Improve your life Through Science and Art: framework

Showing posts with label framework. Show all posts

Saturday, September 20, 2014

NetBeans: 8.0.1 Released with bunch of out-of-the-box tools = productivity++

In every NetBeans release it provides out-of-the-box tools that leverage the java standards and other tools toward the web standards, alongside great papular market tools that increases developer daily productivity.

NetBeans editor analyzes code to work efficiently with great tips and refactoring templates for more clear and cleaner code, provides migration from other JDKs toward Java 8, and it works for Java SE 8, Java SE Embedded 8, and Java ME Embedded 8.

The IDE also has a range of new enhancements that further improve its support for Maven and Java EE with PrimeFaces; new tools for HTML5, in particular for AngularJS; and improvements to PHP and C/C++ support.

Beside that the IDE has an interesting new features especially for JavaScript developers whom seeks for writing modular code, it comes with built-in support RequireJS, that provides modularity and enterprise features for JavaScript.

More interesting features:

You can now debug your JavaScript files with Karma.
Node.JS and Bower built-in integrations let you install modules directly within the IDE.
Support for latest application servers GlassFish 4.1, Tomcat 8.0.9, WildFly 9, and WebLogic 12.1.3
IDE comes with pre-bundled GlassFish 4.1 and Tomcat 8.0.9
Latest PrimeFaces v5.0 framework bundled with IDE.
Improved Git support

GlassFish 4.1 is now Java SE 8 certified, so you can develop your Java EE 7 projects with JDK 8 for more modularity and cleaner code, yeah have fun :)

For the complete set of bunch of tools please visit NetBeans IDE 8.0.1 Information

Hungry to code, so what are you waiting for?? , Download Netbeans IDE

Wednesday, August 14, 2013

Why not jQuery? it is Fast, powerful, cross browsers and easy to use framework.

jQuery, jQuery then jQuery, yeah it simplifies the way you touch the HTML via JavaScript.

On jQuery site, its definition as the following:

jQuery is a fast, small, and feature-rich JavaScript library. It makes things like HTML document traversal and manipulation, event handling, animation, and Ajax much simpler with an easy-to-use API that works across a multitude of browsers. With a combination of versatility and extensibility, jQuery has changed the way that millions of people write JavaScript.

Yes, I agree totally with this statement, I make use of the JavaScript framework, jQuery. jQuery simplifies common tasks and provides a single interface to actions that are implemented inconsistently in different browsers. Perhaps the most common use of jQuery in my development is reading in files (XML, JSON, text …etc) or other data from web services, but it also make it easy for traversing the DOM and applying CCS to components in easy way.

The following section is meant to give a quick introduction to using jQuery, and making your hands dirty with code to get the idea. For advanced features of the framework, you can branch to jQuery documentation and API references.

But, wait here for a second, be patient, before you can use jQuery, you need to include it in your web page. You can do so by downloading the latest version at http://jquery.com/ or by grabbing a Google-hosted version by adding the following to the <head> section of your HTML file:

<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>

As of time of this writing, the latest version of jQuery is 2.0.3, and also there are Other CDNs could be used, and are listed on jQuery home page, I have used here Google one.

After adding the library to your page lets, get in touch with jQuery functionality and development.

Once you have included jQuery in your document, you can use its functions via two global variables: jQuery and its shorthand, $.

Demo page structure:
We will use this page in our journey, for the sake of clarity of how to use jQuery.

<head>

jQuery Example
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>
<style>
.content
{
 padding: 20px;
 width: 200px;
 height: 200px;
 background-color: #CCC;
}

#eventInfo
{
 width: 420px;
 height: 20px;
 background-color: #000;
 color: #CCC;
 font-weight: bold;
 margin-top: 10px;
}
</style>

</head>
<body>


  



</body>

Query Document Objects
Among its many uses, jQuery is very helpful at quickly and easily extracting elements from your HTML page into JavaScript code. You can query by id, tag name, CSS class, or combinations of these factors. jQuery makes this task easier, so you can focus on what you want to do with those elements.

To grab a single piece of the page, such as the content <div>, you call it by its id. Much of jQuery’s syntax is borrowed from CSS, which may look familiar.

Here is how you would call an object with an id of content:
Notice:
I am using the dollar-sign shorthand. Then I add parentheses because $ is a variable and a function (jQuery stretches the bounds of JavaScript in ways that you and I probably will not). Inside the function, we pass a string with the CSS we would use to style the map div, #content.

Let us see how to add a text to this div content, just use one of the following snippets of code:
Or simple chaining one
You have now used your first jQuery function to query for a specific element and add a text to it. You can achieve the same result with JavaScript’s standard document.getElementById function, but jQuery’s method is faster to type. Plus, the result using $ allows you to chain other jQuery functions, such as visual effects, binding events or applying values and css as we have made in the previous code.

Notice:
Every jQuery function returns a jQuery object wrapping the queried element(s). Therefore, we can use the functions call-chaining mechanism, this pattern is called builder design pattern.

jQuery can also do more than just query individual elements; it can gather multiple elements in a single call. Here are a few examples:
Each of these examples shows a different type of querying—and many more are possible. You can learn about what jQuery calls selectors at http://api.jquery.com/category/selectors/.

Use jQuery to fire browser events
jQuery provides a lean way to use and fires browser events, such as clicking, double clicking or dragging. You can also react to events anywhere in the browser, and jQuery makes reacting a simple process for us.

To respond to an event, you first need to be listening for it. To do so when your page first loads, you register your intention to react to an event. You can do this by adding a JavaScript function to the onload attribute of your <body> tag. Or you can do this with a special jQuery ready event.

Although creating an event to register other events may seem counterintuitive, but believe me it works. Here is an example that waits until the page is ready:
Notice:
That the element we are querying for is a little different from in the past. Instead of a string inside the parentheses, we have inserted a standard JavaScript object, document. When enough of the page has loaded that the browser knows all the objects it contains, we call the register_events function.

That register_events function does not exist, however, so we need to write it. Or, instead, we could react to the same event with an anonymous function:
As with most anonymous functions, you usually want to keep it to just a few lines. If you have many events to register, you are probably best served with a named function.

Note

A big difference exists between using your browser’s onload attribute and jQuery’s ready event. With onload, you wait until the entire page is loaded, including images and other external files. With $(document).ready, you can run code, such as registering events and hiding objects, the moment the browser is ready. Using jQuery here often translates to a better user experience.

Now that you have waited for the browser to be ready to register other events, let us register them. Here is the basic pattern for jQuery events:
The element portion is usually a selector, such as an element’s id (though it can also be any browser object, as shown in the ready example). The event piece is the name of the function, as declared by jQuery. Finally, function is the function reference, either an anonymous function or the name of the function to call.

Here is how you would listen for a particular element to be double clicked:
If you are familiar with JavaScript events included in HTML, you might be wondering where the on, as in onDblClick, went. In jQuery, events are referenced with only the action so it is dblclick.

You can also get additional information about the event. The information available may be a little different depending on the event. Here is how you find out where the user has double-clicked on a page:
I used a dblclick event. Because we want more information about the event, I included an optional parameter e to the anonymous function. Within the function, I can use that variable to get information, such as where the user double clicked. This data comes in two pieces:

The number of pixels from the left side of the page X and the number from the top of the page Y. You can see a sampling of available events in Table 1, along with the additional information that is passed in the optional parameter to each event.

Tip: Try also to double click inside content1 div, at different location and watch how X and Y value changes.
Table 1: Some Useful jQuery Events

Event Name	Objects Available	Additional Information
click	Any	Page location: pageX, pageY
dblclick	Any	Page location: pageX, pageY
mousemove	Any	Page location: pageX, pageY
keydown	document, window	Key code
focus	Form elements

Events will make your web pages much more interactive. For a full list of events (and additional event information available), see jQuery’s documentation at http://api.jquery.com/category/events/.

Insert and Hide Content

Once you have one or more elements from the page using jQuery, you need to do something to them. Here, I will show you a way to add or replace the content inside a page element. In addition, I will also demonstrate an effect that will hide the content, so later, you can make it reappear.

Let us say you want an element on your page where you can show the event information raised from previous double click event such as event type and the event source id. You can add the element with HTML using something like this:
When you are ready to add the event information, you can use jQuery to find the element and then display the event information. If you want to display the content of a variable called info, you could use this single line of jQuery:
This line will find the element on the page with the id of eventInfo and then replace its inner HTML with the value in the info variable. If you just want to add additional content to the element, use this line instead:
Alternatively, use can use chaining feature as the following.
Now the eventInfo div content will look something like this:

Event Info: Event type is: dblclick, raised from: content1

You have seen how to insert content, but what about making that same content disappear? For example, before adding the event Information, a page with just Results: without anything after it looks a bit funny. So when the page loads, run the following code to hide the results element:
Moreover, when you are ready to display the results to the user, include this code:
On the other hand, append it to the last of your chaining command as the following:
These two functions are simple (and very useful) examples of jQuery effects. Many more effects are listed on the jQuery website at http://api.jquery.com/category/effects/.

Final code



jQuery Example
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>
<style>
.content
{
 padding: 20px;
 width: 200px;
 height: 200px;
 background-color: #CCC;
}

#eventInfo
{
 width: 420px;
 height: 20px;
 background-color: #000;
 color: #CCC;
 font-weight: bold;
 margin-top: 10px;
}
</style>
<script type="text/javascript" language="javascript">
   //Use ready function to execute all code after browser parse and build DOM tree.
   $(document).ready(function(e) {
     
  // Hideing div with id eventInfo
  $('#eventInfo').hide(); 
  
  // Setting dive text and applying css value for the text to be of color red
  $('#content').text('My name is Mohamed Taman').css('color','red').append('

');
  
   //Get the first span wrapped inside the div with css class 'content' and set its text 
  $('.content span:first').text('Number of divs in the document are: ' + $('div').length);
  
  
  // Register div with id content1 to double click event
  $('#content1').dblclick(function(e) {
        alert('I am double clicked with and event location at, X: '+ e.pageX +', and Y: '+ e.pageY);
 
  var info = 'Event type is: '+ e.type +', raised from: '+ e.target.id;

  $('#eventInfo').html('Event Info: ').append(info).show();
    });
});
</script>

<body>


  



</body>

Let's wrap up

By now, we have reached to the end of the article, and I hope you enjoyed and find it useful.

In the next part, I will demonstrate an important issue, which is loading and reading data files using jQuery either it is JSON or XML data files. So If you want to interact with data outside of your current HTML file, jQuery has some excellent tools for doing these sorts of Ajax calls. Though Ajax is short for Asynchronous JavaScript And XML, you can access any type of data with Ajax.

Friday, July 27, 2012

EL: Expression language 2.2 Distilled

Here I will give a brief introduction and also some improvement done in JSR 245, The Expression Language (also referred to as the EL),
which provides an important mechanism for enabling the presentation layer (web pages) to communicate with the application logic (managed beans).

The EL is used by both JavaServer Faces technology and JavaServer Pages (JSP) technology.

The EL represents a union of the expression languages offered by JavaServer Faces technology and JSP technology.

The EL allows page authors to use simple expressions to dynamically access data from JavaBeans components.

For example, the test attribute of the following conditional tag is supplied with an EL expression that compares 0 with the number of items in the session-scoped bean named cart.

JavaServer Faces technology uses the EL for the following functions:

Deferred and immediate evaluation of expressions.
The ability to set as well as get data.
The ability to invoke methods.

To summarize, the EL provides a way to use simple expressions to perform the following tasks:

Dynamically read application data stored in JavaBeans components, various data structures, and implicit objects.
Dynamically write data, such as user input into forms, to JavaBeans components.
Invoke arbitrary static and public methods.
Dynamically perform arithmetic operations.

The EL is also used to specify the following kinds of expressions that a custom tag attribute will accept:

Immediate evaluation expressions or deferred evaluation expressions. An immediate evaluation expression is evaluated at once by the underlying technology, such as JavaServer Faces.

A deferred evaluation expression can be evaluated later by the underlying technology using the EL.
Value expression or method expression. A value expression references data, whereas a method expression invokes a method.
Rvalue expression or lvalue expression. An rvalue expression can only read a value, whereas an lvalue expression can both read and write that value to an external object.

Immediate and Deferred Evaluation Syntax
---------------------------------------------------
The EL supports both immediate and deferred evaluation of expressions. Immediate evaluation means that the expression is evaluated and the result returned as soon as the page is first rendered.

Deferred evaluation means that the technology using the expression language can use its own machinery to evaluate the expression sometime later during the page’s lifecycle, whenever it is appropriate to do so, because of its multiphase lifecycle, JavaServer Faces technology uses mostly deferred evaluation expressions.

Those expressions that are evaluated immediately use the ${} syntax. Expressions whose evaluation is deferred use the #{} syntax.

Immediate Evaluation
----------------------------
All expressions using the ${} syntax are evaluated immediately. These expressions can be used only within template text or as the value of a tag attribute that can accept runtime expressions.

The following example shows a tag whose value attribute references an immediate evaluation expression that gets the total price from the session-scoped bean named cart:

The JavaServer Faces implementation evaluates the expression ${sessionScope.cart.total}, converts it, and passes the returned value to the tag handler.

Immediate evaluation expressions are always read-only value expressions. The preceding example expression cannot set the total price, but instead can only get the total price from the cart bean.
Deferred Evaluation
-----------------------
Deferred evaluation expressions take the form #{expr} and can be evaluated at other phases of a page lifecycle as defined by whatever technology is using the expression. In the case of JavaServer Faces technology, its controller can evaluate the expression at different phases of the lifecycle, depending on how the expression is being used in the page.

The following example shows a JavaServer Faces h:inputText tag, which represents a text field component into which a user enters a value. The h:inputText tag’s value attribute references a deferred evaluation expression that points to the name property of the customer bean:

For an initial request of the page containing this tag, the JavaServer Faces implementation evaluates the #{customer.name} expression during the render-response phase of the lifecycle.

During this phase, the expression merely accesses the value of name from the customer bean, as is done in immediate evaluation.

For a postback request, the JavaServer Faces implementation evaluates the expression at different phases of the lifecycle, during which the value is retrieved from the request, validated, and propagated to the customer bean.

As shown in this example, deferred evaluation expressions can be:
- Value expressions that can be used to both read and write data.
- Method expressions.
Value expressions (both immediate and deferred) and method expressions are explained in the next section.

Value and Method Expressions
--------------------------------------
The EL defines two kinds of expressions: value expressions and method expressions. Value expressions can either yield a value or set a value. Method expressions reference methods that can be invoked and can return a value.

Value Expressions
--------------------------
Value expressions can be further categorized into rvalue and lvalue expressions. Rvalue expressions can read data but cannot write it. Lvalue expressions can both read and write data.

All expressions that are evaluated immediately use the ${} delimiters and are always rvalue expressions. Expressions whose evaluation can be deferred use the #{} delimiters and can act as both rvalue and lvalue expressions. Consider the following two value expressions:

The former uses immediate evaluation syntax, whereas the latter uses deferred evaluation syntax. The first expression accesses the name property, gets its value, adds the value to the response, and gets rendered on the page. The same can happen with the second expression. However, the tag handler can defer the evaluation of this expression to a later time in the page lifecycle, if the technology using this tag allows.

In the case of JavaServer Faces technology, the latter tag’s expression is evaluated immediately during an initial request for the page. In this case, this expression acts as an rvalue expression. During a postback request, this expression can be used to set the value of the name property with user input. In this case, the expression acts as an lvalue expression.

Method Expressions
----------------------------
Another feature of the EL is its support of deferred method expressions. A method expression is used to invoke an arbitrary public method of a bean, which can return a result.

In JavaServer Faces technology, a component tag represents a component on a page. The component tag uses method expressions to invoke methods that perform some processing for the component. These methods are necessary for handling events that the components generate and for validating component data, as shown in this example:

The h:inputText tag displays as a text field. The validator attribute of this h:inputText tag references a method, called validateName, in the bean, called customer.

Because a method can be invoked during different phases of the lifecycle, method expressions must always use the deferred evaluation syntax. Like lvalue expressions, method expressions can use the (.) and the ([]) operators.

For example,
#{object.method} is equivalent to #{object["method"]}. The literal inside the [] is converted to String and is used to find the name of the method that matches it. Once the method is found, it is invoked, or information about the method is returned.

Parameterized Method Calls
------------------------------------
The EL offers support for parameterized method calls.Method calls can use parameters without having to use static EL functions.

Both the . and [] operators can be used for invoking method calls with parameters, as shown in the following expression syntax:

expr-a[expr-b](parameters)
expr-a.identifier-b(parameters)

In the first expression syntax, expr-a is evaluated to represent a bean object. The expression expr-b is evaluated and cast to a string that represents a method in the bean represented by expr-a. In the second expression syntax, expr-a is evaluated to represent a bean object, and identifier-b is a string that represents a method in the bean object. The parameters in parentheses are the arguments for the method invocation. Parameters can be zero or more values or expressions, separated by commas.

Parameters are supported for both value expressions and method expressions. In the following example, which is a modified tag from the guessnumber application, a random number is provided as an argument rather than from user input to the method call:

The preceding example uses a value expression.

Consider the following example of a JavaServer Faces component tag that uses a method expression:

The EL expression trader.buy calls the trader bean’s buy method. You can modify the tag to pass on a parameter.Here is the revised tag where a parameter is passed:

In the preceding example, you are passing the string ’SOMESTOCK’ (a stock symbol) as a parameter to the buy method.

Literal Expressions
-------------------------
A literal expression is evaluated to the text of the expression, which is of type String. A literal expression does not use the ${} or #{} delimiters.

If you have a literal expression that includes the reserved ${} or #{} syntax, you need to escape these characters as follows:

By creating a composite expression as shown here:
- ${’${’}exprA}
- #{’#{’}exprB}
The resulting values would then be the strings ${exprA} and #{exprB}.
By using the escape characters \$ and \# to escape what would otherwise be treated as an eval-expression:
- \${exprA}
- \#{exprB}

The resulting values would again be the strings ${exprA} and #{exprB}. When a literal expression is evaluated, it can be converted to another type.

Literal expressions can be evaluated immediately or deferred and can be either value or method expressions. At what point a literal expression is evaluated depends on where it is being used. If the tag attribute that uses the literal expression is defined to accept a deferred value expression, when referencing a value, the literal expression is evaluated at a point in the lifecycle that is determined by other factors, such as where the expression is being used and to what it is referring.

In the case of a method expression, the method that is referenced is invoked and returns the specified String literal.

Refrences:
--------------

For more information on the updated EL, see http://uel.java.net/.
See Section 1.18 of the JavaServer Pages 2.2 Expression Language specification (available from http://jcp.org/aboutJava/communityprocess/final/jsr245/) for the complete type conversion rules.

Saturday, July 21, 2012

JSF: The JavaServer Faces Technology

JavaServer Faces Technology

JavaServer Faces technology is a server-side component framework for building Java technology-based web applications.

JavaServer Faces technology consists of the following:
--------------------------------------------------------------------

An API for representing components and managing their state; handling events, server-side validation, and data conversion; defining page navigation; supporting internationalization and accessibility; and providing extensibility for all these features.
Tag libraries for adding components to web pages and for connecting components to server-side objects JavaServer Faces technology provides a well-defined programming model and various tag libraries. These features significantly ease the burden of building and maintaining web applications with server-side user interfaces (UIs). With minimal effort, you can complete the following tasks.
- Create a web page.
- Drop components onto a web page by adding component tags.
- Bind components on a page to server-side data.
- Wire component-generated events to server-side application code.
- Save and restore application state beyond the life of server requests.
- Reuse and extend components through customization.

What Is a JavaServer Faces Application?
--------------------------------------------------

The functionality provided by a JavaServer Faces application is similar to that of any other Java web application. A typical JavaServer Faces application includes the following parts:

A set of web pages in which components are laid out.
A set of tags to add components to the web page.
A set of managed beans, which are lightweight container-managed objects (POJOs) with minimal requirements. They support a small set of basic services, such as resource injection, lifecycle callbacks and interceptors.
A web deployment descriptor (web.xml file).
Optionally, one or more application configuration resource files, such as a faces-config.xml file, which can be used to define page navigation rules and configure beans and other custom objects, such as custom components.
Optionally, a set of custom objects, which can include custom components, validators, converters, or listeners, created by the application developer.
A set of custom tags for representing custom objects on the page.

Figure 1 shows the interaction between client and server in a typical JavaServer Faces application. In response to a client request, a web page is rendered by the web container that implements JavaServer Faces technology.

Figure 1: Responding to a Client Request for a JavaServer Faces Page.

The web page, index.xhtml, is built using JavaServer Faces component tags. Component tags are used to add components to the view (represented by helloUI in the diagram), which is the server-side representation of the page. In addition to components, the web page can also reference objects, such as the following:

Any event listeners, validators, and converters that are registered on the components.
The JavaBeans components that capture the data and process the application-specific functionality of the components.

On request from the client, the view is rendered as a response. Rendering is the process whereby, based on the server-side view, the web container generates output, such as HTML or XHTML, that can be read by the client, such as a browser.

JavaServer FacesTechnology Benefits
----------------------------------------------

One of the greatest advantages of JavaServer Faces technology is that it offers a clean separation between behavior and presentation for web applications. A JavaServer Faces application can map HTTP requests to component-specific event handling and manage components as stateful objects on the server. JavaServer Faces technology allows you to build web applications that implement the finer-grained separation of behavior and presentation that is traditionally offered by client-side UI architectures.

The separation of logic from presentation also allows each member of a web application development team to focus on a single piece of the development process and provides a simple programming model to link the pieces. For example, page authors with no programming expertise can use JavaServer Faces technology tags in a web page to link to server-side objects without writing any scripts.

Another important goal of JavaServer Faces technology is to leverage familiar component and web-tier concepts without limiting you to a particular scripting technology or markup language. JavaServer Faces technology APIs are layered directly on top of the Servlet API, as shown in Figure 2.

Figure 2: Java Web Application Technologies.

This layering of APIs enables several important application use cases, such as using different presentation technologies, creating your own custom components directly from the component classes, and generating output for various client devices.

Facelets technology, available as part of JavaServer Faces 2.0, is now the preferred presentation technology for building JavaServer Faces technology-based web applications.

Facelets technology offers several advantages:

Code can be reused and extended for components through the templating and composite component features.
When you use the JavaServer Faces Annotations feature, you can automatically register the managed bean as a resource available for JavaServer Faces applications. In addition, implicit navigation rules allow developers to quickly configure page navigation. These features reduce the manual configuration process for applications.
Most important, JavaServer Faces technology provides a rich architecture for managing component state, processing component data, validating user input, and handling events.

For more information on JavaServer Faces technology, see:
---------------------------------------------------------------------------

JavaServer Faces 2.0 specification: http://jcp.org/en/jsr/detail?id=314
JavaServer Faces project web site: http://javaserverfaces.java.net/
Mojarra (JavaServer Faces 2.0 implementation) Release Notes: http://javaserverfaces.java.net/nonav/rlnotes/2.1.4/

Wednesday, June 6, 2012

ADF: How to use an af:popup during long running tasks?

For long-running tasks in your application, a pop-up message window can be raised to alert the users that the specific task may take a while.

This can be accomplished using a combination of ADF Faces components (af:popup and af:dialog) and some JavaScript code.

In this recipe, we will initiate a long-running task in a managed bean, and raise a pop-up for the duration of the task to alert us to the fact that this operation may take a while. We will hide the pop-up once the task completes.

Getting ready
----------------
You will need to create a skeleton Fusion Web Application (ADF) workspace before you proceed with this recipe.

How to do it
--------------

Create a new JSF page called longRunningTask.jsf based on any of the quick start layouts.

Drop a Button (af:commandButton) component from the Component Palette to the page.
You may need to surround the button with an af:toolbar component. Using the Property Inspector, change the button's Text property to Long Running Task and set its PartialSubmit property to true.

Create an action listener for the button by selecting Edit… from the Property Menu next to the ActionListener property in the Property Inspector. Create a new managed bean called LongRunningTaskBean and a new method called longRunningTask.

Edit the LongRunningTaskBean Java class and add the following code to the longRunningTask() method:

Return to the longRunningTask.jsf page editor. Right-click on the af:commandButton in the Structure window and select Insert Inside af:commandButton | ADF Faces….

From the Insert ADF Faces Item dialog, select Client Listener. In the Insert Client Listener dialog, enter longRunningTask for the Method field and select action for the Type field.

Add an af:resource to the af:document tag.
Make sure that the af:resource type attribute is set to javascript and add the following JavaScript code inside it:

Finally, add a Popup (af:popup) ADF Faces component to the page with an embedded Dialog (af:dialog) component in it.
Ensure that the pop-up identifier is set to longRunningPopup and that its ContentDelivery attribute is set to immediate.
Also add an af:outputText component to the dialog with some text indicating a long running process.
Your pop-up should look similar to the following:

Here is the complete code for the backing bean:

And jsf page:

How it works
--------------
In steps 1 and 2, we created a JSF page called longRunningTask.jsf and added a button component to it. When pressed, the button will initiate a long-running task through an action listener. The action listener is added to the button in steps 3 and 4. It is defined to a method called longRunningTask() in a managed bean. The implementation of longRunningTask() simply waits for 5 seconds (step 4). We have also ensured (in step 2) that the button component's partialSubmit property is set to true. This will enable us to call the clientListener method that is added in steps 5 and 6.

In steps 5 and 6, we defined a clientListener for the button component. The client listener is implemented by the longRunningTask() JavaScript method, added to the page in step 6. The longRunningTask() JavaScript method adds a busy state listener for the pop-up component (the pop-up itself is added to the page in step 7) by calling addBusyStateListener() and prevents any user input by calling preventUserInput() on the JavaScript event. The busy state listener is implemented by the JavaScript method busyStateListener(). In it, we hide the pop-up and remove the busy state listener once the event completes.

Finally, in step 7, we added the longRunningPopup pop-up to the page. The pop-up is raised by the busyStateListener() as long as the event is busy (for 5 seconds). We made sure that the pop-up's contentDelivery attribute was set to immediate to deliver the pop-up content immediately once the page is loaded.

To test the recipe, right-click on the longRunningTask.jsf page in the Application Navigator and select Run or Debug from the context menu. When you click on the button, the pop-up is raised for the duration of the long-running task (the action listener in the managed bean). The pop-up is hidden once the long-running task completes.

Saturday, May 26, 2012

JDK7: JavaBean enhancements in Java 7

JavaBean is a way of building reusable components for Java applications. They are Java classes that follow certain naming conventions. There have been several JavaBean enhancements added in Java 7. Here we will focus on the java.beans.Expression class, which is useful in executing methods. The execute method has been added to facilitate this capability.

Getting ready
-----------------
To use the Expression class to execute a method:

Create an array of arguments for the method, if needed.
Create an instance of the Expression class specifying the object that the method is to be executed against, the method name, and any arguments needed.
Invoke the execute method against the expression.
Use the getValue method to obtain the results of the method execution, if necessary.

How to do it...
-------------------

1. Create a new console application. Create two classes: JavaBeanExample, which contains the main method and a Person class. The Person class contains a single field for a name along with constructors, a getter method, and a setter method:

2. In the main method of the JavaBeanExample class, we will create an instance of the Person class, and use the Expression class to execute its getName and setName methods:

3. Execute the application. Its output should appear as follows:

Name: Taman
Name: Mohamed
Name: Mohamed
getValue: Mohamed

How it works...
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The Person class used a single field, name. The getName and setName methods were used from the main method, where a Person instance was created. The Expression class' constructor has four arguments. The first argument was not used in this example, but can be used to define a return value for the method executed. The second argument was the object that the method would be executed against. The third argument is a string containing the name of the method, and the last argument was an array containing the parameters used by the method.

In the first sequence, the setName method was executed using an argument of Mohamed. The output of the application shows that the name was initially Taman, but was changed to Mohamed after the execute method was executed.

In the second sequence, the getName method was executed. The getValue method returns the results of the execution of the method. The output shows that the getName method returned Mohamed.

There's more...
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There have been other enhancements to the classes of the java.bean package. For example, the toString method has been overridden in the FeatureDescriptor and PropertyChangeEvent classes to provide a more meaningful description.

The Introspector class provides a way of learning about the properties, methods, and events of a Java Bean without using the Reflection API, which can be tedious. The class has added a getBeanInfo method, which uses the Inspector class' control flags to affect the BeanInfo object returned.

The Transient annotation has been added to control what is included. A true value for the attribute means that the annotated feature should be ignored.

A new constructor has been added to the XMLDecoder class that accepts an InputSource object. Also, the createHandler method has been added, which returns a DefaultHandler object. This handler is used to parse XML archives created by the XMLEncoder class.

A new constructor has been added to the XMLEncoder class. This permits writing out JavaBeans to an OutputStream using a specific charset with a specific indention.

Saturday, April 21, 2012

Architecture: Modeling & Designing Software Projects Architecture

When I model and design the architecture of software project, first thing I consider is what is the software project type?

My experience in this field of projects architecture has taught me that most applications fails into seven software types, each type has its own technology's, communication patterns, architectural patterns and design steps.

The software categories are:

1. Object oriented Software:

The object-oriented design uses the concepts of information hiding, classes, and inheritance. This results in the design of a sequential object-oriented software architecture, which would be implemented as a sequential program with one thread of control.

2. Client / Server Software.

In these systems, a client is a requester of services and a server is a provider of services. Typical servers are file servers, database servers, and line printer servers. Client/server architectures are based on client/service architectural patterns, the simplest of which consists of one service and multiple clients. This pattern has several variations, which will be described next. In addition, certain decisions need to be considered about the design of client/server architectures, such as whether the server should be designed as a sequential or concurrent subsystem, what architectural structure patterns to use for the design of the client/server architecture, and what architectural communication patterns to use for interaction between the clients and the services.

Also differentiates between a server and a service. A server is a hardware/ software system that provides one or more services for multiple clients. A service in a client/server system is an application software component that fulfills the needs of multiple clients. Because services execute on servers, there is sometimes confusion between the two terms, and the two terms are sometimes used interchangeably. Sometimes, a server will support just one service or perhaps more than one; on the other hand, a large service might span more than one server node. In client/server systems, the service executes on a fixed server node(s) and the client has a fixed connection to the server.

3. Service-Oriented Architecture.

SOA is a distributed software architecture that consists of multiple autonomous services. The services are distributed such that they can execute on different nodes with different service providers. With a SOA, the goal is to develop software applications that are composed of distributed services, such that individual services can execute on different platforms and be implemented in different languages. Standard protocols are provided to allow services to communicate with each other and to exchange information. In order to allow applications to discover and communicate with services, each service has a service description; the service description defines the name of the service, the location of the service, and its data exchange requirements.

A service provider supports services used by multiple clients. Usually, a client will sign up for a service provided by a service provider, such as an Internet, email, or Voice over Internet Protocol (VoIP) service. Unlike client/server architectures, in which a client communicates with a specific service provided on a fixed server configuration, this chapter describes SOAs, which build on the concept of loosely coupled services that can be discovered and linked to by clients (also referred to as service consumers or service requesters) with the assistance of service brokers. This document describes how to design SOAs, how to design services, and how to reuse services.

4. Distributed Component-Based Software.

In the design of software architectures for a distributed component-based software design; the component-based software architecture for the distributed application is developed. The software application is structured into components, and the interfaces between the components are defined. To assist with this process, guidelines are provided for determining the components. Components are designed to be configurable so that each component instance can be deployed to a different node in a geographically distributed environment.

Components are initially designed using the subsystem structuring criteria. Additional component configuration criteria are used to ensure that components are indeed configurable – in other words, that they can be effectively deployed to distributed physical nodes in a distributed environment.

5. Concurrent Real-Time Software.

The real-time software is a concurrent architecture usually, having to deal with multiple streams of input events. They are typically state-dependent, with either centralized or decentralized control.

Real-time software architectures are concurrent architectures that usually have to deal with multiple streams of input events. They are typically state-dependent, with either centralized or decentralized control. Thus, the design of finite state machines, state-dependent interaction modeling, and the control patterns, are very important in the design of real-time software architectures.

6. Software Product Line.

It is architectures for families of products that need to capture both the commonality and variability in the family.

A software product line (SPL) consists of a family of software systems that have some common functionality and some variable. Software product line engineering involves developing the requirements, architecture, and component implementations for a family of systems, from which products (family members) are derived and configured.

The problems of developing individual software systems are scaled upwards when developing SPLs because of the increased complexity due to variability management.

As with single systems, a better understanding of a SPL can be obtained by considering the multiple views, such as requirements models, static models, and dynamic models of the product line. A graphical modeling language such as UML helps in developing, understanding, and communicating the different views. A key view in the multiple views of a SPL is the feature modeling view. The feature model is crucial for managing variability and product derivation because it describes the product line requirements in terms of commonality and variability, and defines the product line dependencies. Furthermore, it is desirable to have a development approach that promotes software evolution, such that original development and subsequent maintenance are both treated using feature-driven evolution.

7. Framework Software.

A software framework is an abstraction in which software providing generic functionality can be selectively changed by user code, thus providing application specific software. It is a collection of software libraries providing a defined application programming interface (API). It is a universal, reusable software platform used to develop applications, products and solutions.

Software Frameworks include support programs, compilers, code libraries, an application programming interface (API) and tool sets that bring together all the different components to enable development of a project or solution.

Frameworks contain key distinguishing features that separate them from normal libraries:

7.1. Inversion of control - In a framework, unlike in libraries or normal user applications, the overall program's flow of control is not dictated by the caller, but by the framework.

7.2. Default behavior - A framework has a default behavior. This default behavior must actually be some useful behavior and not a series of no-ops.

7.3. Extensibility - A framework can be extended by the user usually by selective overriding or specialized by user code providing specific functionality.

7.4. Non-modifiable framework code - The framework code, in general, is not allowed to be modified. Users can extend the framework, but not modify its code.

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Last thing is very important should be considered when architecting any project. It is Non-Functional requirements and should be taken into consideration when designing such software types from the modeling and design stage not when implementing the project.

In my architecture document I called it Software quality attributes.

Software quality attributes:

Refer to the nonfunctional requirements of software, which can have a profound effect on the quality of a software product. Many of these attributes can be addressed and evaluated at the time the software architecture is developed. Software quality attributes include maintainability, modifiability, testability, traceability, scalability, reusability, performance, availability, and security.

Some software quality attributes are also system quality attributes because they need both the hardware and software to achieve high quality. Examples of these quality attributes are performance, availability, and security. Other software quality attributes are purely software in nature because they rely entirely on the quality of the software. Examples of these quality attributes are maintainability, modifiability, testability, and traceability.

Wednesday, April 11, 2012

JPA: Dynamic search builder, the power of annotation, reflection and generics.

JPA (Java persistence API) is a powerful tool for domain objects mapping, and object oriented view perspective of database.

Always I used to use JPA in my projects, but JPA2 introduces extra feature that facilitate the generic way of persisting, merging, deleting and searching. Also introduces dynamic criteria API, which I was looking for.

But with time I have to change the dynamic query or do it myself or else to create new dynamic one which the panic way.

I need a component to search dynamically based on passed object attributes value, and not changed by the time.

For example if I have Bank that has (id, name, address, and state object), and I have created a bank object with name and address has values construct the JPQL SELECT statement (SELECT b FROM Bank b where b.name = :name AND b.address = :address) and search by it and so on.

I have developed a component to implement the above case called DynamicQueryBuilder with advanced techniques, and configurations.

In this article I will describe how I built this component with support of annotation, reflection and generics. In the code snippets you will find a brief description about each line of code and methods, the annotation developed to support the component and I will describe also the overall functionality of the component and how to call it to work dynamically…

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