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الأربعاء، 31 أغسطس 2011

Creating a Train Using an ADF Bounded Task Flow

You will use wizards to quickly create an application and projects, and a blank ADF bounded task flow for each train. The first train you will create consists of four pages (or train stops) that guide an end user to the completion of a task. The second train you will create consists of two pages in a multistep subtask. The second train will be called from

one of the train stops in the first train sequence.

Creating a Train Using an ADF Bounded Task Flow

To create a train sequence in a bounded task flow, you will use the task flow diagrammer and Component Palette to draw and connect train stops, call another train, change the train sequence, and add exit points. You will also add control flow rules to define how control flow passes from the called train back to the calling train when the called train flow exits. Next you will create a page template, add the ADF Train component, and bind the component to the train model. Then you will use the template to create JSF page fragments for the train stops. Finally, you will create a JSF page that consumes the first bounded task flow as an ADF region, then run the page.

Main page in browser

Purpose	Duration	Application
This tutorial shows you how to create bounded task flows with a train sequence that represents activities in a multistep page flow. To see the complete application you will create, click the Download button to download a zip of the final application, and then unzip it in your JDeveloper`mywork` folder.	40 minutes

Step 1: Create a New Application and Projects

From the main menu, choose File > New. In the New Gallery, expand the General category and select Applications. Then in the Items list, select Fusion Web Application (ADF) and click OK.

The JDeveloper application is the highest level in the organizational structure. While you are developing your application, it stores information about the objects you are working with.

To follow along with the example, enter TrainWebApp as the application name.

The application template you select determines the initial project structure, that is, the named project folders within the application workspace, and the application libraries that will be added.

Accept the defaults and click Finish.

The Application Overview window opens by default in the editor window area when you create a new application. You can optionally close the window, since you will not be using it to create objects for this application.

All objects that you create within JDeveloper appear in the Application Overview file summary pages, arranged by object type. You can create new files and artifacts, and view them filtered by status and project.

Step 2: Create a Task Flow for Each Train

In the Application Navigator, right-click the ViewController project and choose New > Web Tier > JSF/Facelets > ADF Task Flow, then click OK.

ADF task flows provide a modular approach for defining control flow in a Fusion web application. Instead of representing an application as a single large JSF page flow, you can break it up into a collection of reusable task flows.

In the Create ADF Task Flow dialog, enter or select the following values:

Field or Option Value

File Name train-flow.xml

Create as Bounded Task Flow selected

Create with Page Fragments selected

Create Train selected

Field or Option	Value
File Name	`train-flow.xml`
Create as Bounded Task Flow	selected
Create with Page Fragments	selected
Create Train	selected

A train represents a progression of related activities that guides an end user to the completion of a task.

Click OK.

By default JDeveloper displays the new bounded task flow in the diagrammer.

Only a bounded task flow that specifies the element in its metadata can be used to define a train task flow.

In the Component Palette, ADF Task Flow page, Components panel, drag and drop View on the diagrammer, then rename the activity. Do this four times, using the following activity names:

start
addresses
payment
review

The red error icons on the diagram indicate that the view activities are not yet associated with any physical page files.

Drag and drop Task Flow Return on the diagram. Accept the default name oftaskFlowReturn1.
In the Component Palette, click Control Flow Case. On the diagram, click the review icon, then click the taskFlowReturn1 icon. Rename the control flow case element to commit.

Like any bounded task flow diagram, you use a task flow return activity to indicate an exit point for the train flow and return control back to the caller.

In the Structure window, expand view - start. Right-click train-stop and choose Insert Inside train-stop > Display Name.
In the Property Inspector, enter Start in the Display Name field.
Repeat the procedure in steps 7 and 8 to add train stop display names to the remaining three view activities, using the following Display Name values:

Addresses
Payment
Review
In the Application Navigator, right-click the ViewController project and choose New > Web Tier > JSF/Facelets > ADF Task Flow, then click OK.
In the Create ADF Task Flow dialog, enter or select the following values, then click OK.

Field or Option Value

File Name childtrain-flow.xml

Create as Bounded Task Flow selected

Create with Page Fragments selected

Create Train selected

Field or Option	Value
File Name	`childtrain-flow.xml`
Create as Bounded Task Flow	selected
Create with Page Fragments	selected
Create Train	selected

The element is automatically added for you by JDeveloper when you check theCreate Train box in the Create Task Flow dialog.

In the Component Palette, drag and drop View on the diagrammer, then rename the activity tobilling. Repeat the procedure to add one more view activity, using the name shipping.
Drag and drop Task Flow Return on the diagram. Change the name to childFlowReturn1.
Draw a Control Flow Case from shipping to childFlowReturn1. Rename the case element todone.
In the Structure window, expand view - billing. Right-click train-stop and choose Insert Inside train-stop > Display Name. In the Property Inspector, enter Billing in the Display Name field.
Repeat the procedure in step 15 to add a display name to the remaining view activity, using theDisplay Name value Shipping.
Click Save All to save your work.

When you complete the steps for creating two bounded task flows as trains, the ViewControllerproject in the Application Navigator should look something like this,

Step 3: Add a Task Flow Call to a Train

In the editor window, click the train-flow.xml document tab to bring the diagram forward. (If not already open, double-click train-flow.xml in the Application Navigator to open the diagram.)
In the Application Navigator, under Page Flows in the ViewController project, drag childtrain-flowto the diagram and then drop it beneath the addresses icon.

A bounded task flow containing a train can use a task flow call activity to invoke a child bounded task flow representing another train.

On the diagram, right-click the review icon and choose Train > Move Backward.

A task flow call activity acts like a train stop, executing the default activity in the called task flow first. By default all train stops, including task flow calls acting as train stops, behave as sequential.

Then right-click the payment icon and choose Train > Move Backward.

The diagram should now look like this:
In the Component Palette, click Control Flow Case. On the diagram, click the childtrain-flowicon, then click the payment icon. Accept the default element name of childFlowReturn1.

When you call childtrain-flow in the parent train-flow, you have to manually wire a control flow case to return from the child train.

On the diagram, select the payment icon. In the Property Inspector, Train Stop section, enter falsein the Sequential field.

By default all train stops behave as sequential. In the Property Inspector, you can set theSequential option on the view activity for a train stop to specify whether it has sequential or nonsequential behavior.

In the Structure window, expand task-flow-call - childtrain-flow. Right-click train-stop and chooseInsert Inside train-stop > Display Name.
In the Property Inspector, enter Child train in the Display Name field.
Click Save All to save your work.

In the Structure window of train-flow.xml, the task-flow-call - childtrain-flow element should look like this when all its nodes are expanded:

Step 4: Create an ADF Page Template

In the Application Navigator, right-click the ViewController project and choose New > Web Tier > JSF/Facelets > ADF Page Template, then click OK.

If following along with the example, at this point there are no page fragments in the Application Navigator.

In the Create ADF Page Template dialog, enter traintemplate.jsf in the File Name field.
Confirm that Facelets is selected as the document type, and Use a Quick Start Layout is not selected.
With the Facet Definitions tab in front, click to add a facet. Enter body in the Name field, then click OK.

A page template is a template definition file written in XML.

At the top of the editor window, click the document tab traintemplate.jsf to make sure the visual editor is in focus.
In the Component Palette, ADF Faces page, Layout panel, drag Decorative Box and drop it on the blank page in the visual editor.

When you drag the component to the visual editor, you should see a target rectangle with the namePage Template Def on the page; this means the component you are dragging will be inserted inside that target.
In the Component Palette, Layout panel, Core Structure section, drag Facet and drop it into thecenter facet of the decorative box you just added.
Choose body from the Facet Name dropdown list, then click OK.

The body facet, defined in the page template definition, allows page authors to add their own content when they create their pages or page fragments using the page template.
Click Save All to save your work.

The visual editor should look similar to this:

This is just an example; it is entirely up to you how you want to arrange your template page layout.

Step 5: Add and Bind a Train Component

In the editor window, click the traintemplate.jsf document tab to make sure the template page is in focus. If necessary, click the Design tab at the bottom to use the visual editor.
In the Component Palette, ADF Faces page, General Controls panel, Location section, drag Train and drop it into the top facet of the decorative box component.

When a task flow consists of a set of pages that end users must visit in a particular order, use the ADF Faces Train component to display a progression of the related activities that guides end users to the completion of the task.

In the Property Inspector of the train component, Common section, choose Expression Builder from the dropdown menu next to the Value field.

The ADF Faces Train component enables end users to navigate through the train stops in an order specified in the underlying train model.

Expand ADF Controller Objects | controllerContext | currentViewPort | taskFlowContext. Then select trainModel and click OK.
Click Save All to save your work.

The visual editor should look similar to this:

This is just an example; it is entirely up to you how you want to arrange your page layout, and where you want to place the Train component.

Step 6: Create the Page Fragments for the Views

In the editor window, click the train-flow.xml document tab to bring the diagram forward.

If following along with the example, at this point there are no page fragments in the Application Navigator.

On the diagram, double-click a view icon (for example, start) to open the Create ADF Page Fragment dialog.
Accept the default file name (for example, start.jsff) and make sure Facelets is the selected document type.
On the Page Layout page, select Page Template and then select traintemplate from the dropdown list.
Click Managed Bean and then select Do not Automatically Expose UI Components in a Managed Bean.

In the Create ADF Page Fragment dialog, you can optionally specify whether or not components on the page are exposed in a managed bean, to allow programmatic manipulation of the UI components.

Click OK.

JDeveloper displays the page fragment in the visual editor. The Train component from the page template should be visible on the page.
In the visual editor, add contents to the page by inserting ADF Faces components into the body facet. To follow along with the example, in the Component Palette, ADF Faces page, Layout panel,Interactive Containers and Headers section, drag Panel Header and drop it into the body facet on the page. Then insert an output text component into the panel header component.

After creating a page fragment based on the template, you can add contents specific to the page you are creating by inserting appropriate ADF Faces components into the body facet.

Repeat steps 1 through 7 for each remaining view icon on the train-flow diagram.

After creating all the pages from the train-flow diagram,

In the editor window, click the childtrain-flow.xml tab to bring the diagram forward.
Repeat steps 2 through 7 for both view icons on the childtrain-flow diagram to create the page fragments.
In the editor window, click the billing.jsff tab to bring the page forward.
In the Component Palette, ADF Faces page, General Controls panel, Location section, drag Train Button Bar and drop it into the menuBar facet of the panel header component on the page.

If following along with the example, you would have added the panel header component as described in step 7.
Accept the EL expression of #{controllerContext.currentViewPort.taskFlowContext.trainModel} and click OK.

The Train Button Bar component is bound to the same train model as the Train component on the template.

In the editor window, click the shipping.jsff tab to bring the page forward.
In the Component Palette, Layout panel, drag Panel Group Layout and drop it into the menuBarfacet of the panel header component.
In the Property Inspector, Common section, select horizontal from the Layout dropdown list.
In the Component Palette, General Controls panel, Location section, drag Train Button Bar and drop it into af:panelGroupLayout - horizontal in the Structure window.
Accept the EL expression of #{controllerContext.currentViewPort.taskFlowContext.trainModel} and click OK.
In the Component Palette, General Controls panel, drag Button and drop it intoaf:panelGroupLayout - horizontal in the Structure window.
In the Property Inspector of the button component, Common section, enter Return to parent flow in the Text field. Then select done from the Action dropdown list.

At runtime, after users navigate into the child train flow pages, they need a way to navigate back to a parent train page.

Click Save All to save your work.

The buttons on the shipping.jsff page, which includes a Train Button Bar component with itsBack and Next buttons, should look similar to this:

The af:panelGroupLayout component in the Structure window of shipping.jsff should look like this:

Step 7: Invoke a Train Task Flow from a Region

In the Application Navigator, ViewController project, double-click adfc-config under Page Flows to open the default page flow diagram.

By default JDeveloper creates an empty unbounded task flow (source file adfc-config.xml) when you create a Fusion web application using the Fusion Web Application template.

In the Component Palette, ADF Task Flow page, Components panel, click View then click on the diagram to add a page icon. Change the default page name to main.
On the diagram, double-click the page icon you just added to open the Create JSF Page dialog.
Select Facelets as the document type and accept the default file name of main.jsf.
On the Page Layout page, select Quick Start Layout, then click Browse.
In the Component Gallery, select the Two Column category on the left. Then on the right, select the fourth type and the fifth layout.

You should see Two Column Left, Header (Stretched) under Options on the right.

ADF Faces provides a number of components that you can use to define the overall layout of a page.

Select Apply Themes, then click OK.

The Create JSF Page dialog should now display the quick start layout selection you made:
Click Managed Bean and select Do Not Automatically Expose UI Components in a Managed Bean. Then click OK.

JDeveloper displays the page in the visual editor.

When you use a quick start layout option, JDeveloper adds the components necessary to display the layout.

If you wish, you may go directly to step 14 to insert the train flow as a region, then run the page. Otherwise you may continue with the optional layout steps 10 through 13.
In the Component Palette, ADF Faces page, Layout panel, Interactive Containers and Headerssection, drag Panel Accordion and drop it on the start facet in the visual editor. In the Property Inspector, Common section, change DiscloseMany to true.
In the Structure window, expand af:panelAccordion. Select the child af:showDetailItem.
In the Property Inspector, Common section, change the Text value to Browse.
In the Structure window, right-click af:panelAccordion and choose Insert Inside af:panelAccordion > Show Detail Item to add a second pane. In the Property Inspector, Common section, change theText value to Search.
From the Application Navigator, drag the train-flow node under Page Flows and drop it on the centerfacet in the visual editor. From the Create context menu, choose Region.

An ADF region is a UI component whose content is based on a bounded task flow. To use a task flow as an ADF region within a page, the task flow must be a bounded task flow that contains at least one view activity or one task flow call activity to the page where you want to render the ADF region.

In the editor window, click the adfc-config.xml tab to bring the diagram forward. Right-click the mainpage icon and choose Run.

If the Create Default Domain dialog displays, enter the default password, for example weblogic1, in the Password and Confirm Password fields, then click OK.

When the application is run and the page is first rendered at runtime, the region's content on the page is that of the first view activity on the train-flow diagram:

By default, JDeveloper automatically configures an integrated server named Integrated WebLogic Server that references a user-specific instance of Oracle WebLogic Server bundled with the IDE.

Click the second train stop Addresses to navigate to the next page in the train flow.

While difficult to notice in this simple example, note that navigation to the Addresses view occurs within a region on the page. The content of the region is updated using partial page rendering (PPR).

The current stop in the train is indicated by the bold stop icon and display name.

Click the Payment train stop to jump ahead to the third stop without entering the child train flow.

This is possible because you set the third stop as nonsequential.
On the Payment page, click Addresses again, then click the Child train stop to enter the child train flow.

You should see the first page of the child train flow. A child train flow has an icon representation of the parent train before and after the child train stops.
Use the Back and Next buttons or the train stops to navigate forward and backward within the child train flow.
On the Shipping page, click the button to return to the parent train flow.

When you exit the child train flow, you should be returned to the Payment page in the parent train.

Summary

In this tutorial you created a user interface for navigating end users through a multistep process. You learned how to:

Use JDeveloper wizards and dialogs to create applications, task flows, page templates, and starter pages
Define bounded task flows as trains and draw train flows
Invoke another train using a task flow call activity
Use task flow return activities to return control flow back to the caller
Use control flow rules to handle control flow when the called train flow completes execution
Bind an ADF Train component to a train model
Add an ADF Region to a page
Use Integrated WebLogic Server to run a Fusion web application
http://download.oracle.com/docs/cd/E18941_01/tutorials/jdtut_11r2_44/jdtut_11r2_44.html

السبت، 23 يوليو 2011

Validating User Input

Validation Options for ADF BC Applications

There are various options for handling validation in ADF BC applications:

•Business services. You should build in as much validation as you can when creating the business services in order to protect the integrity of the data in the database and to prevent malicious attacks. There are a multitude of opportunities to add validation at the business services level:

-Oracle ADF Business Components provides a number of predefined validation rule classes that enable you to add business logic without writing a single line of code, or you can also add programmatic validation.

-You can implement validation in the database; however, such validation cannot be exposed in the UI. For example, you cannot use database validation to expose a list of valid values in the UI.

•User interface. The ADF Faces input components that you use to build the pages of your application also have built-in validation capabilities. You use these prebuilt ADF Faces validators to ensure that when a user edits or enters data in a field and submits the form, the data is validated against the rules and conditions you have specified. However, UI validation should always have equivalent validation at the business services layer, so that the same validation is applied when the model is exposed in other ways.

Triggering Validation Execution

Each entity row tracks whether or not its data is valid. When a user modifies a persistent attribute of an existing entity row or creates a new entity row, the entity is marked as invalid, and any validation that you have implemented is evaluated again before the entity is again considered valid. In validation rules, you can specify when this validation is executed as follows:

•Validation Level: In an entity validation rule, you can specify whether validation should be performed at the entity-level (the default) or at the transaction level. If you specify that it should be performed at the transaction level, it will be carried out after all entity-level validation. For this reason you should use this option where you want to ensure that a specific piece of validation is performed at the end of the process.

•Conditional Execution: You can enter a Boolean condition using a Groovy expression to define conditional validation execution. When the condition evaluates to true, the rule is executed. You have the option to test your expression to see if it is valid.

•Triggering Attributes: By default a validator fires on an attribute whenever the entity as a whole is dirty. However, in an entity validation rule, you can choose to trigger validation only when certain attributes change (when one of the triggering attributes is dirty).

Validation always occurs before changes are posted to the database. If you must code validation that depends on seeing posted changes, override the beforeCommit() method in the object’s Java file.

Handling Validation Errors

When a validation rule throws exceptions, the exceptions are bundled and returned to the client, and any database changes pertaining to the transaction are rolled back.

The Failure Handling tab in the Validation page of the Validation Rule page of the entity object editor (or the attribute editor) is where you specify the error message that you want to display to the end user when the validation fails.

You use the Validation Failure Severity option buttons to specify whether the message is an Error message (default) or Informational Warning.

You can enter Groovy expressions to populate variables in error message text to make the message more meaningful. And you can store messages in a resource bundle or property file to make them translatable.

Specifying the Severity of an Error Message

If you define the message as an Error message, the end user is not able to navigate out of the current field or record and must revisit the field where the data has failed the validation test. If the message is classified as a Warning, the user can continue after the message has been acknowledged.

Using Groovy Variables in Error Messages

Using Groovy variables in error messages enables you to display dynamic labels and values in your messages. This also makes your messages more reusable when adding to a resource, as described in the next slide.

When you create the message, use any variable name, surrounded by curly braces. JDeveloper automatically adds the variable as a message token in the lower part of the Failure Handling page.

You must supply the values for the message tokens. You can use expressions such as source.hints.OrderDate.label to reference the value of the user-friendly display label of the OrderDate attribute of the source entity object being evaluated. To reference the value, simply use the name of the attribute.

At run time, the error message is displayed with the specified labels and values.

Storing Error Messages as Translatable Strings

Typically you store error messages in a resource bundle or other property file to facilitate translation and reuse of messages. A resource bundle contains key-value pairs for any messages and data strings in your application that you want to translate or reuse.

To use an existing message or create a new stored message, perform the following steps:

1. Click the Select Text Resource button to go to the Select Text Resource dialog box.

2. In the Select Text Resource dialog box:

-To use an existing message, select it and click Select

-To create a new message, enter the message in the Value field. This automatically populates the Key field, but you can change the key to a more meaningful name if desired. You also enter a description, which can assist the translator in knowing how the message is to be used.

-Click Save and Select to store and use the message

Defining Validation in the Business Services

When you incorporate validation into the ADF BC business model, the most logical place to implement such validation is in the entity objects. Encapsulating business logic in these shared reusable components provides the following benefits:

•Ensures that your business information is validated consistently in every page where end users are allowed to make changes

•Simplifies maintenance by centralizing validation

Using Prebuilt Declarative Validation Rules

The easiest way to create and manage validation rules is through the declarative validation framework. Oracle ADF is shipped with a number of built-in declarative validation rules that will satisfy many of your business needs. You implement these rules through the entity object editor and they are stored in the entity object’s XML file.

You can implement these rules either on the entity object itself, or on its attributes. The next few slides show how to use the built-in declarative validation rules.

Defining Declarative Validation

To include declarative validation on an entity object, perform the following steps:

1. Double-click the entity object in the Application Navigator to invoke the editor.

2. Invoke the Validation Rule editor:

-For entity validation, in the Entity Validation Rule section of the General tab, click Add Validation Rule.

-For attribute-level validation, select the Attributes page and double-click the attribute for which you would like to define a validation rule. In the Edit Attribute dialog box, click Validation in the list on the left of the page. In the Validation pane (with the attribute selected) click New. You can also define attribute.

3. In the Add Validation Rule dialog box, select the type of validation required from the Rule Type list and add details of the rule.

4. Define validation execution rules and failure handling procedures by clicking the relevant tabs and entering the preferences.

5. Click OK. The validation rule is displayed in the list of validation rules for the entity or attribute that owns it.