know what will be entered in the form fields, you need to pass their values as...

Discussion Gma AjaxStruts

Mon, 26 Sep 2011 20:51:22 GMT

Though the Validator offloads much of your hand-written code to a configuration file, more complex validations may be required. Two general types of validation exist syntactic and semantic. Syntactic validation verifies the syntax of the data, and semantic validation verifies that the data is meaningful from a business sense. The Validator does syntactic checks well but isn't purposed for semantic validation. Usually, this validation needs to be hand-written. Fortunately, the Validator doesn't...

Multiplexing Requests AjaxReference

Mon, 26 Sep 2011 20:46:10 GMT

Instead of fighting with the connection limit, it may be better to consider sending the requests in batches. Yes, you read that right we are promoting a batch concept here. Take three or four requests, put them into one Ajax request, and send it on its way to the server. This is just the simple idea of multiplexing applied to Ajax. Now, you should doubt this approach as it would seem to be a return to the old style. However, what is being suggested is not waiting around for a batch request, but...

Capturing the Postback via IPostBackEventHandler AJAXComponents

Mon, 26 Sep 2011 20:24:31 GMT

As part of our design, we had the requirement of rendering the button as either a normal button or as a specially configured hyperlink to submit the web form. With events in hand, we now move on to hooking the button click into the postback process through implementation of the IPostBackEventHandler interface. To achieve this, we next implement the single method of the postback interface, RaisePostBackEvent public void RaisePostBackEvent string argument RaisePostBackEvent takes a single...

Tampering with Data Types of the SOAP Message ApplicationLayer

Mon, 26 Sep 2011 20:15:13 GMT

Here is an example of a SOAP request that takes an array as input. lt xml version 1.0 encoding utf-16 gt lt soap Envelope lt soap Body lt tns solvesys gt lt Arr href id1 gt lt tns solvesys gt lt soapenc Array id id1 lt Item gt 0 lt Item gt lt soapenc Array gt lt soap Body gt lt soap Envelope gt The following node gives away information about the input parameter an array of items. lt soapenc Array id id1 lt Item gt 0 lt Item gt lt soapenc Array gt xsd double indicates that the array consists of...

ReorderList Control Server Controls 3

Mon, 26 Sep 2011 20:14:41 GMT

In many web and desktop applications, you may have come across the typical UI construct for reordering lists that is often done by two buttons one for Up and another for Down placed adjacent to the list itself. The user then has to select the item in the list and click the appropriate button enough times to get the selected item in the designated position. It would certainly be nice to be able to simply drag the item to the desired position instead. You have already seen how easy it is with the...

Accessing Complex Properties with JSTL AjaxStruts

Mon, 26 Sep 2011 20:04:13 GMT

More interesting in Example 3-17 is how the JSTL expression language EL is used to retrieve the collection of IDEs for the chosen language language The power of EL allows you to access normal JavaBean properties as well as mapped properties in almost any combination. To understand how the expression is evaluated, let's examine how it would be done in Java Map ideMap languageChoices.getLanguageldeMap get the selected language from the form bean DynaActionFrom form DynaActionForm String language...

Controlling Browser History AjaxLinq

Mon, 26 Sep 2011 19:43:19 GMT

It has been said that he who controls history, controls the future. That is certainly true when using a browser. Everyone is familiar with the browser Forward and Back buttons, which allow the user to navigate back and forth amongst the pages already visited in the current session. Forward and Back are central to the browsing experience. The browser automatically enables and disables these buttons as necessary, if there are appropriate pages to navigate to. For example, if you are at the first...

Implementing the Standard Flash Widget Google Web Toolkit

Mon, 26 Sep 2011 19:32:32 GMT

The standard implementation for the Flash widget creates the EMBED tag, as shown in Listing 15.129 by simply stringing together a number of Strings. In a real implementation, we would use the parameters passed in to set dimensions, etc., but, in our example, we just hard code all the parameters. Note that, in the URL, we set the title value to be the word Other, which is what we expect to be displayed on screen. Listing 15.129 Defining the Flash widget's implementation class for the majority of...

Moving JavaScript to an external file Dreamweaver CS4 Ajax

Mon, 26 Sep 2011 19:16:52 GMT

This exercise demonstrates how to use the JavaScript Extractor using spry_selector.html from the preceding section. 1. Because the JavaScript Extractor cannot restore JavaScript once it has been removed from a page, it's always a good idea to create a new copy of the file that you want to work on. Save spry_selector.html from the previous exercise or from examples ch08 as spry_unobtrusive.html in workfiles ch08. 2. Close the original file and work with spry_unobtrusive.html. 3. Select Commands...

Encapsulating Remote Calls in a Faade Google Web Toolkit

Mon, 26 Sep 2011 19:15:18 GMT

The Fa ade pattern is one of the software patterns described in the famed book Design Patterns Elements of Reusable Object-Oriented Software by Gamma, Helm, Johnson, and Vlissides. This book defines the fa ade software pattern as a way of providing a higher-level interface to make a subsystem easier to use. In our case we want to encapsulate all of the RPC logic into a class that provides a simple interface in an effort to achieve the following Reduce complexity by reducing the number of...

Giving elements a unique identity Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 19:06:43 GMT

An id attribute is like an ID in real life to provide a positive method of identification, an id attribute must be unique in the same way as a Social Security number. Once you have assigned an id, you must not reuse it within the same page. You can reuse it elsewhere in the same site, but only once in each page. Many web designers blithely ignore this rule, because CSS usually works perfectly well even if the same id is used several times on a page. Moreover, in spite of its commitment to...

Checked and Unchecked Exceptions StrutsFramework

Mon, 26 Sep 2011 18:35:37 GMT

Java exceptions can be separated into two distinct groups checked and unchecked. A checked exception signals an abnormal condition that the client must handle. All checked exceptions must either be caught and handled within the calling method or be declared in the throws clause following the method signature. This is why they are called checked. The compiler and the JVM will verify that all checked exceptions that can occur in a method are handled. The compiler and JVM don't care if unchecked...

ConfirmButtonExtender Control Server Controls 3

Mon, 26 Sep 2011 17:47:31 GMT

The ConfirmButtonExtender control, as the name suggests, captures the Click event of a button and displays a confirmation dialog box. If the user clicks OK after that, the button will function as implemented otherwise, the Click event will simply be ignored. This control is so simple that it only has two properties TargetControlID and ConfirmText. As you probably have guessed already, TargetControlID contains the ID of the target button, and ConfirmText holds the text message that will be...

referrer JavaScriptReference

Mon, 26 Sep 2011 17:46:47 GMT

Compatibility WinIE3 , MacIE3 , NN2 , Moz , Safari When a link from one document leads to another, the second document can, under JavaScript control, reveal the URL of the document containing the link. The document.referrer property contains a string of that URL. This feature can be a useful tool for customizing the content of pages based on the previous location the user was visiting within your site. A referrer contains a value only when the user reaches the current page through a link. Any...

ScriptControlDescriptor Server Controls 2

Mon, 26 Sep 2011 16:57:34 GMT

Listing 17-8 presents the implementation of the replica ScriptControlDescriptor. As you can see, this class derives from the ScriptComponentDescriptor base class discussed in the previous sections. Note that the constructor of the ScriptControlDescriptor class makes use of the internal constructor of the ScriptComponentDescriptor base class. As discussed earlier, this internal constructor takes two parameters, the first containing the fully qualified name of the type of the ASP.NET AJAX control...

I Chapter Hqu AjaxApplications

Mon, 26 Sep 2011 16:48:19 GMT

When we built the server-side code, we returned text strings that contained JavaScript statements in the responseText of our returned object. In order to effectively use the JavaScript statements, we must process them with the eval method, which determines exactly what the strings contain and executes it. In this case, the string is either going to contain the error message generated by the LoginFilter failing, or the code to build the windows, if the filter lets us through to the SelectServlet...

Discussion Ige AjaxStruts

Mon, 26 Sep 2011 16:27:29 GMT

The typical Action returns an ActionForward from itsexecute method. The returned ActionForward is evaluated and processed by the Struts request processor. The returned forward specifies the path to a resource, like a JSP page, that generates the actual HTTP response. However, you can generate the response in the Action. If you do so, you must returnnull from the Action's execute method. This tells the Struts request processor no ActionForward will follow therefore, the response should be...

Multilingual Support StrutsFramework

Mon, 26 Sep 2011 16:18:39 GMT

Most of us cringe at the thought of supporting user groups that are in one of several possible locales. In many cases, however, once an application has been installed and localized, it's like any other single-locale application. The users that access the application are either all from the same locale or are from locales similar enough that the language and cultural differences are insignificant. Multilingual applications, on the other hand, take internationalization to the next level by...

Sending Results to the Client ScriptTypes

Mon, 26 Sep 2011 15:53:45 GMT

As I just showed in Example 16-5, the server will take care of creating the XHTML to send to the client so that the hints will appear to the user as quickly as possible. This is accomplished by taking the responseText of the server's response and immediately setting it to the innerHTML of the lt div gt element before making the lt div gt element visible. Each hint result that is passed to the client must be capable of submitting the search form to the server. An onclick event should be set for...

Using the UpdatePanel UpdateProgress and Timer Controls Server Controls 3

Mon, 26 Sep 2011 15:46:16 GMT

For this first example, consider the following scenario You have a data-driven web page that needs to continuously alert the user with fast changing data, for instance, a page that displays the major financial indices in the U.S. capital markets Dow Jones Industrial Average DJIA , NASDAQ, and S amp P500. One approach is to place a lt META gt tag in your page with refresh values that then force the page to refresh itself in regular intervals based on the provided value. But if you wanted to make...

Listing The onComplete Private JavaScript Function Server Controls 2

Mon, 26 Sep 2011 15:43:38 GMT

function onComplete response, eventArgs if response.get_responseAvailable var contentType if result response.get_object else if result response.get_xml result response.get_responseData var error var errorObj error true if errorObj result new Sys.Net.WebServiceError false, result.Message, result.StackTrace, result.ExceptionType var statusCode response.get_statusCode if statusCode lt 200 statusCode gt 300 errorObj result new Sys.Net.WebServiceError false timedout , methodName , ,...

Step Defining the realms Ajax Struts 2

Mon, 26 Sep 2011 15:40:03 GMT

The second step is to define a realm in the Web container's server.xml file. A realm identifies a set of users, their passwords, and their associated roles. Four types of realms are possible, depending on how you set up your user information I UserDatabaseRealm The simplest but least flexible and secure choice. In this scenario, usernames, passwords, and roles are kept in a static file that is loaded into the Web container's memory at startup. For Tomcat, this file defaults to tomcat-users.xml....

Signing Content AccessControl

Mon, 26 Sep 2011 15:34:20 GMT

A way of gaining trust with users is to prove that you are legit. Own your own words. Digitally sign your stuff, so that people know it came from you. This applies to everything on the Web web pages, RSS and ATOM feeds, blogs go nuts If you sign the content, people have an assurance that what they are getting is from a more trusted source. Also, if you share your public key for verifying your signature on a web page protected with SSL, you can extend the trust of the certificate providing SSL...

Table of Contents Ajax Struts 2

Mon, 26 Sep 2011 15:33:29 GMT

About This How to Use This Book Foolish Assumptions Conventions Used in This Book How This Book Is Part I Getting to Know Jakarta Struts Part II Starting from the Part III Expanding Your Development Options 4 Part IV Putting It All Part V The Part of Part VI Icons Used in This Where to Go from Part I Getting to Know Jakarta Struts 7 Chapter 1 Starting with the Basics 9 What Is Jakarta Struts Structuring a Web Application Using Java Creating JavaServer Pages Using JavaBeans Understanding the...

Development Environment with Eclipse JavascriptFunctions

Mon, 26 Sep 2011 15:02:05 GMT

The Eclipse IDE that we use is the recent Eclipse Ganymede release. Eclipse IDE comes in many packages and the one that we use here is Eclipse IDE for Java EE Developers. This package includes tools for developing JEE and web applications, and it has all the prerequisites of the Geronimo Eclipse Plugin that we install here. The easiest way to install the Geronimo Eclipse Plugin is to let Eclipse WTP Web Tools Platform to do the download and installation. After starting Eclipse, we specify a new...

Throwing Exceptions Google Web Toolkit

Mon, 26 Sep 2011 15:01:06 GMT

Often it is desirable to allow a method to throw an exception that will be handled by the calling code. For example you may have a login function that returns a user data object on success, but, on failure, it throws an appropriate exception. 1.2351 UserData loginUser String username, String password 1.2352 throws FailedAuthenticationException When GWT calls your service method, and it throws an exception, it will serialize the exception and return it to the client browser. The only requirement...

IScriptControl Server Controls 2

Mon, 26 Sep 2011 14:58:07 GMT

All ASP.NET AJAX script server controls implement an interface named IScriptControl, defined in Listing 17-3. As you can see, the IScriptControl interface exposes two methods GetScriptDescriptors The GetScriptDescriptors method of the IScriptControl interface plays the same role in a script server control that the GetScriptDescriptors method of the IExtenderControl plays in an extender server control. Recall that the GetScriptDescriptors method of the IExtenderControl interface takes a...

Validating a checkbox group with Spry Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 14:56:02 GMT

Validating a checkbox group is easy, but the default use of lt span gt tags makes it difficult to create a layout that uses valid code and looks halfway decent. However, this is also a good opportunity to show you that you don't need to be constrained by Dreamweaver's way of doing things. The best way to explain is with a practical example based on the form you have been using throughout the chapter. The form has a group of five checkboxes displayed in two columns, each of which is formed by a...

Displaying a random quotation Dreamweaver CS4 Ajax

Mon, 26 Sep 2011 14:55:23 GMT

The Stroll Along the Thames page you've used in several chapters has a pull quote with a quotation from Samuel Johnson. In this exercise, you'll replace that static quotation with one drawn at random from the authors and quotations tables. This demonstrates three useful techniques how to join multiple tables, randomize the order of recordset results, and limit the number of results. You can use an existing version of the page, as long as it has a .php extension. However, you will probably find...

Posting form elements without a page submit AjaxRequests

Mon, 26 Sep 2011 14:22:10 GMT

The vast majority of web pages that accept input today are written using the classical technique of submitting a form to the server when data entry is complete. This entails a complete page refresh, which may be undesirable in the context of the rich web applications that we can now deliver using Ajax. We want to post a form to a server resource without a full-page reload. Solution As it turns out, the solution is almost completely trivial. In fact, we've already pretty much accomplished this...

CodeBehind and Service Layer AspnetAjax

Mon, 26 Sep 2011 14:13:49 GMT

In a model where server controls are used to produce the user interface and JavaScript is mostly used to refresh the DOM and trigger asynchronous requests, do you really need an HTTP fa ade If you adopt the AJAX Server Pages pattern, you can have an HTTP fa ade, but you aren't forced to have one in your applications. The AJAX Server Pages pattern requires you to write all or at least most of your Web application in managed code, thus abstracting away JavaScript and AJAX machinery. Don't...

Using the endRequest Event Server Controls 2

Mon, 26 Sep 2011 14:05:19 GMT

As the name suggests, the current PageRequestManager instance raises the endRequest event to mark the end of the current asynchronous page postback request. Since the _endPostBack method can be invoked for a number of reasons, the endRequest event can be raised for a number of reasons as well. In other words, your event handler for the endRequest event must not assume that everything went fine and the server response successfully arrived. It must include the necessary logic to determine why the...

Understanding the XMLHttpRequest API AjaxController

Mon, 26 Sep 2011 14:01:55 GMT

9 of 37 22 08 2006 09 02 15 When building real-world applications, you should look for an Ajax framework that wraps the XMLHttpRequest API, implementing additional features, such as error handling, form-XML bindings, and so on. Frameworks also hide browser differences, which are a common issue when using JavaScript. In our case here, however, no Ajax framework is used because one of the goals is to help you understand how XMLHttpRequest works.The code presented in this section can be found in...

GPoint and GLatLng Google Maps 2

Mon, 26 Sep 2011 13:41:50 GMT

Prior to Version 2 of the Google Maps API, the GPoint class was used to represent a single, 2-dimensional longitude latitude point of interest somewhere on the face of the earth. However, with Version 2, geographic coordinates are now being represented by a new class GLatLng. GPoint now represents a point on a map by its pixel coordinates. This is a significant change that will need to be incorporated by existing Google Maps Version 1 sites and will necessitate changes to those applications....

CascadingDropDown Control Server Controls 3

Mon, 26 Sep 2011 13:03:36 GMT

The CascadingDropDown control is ideal for situations when you need to have multiple drop-downs on a web page with the value s of each drop-down control being dependent on the selection from the previous one. In fact, you've probably seen many sites taking advantage of this pattern. For instance, when you visit your printer or other computer accessories' manufacturer site in search of the appropriate driver s , you are often presented with a list of drop-down controls in order to find the right...

DOM Shortcuts JavascriptCode

Mon, 26 Sep 2011 12:53:17 GMT

Fortunately, the DOM API includes a few shortcuts. Document objects have a method, getElementsByTagName , that could have come in handy in our example. Consider this alternate JavaScript function var divElements var divElement divElements 0 world , divElement.childNode s 0 That's much more palatable. Sure, but we still have the brittle ordering problem. We're assuming that the lt div gt element that we're interested in will always occur in the same location relative to other lt div gt elements....

Remote Procedure Calls Defined Remote Scripting 2

Mon, 26 Sep 2011 12:23:40 GMT

Loosely speaking, a remote procedure call RPC is a mechanism for one process to execute a function in another process and receive the result as if the function call were local. Although it's true that any interprocess communication IPC ultimately executes a function in another process, the bit about as if the function were local is what differentiates RPC from generic IPC. All RPC systems have similar design. A package is constructed by the calling process that contains the identification of...

Step Creating a request object RequestObjects

Mon, 26 Sep 2011 11:52:14 GMT

haX'i tO Opcitldtlg Web n-prirl. I'irst up. yini PC ii lijsictiim that CTfiflfa j 11 lt ',v object to jiLikr requests u gt die server. This Lump uu to be a hii tricky hi-raitse iliJit ncni brmn'Siii Ikh u diflcren ways hjf rneiiung thijj ihji ci. li i help tiii jui, we've written some proas5eTTi bled JavaScript tbryou. Whenever you the l1 - 1 meum you'll hwv to take some c gt n faith, likr rlii wdr bckjw h i c rcmcs an object to tilsli CijUfstS U ihc-dflMT. Trusi us lllriu li yim'D h'LinL nil...

Dijit API DriveBy Dojo

Mon, 26 Sep 2011 11:45:02 GMT

The functions listed in Table 11-4 are too commonly used not to especially call out. They're available as part of Dijit Base and get pulled in whenever you require Dijit resources into the page. You can also fetch them by issuing a dojo.require dijit. dijit statement, as they are included in the standard build profile, which you'll read more about in Chapter 16. - For comprehensive API documentation, visit Dojo's online documen tation at http api.dojotoolkit.org. Table 11-4. Commonly used Dijit...

Using phpMyAdmin to generate XML Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 11:30:31 GMT

The XML capabilities of phpMyAdmin are very basic, but they're worth knowing about if you need a quick and easy way to generate a static XML document. You can export data from a single table or from several tables. The structure always looks like this lt DatabaseName gt lt TableName gt lt TableName gt lt DatabaseName gt The name of the table becomes the repeating element that contains each record, and the column names make it easy to identify the data you want to use. The XML that phpMyAdmin...

The UserContainer and ApplicationContainer Classes StrutsFramework

Mon, 26 Sep 2011 11:13:19 GMT

I've mentioned the UserContainer and ApplicationContainer classes in previous chapters without defining exactly what they are. These two classes are not part of the Struts framework I created them as part of the example Storefront application. The purpose of these classes is to store user and application-specific information in instances of these classes, rather than in the HttpSession and ServletContext objects, respectively. One of the problems with storing data in the HttpSession is that the...

Introducing the ASPNET AJAX Architecture Server Controls 3

Mon, 26 Sep 2011 11:12:49 GMT

The ASPNET AJAX architecture, which is illustrated in Figure 2-5, consists of two major pieces. First is the Microsoft AJAX Library, which makes developing the client-side functionality of AJAX web applications easier and less time consuming. It has core classes that extend JavaScript to support object-oriented OO scripting represented by the Core Services block. It also consists of a base class library, which provides classes that offer extended error handling among other things. There is a...

Microsoft Silverlight at a Glance AspnetAjax

Mon, 26 Sep 2011 10:51:07 GMT

The quest for an RIA environment is the result of the inherent limitations of the AJAX approach. AJAX solves many issues and can definitely make for smoother and better received Web applications. AJAX, however, is based on HTML and JavaScript. The difference between a classic Web plus AJAX application and an RIA is found in the quality and capabilities of the user interface and the programming power. An RIA offers a new delivery format for Silverlight, it's the Windows Presentation Foundation...

Themes Dojo

Mon, 26 Sep 2011 10:44:15 GMT

A Dijit theme is a fully consistent collection of CSS rules that span across the entire set of widgets. To say that another way, you might think of Dijit as being skinnable, where a theme is a kind skin that you apply. If you need to pull some widgets off the shelf and put together something quickly, themes are especially good because CSS becomes one less thing that you have to worry about implementing. As of version 1.1, Dojo includes three great-looking, prepackaged themes Predominantly light...

Using getBoundingClientRect JavaScriptReference

Mon, 26 Sep 2011 10:34:36 GMT

lt title gt getClientRects and getBoundClientRect Methods lt titl lt script type text javascript gt function hilite var hTop, hLeft, hRight, hBottom, hWidth var select document.forms 0 .choice var n var clientRects var mainElem if n gt 0 amp amp n lt clientRects.length if document.forms 0 .fullWidth.checked hLeft mainElem.getBoundingClientRect .left hRight mainElem.getBoundingClientRect .right else hLeft clientRects n .left hRight clientRects n .right clientRects n .top document.body.scrollTop...

Host Security SecuringAjax

Mon, 26 Sep 2011 10:16:17 GMT

Image your web server as a gladiator about to go into battle. If it's going to have any chance of survival it must be battle ready. Basically, you want something more like Russell Crowe and less like Mel Brooks. Additionally, the server should be hardened as though there were no firewall on the network. Firewalls, such as in the case of port 80, are not a silver bullet. Servers behind firewalls can still be compromised. So, each server needs to look after and take care of itself. In the...

Writing the Application Deployment Descriptor Google Web Toolkit

Mon, 26 Sep 2011 10:04:31 GMT

When you are creating the deployment descriptor, you will need to map each individual GWT-RPC servlet to a URL. This can be done in the same manner as we saw previously when we looked at the deployment descriptor used by the GWT development environment. The easiest way to explain this is to provide an example, then explain it. In listing 16.8 we provide the deployment descriptor file that could be used to deploy the Server Status project from chapter 10. In most cases you can simply copy the...

Relocating the JavaScript Code Google Web Toolkit

Mon, 26 Sep 2011 09:48:22 GMT

If you have been following along and removing the unused files from the sample project, you will see that there aren't many files left. Figure 16.5 shows the current file list for our project. What is left is the project HTML file HelloWorld.html , the gwt.js file, the one loader script ending in .nocache.html, and the four browser specific script files ending in .cache.html. We could deploy this lump of files as-is without any further organization, but if you are deploying your GWT project...

Creating user accounts for MySQL Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 09:47:35 GMT

At the moment, your installation of MySQL has only one registered user the superuser account called root, which has complete control over everything. A lot of beginners think that once they have set up a password for the root user, they can start building databases. This is a big mistake. The root user should never be used for anything other than administration. MySQL stores all databases in a common directory. So, on shared hosting, your database with all its precious information rubs...

ondrag ondragend ondragstart JavaScriptReference

Mon, 26 Sep 2011 09:40:58 GMT

Compatibility WinIE5 , MacIE-, NN-, Moz-, Safari 1.3 The ondrag event fires after the ondragstart event and continues firing repeatedly while the user drags a selection or object onscreen. Unlike the onmousemove event, which fires only as the cursor moves onscreen, the ondrag event continues to fire even when the cursor is stationary In the WinIE5 Safari 1.3 , users can drag objects to other browser windows or other applications. The event fires while the dragging extends beyond the browser...

Validating a single checkbox with Spry Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 09:17:41 GMT

A common requirement on forms is a checkbox to confirm that the user agrees with certain terms and conditions. Creating this with Dreamweaver couldn't be simpler. If you already have the checkbox in your form, select it, and click the Spry Validate Checkbox button on the Insert bar. Save the page to copy the external JavaScript file and style sheet to your Spry assets folder. If you don't have a checkbox, position your cursor where you want it to go inside the form, and click the Spry Validate...

Drawbacks of Continuations Reverse Ajax 2

Mon, 26 Sep 2011 09:07:04 GMT

Measurements of Jetty's Comet performance by WebTide developer Greg Wilkins reveal what a major difference continuations can make. In Wilkins's test, generating 10,600 concurrent requests without continuations caused Jetty to spawn 10,600 threads, with a consumption of 694MB of stack memory. Enabling continuations in the same scenario allowed Jetty to service the same number of requests with only 875 threads and 57MB of stack memory, while still servicing 5,000 requests per second. Clearly,...

Quiz Hzq Scriptmanager

Mon, 26 Sep 2011 08:57:54 GMT

1. What is the difference between localization and globalization 2. What is the role of the ScriptManager control in implementing multilingual applications 3. What is the purpose of the EnableScriptGlobalization property 4. Name the namespaces in the .NET library that provide support for globalization and localization. 5. Define the terms script localization and script globalization. 1. Although the terms localization and globalization seem synonymous, there are distinct differences between the...

Example Rendering a Tiles definition in a JSP page AjaxStruts

Mon, 26 Sep 2011 08:57:42 GMT

lt taglib prefix-'tiles gt lt tiles insert definition mainLayoutDef gt lt tiles put name title type string value-'Start Page gt lt tiles put name body lt tiles insert gt Here's another JSP page view_page_one.jsp that uses the same definition lt taglib prefix-'tiles gt lt tiles insert definition mainLayoutDef gt lt tiles put name title type string value Page One gt lt tiles put name body lt tiles insert gt With Tiles, you reduce the amount of HTML that you have to cut and paste. More...

To handle menu events AdobeAIR

Mon, 26 Sep 2011 08:45:02 GMT

1. Open Script 7.1 in your text editor or IDE, if it is not already. Throughout this entire chapter you'll continue to build on this one example until it's fully functional or reasonably so . 2. Anywhere within the JavaScript, define a function that should be called when the user selects File gt Exit Script 7.2 function doExit e lt html gt lt -- Script 7.2 -- gt lt head gt lt title gt Menu Events lt title gt lt script type text javascript lt script Function for handling the Exit menu item...

Isolated Storage AspnetAjax

Mon, 26 Sep 2011 08:40:15 GMT

Nearly all applications greatly benefit from local data storage. By local storage, I mean the application's ability to save some data on the client machine. This has never been an issue for desktop applications, which have full access to the local disk and file system. For Web applications, though, it has always been a mission-impossible task. For security reasons, any code hosted by Web pages typically, JavaScript code can't just access the file system of the local machine. For years, Web page...

scriptsLoadComplete Server Controls 2

Mon, 26 Sep 2011 08:26:03 GMT

Recall from Listing 24-23 that the current _ScriptLoaderTask instance invokes the _completedCallback delegate after loading all the scripts. Also recall that this delegate represents the _scriptsLoadComplete method of the current PageRequestMananger instance. Listing 24-24 presents the internal implementation of the _scriptsLoadComplete method. This method first calls the scrollTo method on the window object to set the scroll position this._scrollPosition.y Next, this method invokes the...

Summary Gtx Google Web Toolkit

Mon, 26 Sep 2011 08:17:40 GMT

JSNI is an extremely powerful way of interfacing with existing JavaScript libraries and for filling in the gaps where GWT might not yet have the functionality you need. It allows us to apply some of the good control and typing aspects of Java to our JavaScript interfaces however, we should keep the use of JavaScript as a minimum. View using JSNI as you would writing assembly language code segments in a high-level language project it is for specialized tasks, not for every day use. Indeed, the...

OnLoad Server Controls 2

Mon, 26 Sep 2011 07:59:54 GMT

As you can see from Listing 17-15, the TextBoxWatermarkExtenderControl server control overrides the OnLoad method of its base class to perform the following tasks. First, it invokes the OnLoad method of its base class to raise the Load event and consequently to invoke all the event handlers registered for the Load event of the TextBoxWatermarkExtenderControl To understand what the rest of the code in the OnLoad method does, you need to revisit Listing 17-14 as repeated in Listing 17-16. Recall...

The RequiredFieldValidator ASP NET with AJAX

Mon, 26 Sep 2011 07:24:01 GMT

The RequiredFieldValidator ensures the user provides a value for your control, or in the case of drop drop-down lists, that the user picks something other than the default value. To get started, create a new web site called RequiredFieldValidator. In this section, you're going create the shipping selection web page shown in Design view in Figure 5-1. This is a pretty standard shipping form, as you can see on any number of web sites. You can imagine how you'd incorporate such a page into your...

Repeater Control Event Management AJAXComponents

Mon, 26 Sep 2011 06:58:36 GMT

Repeater exposes an ItemCommand event, an ItemCreated event, and an ItemDataBound event. We use the Events collection provided by System.Web.UI.Control to track registered client delegates. The following code for the ItemCommand event is reproduced in a similar manner for the ItemCreated and ItemDataBound events private static readonly object ItemCommandKey new object public event RepeaterCommandEventHandler ItemCommand Events.AddHandler ItemCommandKey, value Events.RemoveHandler...

SON and JSONRPC JavascriptCode

Mon, 26 Sep 2011 06:47:38 GMT

In the next few chapters, we'll introduce you to four server-side web application development frameworks and the different strategies they employ for integrating Ajax techniques into their workflow. Before we get there, we need to stop and look at the integration that's sweeping the nation, JavaScript Object Notation JSON . 1SON is an open format describing how to represent 1avaScript objects in a simple text representation that can be easily created and parsed. In other words, you can send...

Installing MySQL on Windows Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 06:14:29 GMT

MySQL comes in a range of versions, but the one you should choose is Windows Essentials. It contains all the important stuff and certainly everything you need for this book. If you have a version older than MySQL 4.1.5 already installed on your computer, you must unin-stall the old version first. Deciding whether to enable InnoDB support MySQL is capable of storing database tables in a variety of formats. Most of the time, you don't need to worry about this. The default MySQL format, MyISAM, is...

Info Gfn AjaxApplications

Mon, 26 Sep 2011 06:13:03 GMT

var key.className notes i musicalButton key.note notes i key.onmouseover playNote el.appendChild key function playNote event var note this.note console.innerHTML note - Previously, we had defined our key sequence in the HTML. Now it is defined as a global JavaScript array. The assignKeys method examines all the top-level DIV tags in the document, to see if the className contains the value musicalKeys. If it does, then it tries to populate that DIV with a working keyboard, using the makeKeyboard...

onhelp JavaScriptReference

Mon, 26 Sep 2011 05:07:25 GMT

Compatibility WinIE4 , MacIE5 , NN-, Moz-, Safari- The onhelp event handler fires in Windows whenever an element of the document has focus and the user presses the F1 function key on a Windows PC. As of MacIE5, the event fires only on the window in other words, event handler specified in the lt body gt tag and does so via the dedicated Help key on a Mac keyboard. Browser Help menu choices do not activate this event. To prevent the browser's Help window from appearing, the event handler must...

Weather Widget EventHandling

Mon, 26 Sep 2011 05:00:37 GMT

This tool illustrates three aspects of th Aj - Entering a rip cofe can weather senrice t feteh the e conditions. This illustrates the multiple a r as of the page in Current Condition, Noon, St the Mrtrather.com Fea t red L are aU updated from a tingle Cinematic Effects Transition Ente up facep ate to the w animated text movement, dk a ordk gt n are all IMuAitln library. Gehavtor The accordion i cn Accordion behavior to a set of a rea j. that get populated afte weather data, completes The...

Applying a dynamic value to a radio group Dreamweaver CS3 Ajax

Mon, 26 Sep 2011 04:46:47 GMT

The Administrator radio buttons still don't respond to the changes. We'll fix that next. Continue working with register_user.php from the previous section. 1. When any errors are detected, you need checked checked to be inserted in the tag of the radio button that the user selected. Since the radio group is called admin_priv, the value you want is contained in _POST 'admin_priv' . Although you can type this directly into the Dynamic Radio Group dialog box, Dreamweaver lets you define _POST,...

Submission Throttling AjaxWidget

Mon, 26 Sep 2011 04:42:42 GMT

Predictive Fetch is one pattern for retrieving data from the server the other side of an Ajax solution is the sending of data to the server. Since you want to avoid page refreshes, the question of when to send user data is important. In a traditional web site or web application, each click makes a request back to the server so that the server is always aware of what the client is doing. In the Ajax model, the user interacts with the site or application without additional requests being...

The ScriptManagerProxy ControlAdding Scripts and Services Scriptmanager

Mon, 26 Sep 2011 04:38:34 GMT

The documentation at the ASP.NET Ajax site states, ScriptManagerProxy control enables you to add scripts and services that are specific to nested components. Note that you can use this control only to add scripts or services that have been predefined by the ScriptManager control. However, you cannot remove these scripts using this control. In other words, you can use this control to add scripts and services to your web page, which already has a ScriptManager control inside. The following code...

Using the UpdatePanel Control Server Controls 3

Mon, 26 Sep 2011 04:14:33 GMT

To use an UpdatePanel control, you simply drag and drop it onto the design surface of your web form see Figure 5-5 . Figure 5-5. Placing an UpdatePanel control on a web form Figure 5-5. Placing an UpdatePanel control on a web form However, as you know, the UpdatePanel control cannot function without a ScriptManager control on the page. Additionally, the ScriptManager control must be located before any UpdatePanel controls on your page. In other words, as you read your source code from top to...

To create a fullscreen window AdobeAIR

Mon, 26 Sep 2011 04:11:54 GMT

1. In your project's HTML file, begin a new JavaScript function Script 6.6 lt script type text javascript gt function makeFullScreenO 2. Within the makeFullScreenO function, change the stage. displayState property window.nativeWindow.stage. This rather verbose line is all you need to enable full-screen mode. 3. Within the makeFullScreenO function, change the HTML button document.getElementById 'btn' . onclick makeNormalScreen document.getElementById 'btn' . innerHTML 'Normal or press The HTML...

To create a fullscreen window ApplicationSandbox

Mon, 26 Sep 2011 04:11:04 GMT

1. In your project's HTML file, begin a new JavaScript function Script 6.6 lt script type text javascript gt function makeFullScreenO 2. Within the makeFullScreenO function, change the stage, display State property window.nativeWindow.stage. display.StageDisplayState. - FULL.SCREEN This rather verbose line is all you need to enable full-screen mode. 3. Within the makeFullScreenO function, change the HTML button document.getElementByldC'btn1 . onclick makeNormalScreen...