Apache DeltaSpike

JSF Module

Overview

The JSF module provides CDI integration with JSF, with type-safe view config, multi-window handling, new scopes (WindowScoped, ViewScope, ViewAccessScoped, GroupedConversationScoped) and integration with DeltaSpike “core” messages and exception handling.

Project Setup

The configuration information provided here is for Maven-based projects and it assumes that you have already declared the DeltaSpike version and DeltaSpike Core module for your projects, as detailed in Configure DeltaSpike in Your Projects. For Maven-independent projects, see Configure DeltaSpike in Maven-independent Projects.

Declare JSF Module Dependencies

Add the JSF module to the list of dependencies in the project pom.xml file using this code snippet:

<dependency>
    <groupId>org.apache.deltaspike.modules</groupId>
    <artifactId>deltaspike-jsf-module-api</artifactId>
    <version>${deltaspike.version}</version>
    <scope>compile</scope>
</dependency>

<dependency>
    <groupId>org.apache.deltaspike.modules</groupId>
    <artifactId>deltaspike-jsf-module-impl</artifactId>
    <version>${deltaspike.version}</version>
    <scope>runtime</scope>
</dependency>

Or if you’re using Gradle, add these dependencies to your build.gradle:

     runtime 'org.apache.deltaspike.modules:deltaspike-jsf-module-impl'
     compile 'org.apache.deltaspike.modules:deltaspike-jsf-module-api'

Some EE6 servers cannot handle optional classes. From DeltaSpike 1.0.1, if you do not like the corresponding log entries during startup or the deployment fails, you can use an alternative impl-module (instead of deltaspike-jsf-module-impl):

<dependency>
    <groupId>org.apache.deltaspike.modules</groupId>
    <artifactId>deltaspike-jsf-module-impl-ee6</artifactId>
    <version>${deltaspike.version}</version>
    <scope>runtime</scope>
</dependency>

Or if you’re using Gradle, add these dependencies to your build.gradle:

     runtime 'org.apache.deltaspike.modules:deltaspike-jsf-module-impl-ee6'
Support of EAR deployments
Before using features described by this page, please ensure that you are aware of DELTASPIKE-335 and the corresponding impact.

JSF Messages

DeltaSpike provides an injectable component for typesafe FacesMessages.

Is provides an integration with MessageBundle making the use of JSF messages and I18N simple and type-safe.

Usage:

@MessageBundle
public interface Messages
{
    @MessageTemplate("Welcome to DeltaSpike")
    String welcomeToDeltaSpike();
}

 @Model
 public class MyJSFBean
 {
    @Inject
    private JsfMessage<Messages> messages;

    ...
    messages.addInfo().welcomeToDeltaSpike();
}

MessageBundle methods which are used as JsfMessage can return a org.apache.deltaspike.core.api.message.Message or a String. In case of a String we use it for both the summary and detail information on the FacesMessage.

If a Message is returned, we lookup the 'detail' and 'summary' categories (see org.apache.deltaspike.core.api.message.Message#toString(String) for creating the FacesMessage.

Multi-Window Handling

Background

Historic Considerations

Until the end of the 1990s web browsers are usually single threaded and only had one window. But in the last years browsers supporting multiple windows or even tab became the standard. Since those days lots of efforts went into uniquely identifying a single browser window on the server side. Sadly browser windows still lack of a native windowId, thus maintaining web application data in @SessionScoped backing beans is still used in most of the cases.

How JSF-2 Changed the World

The MyFaces Orchestra community did a good summary about the various ways to handle multiple window support in JSF Applications. Those findings are still valid and up to date, but the environmental conditions have changed slightly since then. It is easy to pass a windowId around with a POST request, but it gets tricky with GET requests. Due to the new JSF-2 ability to use bookmarkable URLs and deep links, a typical JSF-2 application contains much more GET links than we used to see in JSF-1, thus we have far more href links to cope with.

Standard windowId Handling

With a classical approach we would not be able to simply add a windowId parameter to such links because if the user would open the link in a new browser window or tab, we would carry the windowId - and thus the window scope - over to the new browser tab/window. The classic solution was to omit the windowId for all GET links, but by doing this we would now loose the window scope far too often with JSF-2! Marios summary also contains a method to prevent this problem by storing a value directly in the browser window via JavaScript. Usually this is rendered and executed in the same page as the user form. See the "Post-render window detection" paragraph for a more detailed description. The major downside of this solution is that we might already pollute 'foreign' beans (and destroy their information) while rendering the page, which means this is not feasible as general solution.

Available Modes

CLIENTWINDOW

Each GET request results in an intermediate small HTML page (aka "windowhandler"). If the window.name is empty, a new windowId will stored into window.name. If the window.name is already set, the windowhandler checks if the window.name equals the requested windowId. When the windowId is valid, a unique token (called dsrid) will be generated for the current request and added to the URL. In addition a cookie with with the dsrid/dswid will be added. On the server side, the verified windowId will be extracted from the cookie. For POST request detection, the windowId will be added as hidden input to all forms.

Advantage

  • Covers all edge cases

Disadvantage

  • Having the windowhandler.html site rendered between requests sometimes leads to some 'flickering' if the destination page takes some time to load. The browser first renders our windowhandler and only after that the original page will get loaded. This effect may be minimized by branding the windowhandler.html page and providing an own one with a bgcolor which matches your application. For html-5 aware browsers we also got rid of this flickering by storing away a 'screenshot' of the first page in onclick() and immediately restore this 'screenshot' on the intermediate windowhandler.html page. Technically we do this by storing away the HTML DOM tree and css information into the html5 localStorage and restore them on the intermediate page. We also introduced a WindowConfig which is able to parse a request and decide upon the UserAgent or any other information if a client will get an intermediate page or if he gets the result page directly.

Configuration
Reduce windowhandler.html flickering

Per default we only overwrite the onclick events of all links on the current page to make a 'screenshot' between requests. We also provide a mechanism to store the 'screenshot' on every button onclick:

@Specializes
public class MyClientWindowConfig extends DefaultClientWindowConfig
{
    @Override
    public boolean isClientWindowStoreWindowTreeEnabledOnButtonClick()
    {
        return true;
    }
}
Change windowhandler.html

To customize the look and feel of the windowhandler.html, you can simply provide a own via:

@Specializes
public class MyClientWindowConfig extends DefaultClientWindowConfig
{
    @Override
    public String getClientWindowHtml()
    {
        return "<html><body>Loading...</body></html>";
    }
}

If you didn’t copy the JS logic from our default windowhandler.html or if you would like to always show your custom html instead the 'screenshot', you should disable logic via:

@Specializes
public class MyClientWindowConfig extends DefaultClientWindowConfig
{
    @Override
    public boolean isClientWindowStoreWindowTreeEnabledOnLinkClick()
    {
        return false;
    }

    @Override
    public boolean isClientWindowStoreWindowTreeEnabledOnButtonClick()
    {
        return false;
    }
}
Minimize windowhandler.html streaming

It’s possible to reduce the windowhandler.html streaming if we overwrite the onclick event of all links to mark the next request as 'valid'. The onclick handler appends a request token to the URL and creates a cookie for the request token.

You can enable this via:

@Specializes
public class MyClientWindowConfig extends DefaultClientWindowConfig
{
    @Override
    public String isClientWindowTokenizedRedirectEnabled()
    {
        return true;
    }
}

LAZY

Always appends the windowId to all, from JSF generated, URLs. On the first GET request without a windowId, it will generate a new windowId and redirect, with the windowId in the URL, to the same view again. The current windowId will be stored in the window.name variable on the client side. For all further requests, a lazy check will be performed to check if the windowId in the URL is matching with the window.name. If it is not matching, the view will be refreshed with the right windowId in the URL.

Advantage

  • No windowhandler.html / loading screen required

Disadvantage

  • It could happen that 2 tabs will share the same windowId for 1 request because the LAZY mode will check lazily, after rendering the view, if the windowId matches the window.name. Therefore it could happen that scopes, which are based on the window handling (@ViewAccessScoped, @WindowScoped and @GroupedConversationScoped), will unintentionally be destroyed.

Workflow Example

First GET request with windowId

  • Renders the view

  • Stores the windowId as window.name on the client side

First GET request without windowId

  • Redirect to the same view with a new windowId in the URL

  • Renders the view

  • Stores the windowId as window.name on the client side

Further GET request with windowId

  • Renders the view

  • Checks if the requested windowId matches the window.name

  • If it does not match, reload the URL with the right windowId taken from window.name

Further GET request without windowId

  • Redirect to the same view with a new windowId in the URL

  • Renders the view

  • If it does not match, reload the URL with the right windowId taken from window.name

NONE

Any window or browser tab detection will be disabled for the current request. Scopes like @WindowScoped, @GroupedConversationScoped or @ViewAccessScoped will not work. This is also the default mode if the current request does not support Javascript or if the user agent is a bot/crawler.

DELEGATED

Delegates the complete window handling to the new JSF 2.2 ClientWindow (if not disabled).

CUSTOM

Enables to use an complete own org.apache.deltaspike.jsf.spi.scope.window.ClientWindow implementation.

Configuration

ds:windowId

The component ds:windowId (xmlns:ds="http://deltaspike.apache.org/jsf") is required to enable the full control of the DeltaSpike window handling. It will import and render the required script parts for both LAZY and CLIENTWINDOW mode. The best way, to apply it for all views, is to add this component to all of your templates.

ds:disableClientWindow

Similiar to JSF 2.2' disableClientWindow attribute, ds:disableClientWindow provides the ability to disable the rendering of the windowId to all links of all child components:

<ds:disableClientWindow>
    <h:link value="Link without windowId" outcome="target.xhtml" />
</ds:disableClientWindow>
<h:link value="Link with windowId" outcome="target.xhtml"/>

Number of Active Windows

By default, DeltaSpike allows 1024 active windows per session. Anyway, this number is reduced inside this JSF module to 64 for JSF applications. Once that the limit number of active windows is reached, DeltaSpike will drop the oldest active window.

You can change the default value by setting the property deltaspike.scope.window.max-count using DeltaSpike configuration mechanism.

You can also provide this value via:

@Specializes
public class MyClientWindowConfig extends DefaultClientWindowConfig
{

    @Override
    public int getMaxWindowContextCount()
    {
        // return the max active windows per session
    }
}

Switch Mode

To switch the mode, just provide a org.apache.deltaspike.jsf.api.config.JsfModuleConfig and overwrite #getDefaultWindowMode:

@Specializes
public class MyJsfModuleConfig extends JsfModuleConfig
{
    @Override
    public ClientWindowConfig.ClientWindowRenderMode getDefaultWindowMode()
    {
        //...
    }
}

Provide a Custom ClientWindow

If you would like to provide an custom org.apache.deltaspike.jsf.spi.scope.window.ClientWindow implementation, you can just do it, for example, via CDI alternatives:

@ApplicationScoped
public class MyClientWindow implements ClientWindow
{
    //...
}

Do not forget to set the ClientWindowRenderMode to 'CUSTOM' via the JsfModuleConfig:

@Specializes
public class MyJsfModuleConfig extends JsfModuleConfig
{
    @Override
    public ClientWindowConfig.ClientWindowRenderMode getDefaultWindowMode()
    {
        return ClientWindowConfig.ClientWindowRenderMode.CUSTOM;
    }
}

Based Scopes

  • @WindowScoped

  • @ViewAccessScoped

  • @GroupedConversationScoped

Scopes

@WindowScoped

The window-scope is like a session per window. That means that the data is bound to a window/tab and it not shared between windows (like the session scope does). Usually you need the window-scope instead of the session-scope. There areis not a lot of use-cases which need shared data between windows.

@WindowScoped
public class PreferencesBean implements Serializable
{
    //...
}

@ViewAccessScoped

In case of conversations you have to un-scope beans manually (or they will be terminated automatically after a timeout). However, sometimes you need beans with a lifetime which is as long as needed and as short as possible - which are terminated automatically (as soon as possible). In such an use-case you can use this scope. The simple rule is, as long as the bean is referenced by a page - the bean will be available for the next page (if it is used again the bean will be forwarded again). It is important that it is based on the view-id of a page (it is not based on the request) so, for example, Ajax requests do not trigger a cleanup if the request does not access all view-access scoped beans of the page. That’s also the reason for the name @ViewAccessScoped.

@ViewAccessScoped
public class WizardBean implements Serializable
{
    //...
}
@ViewAccessScoped beans are best used in conjunction with the CLIENTWINDOW window handling, which ensures a clean browser-tab separation without touching the old windowId. Otherwise a 'open in new tab' on a page with a @ViewAccessScoped bean might cause the termination (and re-initialization) of that bean.

@GroupedConversationScoped

See (Grouped-)Conversations

@ViewScoped

DeltaSpike provides an CDI context for the JSF 2.0/2.1 @javax.faces.bean.ViewScoped. You can simply annotate your bean with @javax.faces.bean.ViewScoped and @Named.

JSF 2.0 Scopes

JSF 2.0 introduced new annotations as well as a new scope - the View Scope. DeltaSpike allows to use all the CDI mechanisms in beans annotated with:

  • javax.faces.bean.ApplicationScoped

  • javax.faces.bean.SessionScoped

  • javax.faces.bean.RequestScoped

  • javax.faces.bean.ViewScoped

Furthermore, the managed-bean annotation (javax.faces.bean.ManagedBean) is mapped to @Named from CDI.

All these annotations are mapped automatically. So you will not face issues, if you import a JSF 2 annotation instead of the corresponding CDI annotation.

Integration with DeltaSpike Type-safe Messages

You can use DeltaSpike type-safe messages with JSF to provide i18n messages and test to an JSF appplicaton.

JSF module is also capable to use messages provided through in faces-config.xml file. The element allows you to override JSF default messages (Section 2.5.2.4 of the JSF specification contains the list of all JSF default messages that could be override.).

DeltaSpike can also reuse the same file to provide type-safe messages so you do not have to use the naming convention nor @MessageContextConfig. If there is a config for supported locales it will be checked as well and fallback to the configured default locale.

Example
@MessageBundle
public interface SimpleMessage
{
    @MessageTemplate("{welcome_to_deltaspike}")
    String welcomeToDeltaSpike();
}

@Model
public class PageBean
{

    @Inject
    private SimpleMessage messages;

    public void actionMethod(){
        FacesContext.getCurrentInstance().addMessage(null,new FacesMessage(messages.welcomeToDeltaSpike()));
    }

}


org.apache.deltaspike.example.message.SimpleMessage

->

org/apache/deltaspike/example/message/SimpleMessage.properties
org/apache/deltaspike/example/message/SimpleMessage.properties
org/apache/deltaspike/example/message/SimpleMessage_en.properties
org/apache/deltaspike/example/message/SimpleMessage_de.properties

...

//content (as usual in message bundle files):
welcome_to_deltaspike=Welcome to DeltaSpike
//Overrided JSF messages
javax.faces.component.UIInput.REQUIRED = {0}: Please enter a value
Faces-config.xml File
<faces-config>
    <application>
        <message-bundle>org.apache.deltaspike.example.message.SimpleMessage</message-bundle>
    </application>
</faces-config>

Type-safe View-Configs

Intro

Type-safe view-configs are static configs which can be used in combination with every view-technology which is based on Java. Currently DeltaSpike itself provides an integration for JSF, however, the basic concepts are independent of it. (Since DeltaSpike provides the default integration only for JSF, the whole documentation for view-configs is located here.)

Thanks to features like multiple (meta-data-)inheritance via interfaces, it provides a powerful approach to bind meta-data to one or multiple views. In case of the JSF integration it is possible to provide, for example, type-safe meta-data for security, navigation, callbacks for view-controllers. Beyond configuring view (/pages) via this concept, it is also possible to use the (view-)config classes for type-safe navigation. Since it is standard Java, you can benefit from any Java-IDE and you do not need special IDE-Addons to use it efficiently.

Even the concepts provided by modules (of DeltaSpike itself) are based on the basic API provided by the Core. So it is possible to introduce custom concepts the same way DeltaSpike itself does.

Motivation

Instead of learning the concepts and rules of view-configs provided by DeltaSpike, it might be easier for simple demos to just type some simple(r) strings. So why should you use something which is slightly more work initially?

The short answer is: It gives a good return in case of real applications (especially beyond simple demos).

The long answer is: You can benefit from it from the first second:

  • It is type-safe

    • the Java compiler ensures that you do not have typos at the final usages (and the rest can be checked during bootstrapping of the application)

    • you can benefit from the auto.complete features of any modern Java IDE.

  • If you change the name of a file/folder, you need only one (easy) code-change in a single place and your (standard Java-) IDE will do the rest for you (= update all usages) without a special plug-in

  • It is possible to restrict the navigation target → you can ensure that the navigation target is still the intended one (e.g. after a refactoring)

  • You can configure meta-data in a central place (which can get inherited via multiple inheritance based on Java interfaces)

  • Easier for developers to find usages

  • Allows easy(er) refactorings and maintenance

  • You can use your IDE more efficiently especially in large projects (there are some users who initially switched to it, because their tools for displaying the config they had before open large config files very slowly…​)

  • Modern Java IDEs show inheritance of interfaces and classes in a nice way. Since the view-config is based on standard classes and interfaces, you can benefit from it easily.

Advantages which are planned for later (= currently not supported):

  • It is possible to check if the configured folders and files really exist during/after the bootstrapping phase of the application (currently it is not implemented, but it is possible to do it).

  • It is also easy(er) for tools (IDE plugins,…​) to validate it

  • It is possible to validate the config (if the corresponding path (view or folder) really exists (after v0.5 it is done out-of-the-box)

If you are still not convinced, you just have to try it. You will see how your daily workflow benefits from it pretty soon.

Bean-discovery-mode Annotated

CDI 1.1 introduced a concept called bean-discovery-mode. If you would like to use the mode annotated, please have a look at the tip at @ViewConfigRoot

Basic API Usages

While reading this section keep the following simple rules in mind: Meta-data gets inherited along the path of Java inheritance File-/Folder- paths are build based on nesting classes and interfaces Usually users do not need to be aware of all descriptors, SPIs,…​ which are described by this documentation.

There are a lot of possibilities to configure views and some of them are optional. The following examples show some of them in combination with features provided by the JSF- and Security-Module of DeltaSpike.

The following example shows the minimal syntax for providing a config for a view (/page).

public class MyPage implements ViewConfig
{
}

Since it is a class (and not an interface), it is automatically recognized as config for a page (and not a folder) and the default settings get applied during bootstrapping. In case of JSF you can use it for navigation, for example, via action-methods.

public Class<? extends ViewConfig> toNextPage()
{
    return MyPage.class;
}

This leads to a forward to /myPage.xhtml. Information like base-path, file- (and folder-)name/s, file-extension, navigation mode, view-params,…​ can be customized with the corresponding (meta-data-)annotations. One of those annotations provided by the JSF module (which is optional) is @View. That means the following example leads to the same as the first one.

@View //optional
public class MyPage implements ViewConfig
{
}

But it is also possible to reflect the folder structure via nesting of interfaces and classes. An example for it is:

public interface Pages
{
    class Index implements ViewConfig { }

    interface AdminArea extends ViewConfig
    {
        class Index implements Admin { }
    }
}

In case of the JSF integration it leads to the following view-ids: /pages/index.xhtml /pages/adminArea/index.xhtml

Like the optional @View for pages represented by the classes, it is possible to use the optional @Folder annotation for directories represented by the (nested) interfaces.

Furthermore, it is possible to inherit meta-data along with the normal inheritance.

In the following example Pages.Admin.Index, Pages.Admin.Home and Pages.Admin.Statistics.Home inherit the meta-data from Pages.Admin because they implement the interface whereas Pages.Admin.Statistics.Index does not. However, Pages.Admin.Home overrides View#navigation. During the bootstrapping process the meta-data gets merged and at runtime you only see the final result (which is cached).

public interface Pages
{
    @View(name = "home", extension = JSP)
    class Index implements ViewConfig { }

    @View(navigation = REDIRECT, viewParams = INCLUDE)
    interface Admin extends ViewConfig
    {
        interface Statistics
        {
            @View //optional
            class Index implements ViewConfig { }

            class Home implements Admin { }
        }

        class Index implements Admin { }

        @View(navigation = FORWARD)
        class Home implements Admin { }
    }
}

In this case Pages.Admin.Statistics is just an interface to reflect the folder structure. For sure it is also possible that it extends an existing view-config interface and other folders and/or pages inherit its meta-data (like Pages.Admin).

Furthermore, inheritance can be used to ensure navigation to the correct area in the application. In the following example the return type of the action-method (and therefore the compiler of Java) ensures that the navigation target of this method is within the admin-area.

public Class<? extends Pages.Admin> toNextPage()
{
    return Pages.Admin.Index.class;
}

File (@View) and Folder (@Folder) Paths

@View as well as @Folder are optional annotations. @Folder is only needed for using a different folder-name or for marking folder configs if they do not inherit from org.apache.deltaspike.core.api.config.view.ViewConfig nor have a view-config for a page nested into them (like Pages.Wizard1.Step1). If it is not used explicitly, it gets added automatically (so you can query the meta-data at runtime even in cases you haveis not placed the annotations explicitly). @View allows to customize a bit more and it also gets added automatically if it is not used explicitly. Whereas @Folder gets added to all nested interfaces (above a view-config class - like Pages and Pages.Wizard1), @View only gets added to classes which in-/directly inherit from org.apache.deltaspike.core.api.config.view.ViewConfig (like Pages.Wizard1.Step1).

That means at runtime the following two configs lead to the same.

public interface Pages
{
    interface Wizard1
    {
        class Step1 implements ViewConfig { }
    }
}

//leads to the same as

@Folder
public interface Pages
{
    @Folder
    interface Wizard1
    {
        @View
        class Step1 implements ViewConfig { }
    }
}

The example above leads to the following paths:

  • /pages/

  • /pages/wizard1

  • /pages/wizard1/step1.xhtml

To customize it you can use @Folder#name, @View#basePath, @View#name and @View#extension (or you register custom `NameBuilder`s inline or globally).

@Folder#name

The rules are pretty simple. You will get what you write. There are only two additional features:

  • You do not have to care about duplicated '/' (e.g. /folder1//folder2/step1.xhtml would get corrected auto. to /folder1/folder2/step1.xhtml)

  • With "." at the beginning (e.g. "./") you can keep the path before.

The following example

interface Pages
{
    @Folder(name = "/w1/")
    interface Wizard1
    {
        class Step1 implements ViewConfig { }
    }

    @Folder(name = "./w2/")
    interface Wizard2 extends ViewConfig
    {
        class Step1 implements Wizard2 { }   //ViewConfig is inherited indirectly
    }
}

leads to the following paths:

  • /pages/

  • /w1/

  • /w1/step1.xhtml

  • /pages/w2/step1.xhtml

@View

The same naming rules apply to @View#basePath. However, it is only valid to be used at view-config nodes which represent pages (→ classes and not interfaces). On interfaces always use @Folder (@View#basePath will get ignored there).

interface Pages
{
    interface Wizard1
    {
        @View //optional
        class Step1 implements ViewConfig { }

        @View(basePath = "/")
        class Step2 implements ViewConfig { }

        @View(basePath = "./") //or just "."
        class Step3 implements ViewConfig { }

        @View(basePath = "/w1/")
        class Step4 implements ViewConfig { }

        @View(basePath = "./w1/")
        class Step5 implements ViewConfig { }
    }
}

leads to the following paths:

  • /pages

  • /pages/wizard1/

  • /pages/wizard1/step1.xhtml

  • /step2.xhtml

  • /pages/wizard1/step3.xhtml

  • /w1/step4.xhtml

  • /pages/wizard/w1/step5.xhtml

and depending on additional meta-data you would like to inherit (e.g. @View(navigation = REDIRECT)), you can also use:

@View(navigation = REDIRECT)
interface Pages extends ViewConfig
{
    interface Wizard1 extends Pages
    {
        @View
        class Step1 implements Wizard1 { }

        @View(basePath = "/")
        class Step2 implements Wizard1 { }

        @View(basePath = "./")
        class Step3 implements Wizard1 { }

        @View(basePath = "/w1/")
        class Step4 implements Wizard1 { }

        @View(basePath = "./w1/")
        class Step5 implements Wizard1 { }
    }
}

It leads to the same paths, but in addition @View#navigation gets inherited along the inheritance path.

Navigation Parameters

Since the view-config is static, an approach to add parameters is needed. The following part shows different possibilities to add parameters which end up in the final URL after '?' (in case of the integration with JSF). It is not needed to add all (types of) parameters that way. Some get added automatically based on special meta-data (e.g. @View#navigation and @View#viewParams). Instead of adding "faces-redirect=true" manually it is done for you as soon as you are using @View(navigation = REDIRECT). The same goes for "includeViewParams=true" and @View(viewParams = INCLUDE).

Static Configuration via @NavigationParameter

In some cases, it is needed to add an information in any case. So you can annotate the view-config class with @NavigationParameter. Supported values are static strings or EL-expressions.

public interface Pages extends ViewConfig
{
    @NavigationParameter(key = "param1", value = "staticValue1")
    class Index implements Pages { }

    @NavigationParameter.List({
        @NavigationParameter(key = "param1", value = "staticValue1"),
        @NavigationParameter(key = "param2", value = "#{myBean.property1}")
    })
    class Overview implements Pages { }
}

Instead of using parameters in any case, it is also possible to configure them statically for particular methods:

@Model
public class PageBean
{
    @NavigationParameter(key = "param2", value = "#{myBean.property1}")
    public Class<? extends ViewConfig> actionMethod1()
    {
        return SimplePageConfig.class;
    }

    @NavigationParameter.List({
        @NavigationParameter(key = "param1", value = "staticValue1"),
        @NavigationParameter(key = "param2", value = "staticValue2")
    })
    public Class<? extends ViewConfig> actionMethod2()
    {
        return SimplePageConfig.class;
    }
}
Dynamic Configuration via NavigationParameterContext

Instead of using parameters in a static fashion (as shown above), it is also possible to add them dynamically (e.g. in case of special conditions).

@Named
@SessionScoped
public class PageBean
{
    private int currentValue = -10;

    @Inject
    private NavigationParameterContext navigationParameterContext;

    public Class<? extends ViewConfig> actionMethod()
    {
        currentValue++;

        if (currentValue >= 0)
        {
            this.navigationParameterContext.addPageParameter("cv", this.currentValue);
        }
        return SimplePageConfig.class;
    }
}

Security Integration via @Secured

This annotation is a custom view-meta-data provided by the Security-module which allows to integrate third-party frameworks (or custom approaches) to secure pages as well as whole folders. You can annotate specific parts or a marker-interface. CustomAccessDecisionVoter used in the following example can be any implementation of org.apache.deltaspike.security.api.authorization.AccessDecisionVoter and needs to be a standard CDI bean which means you can use dependecy-injection to trigger any kind of security check. All parts which inherit from SecuredPages (Pages.Admin, Pages.Admin.Index and Pages.Admin.Home) are protected by CustomAccessDecisionVoter.

(It is easy to check this hierarchy in a modern Java-IDE. Only for displaying the final meta-data for every node in the IDE a special plug-in would be needed.)

@Secured(CustomAccessDecisionVoter.class)
public interface SecuredPages {}

@View(navigation = REDIRECT)
public interface Pages extends ViewConfig
{
    class Index implements Pages { }

    interface Admin extends Pages, SecuredPages
    {
        class Index implements Admin { }

        @View(navigation = FORWARD)
        class Home implements Admin { }
    }
}

For sure it is also possible to use it without a special interface. In this case you would need:

@View(navigation = REDIRECT)
public interface Pages extends ViewConfig
{
    class Index implements Pages { }

    @Secured(CustomAccessDecisionVoter.class)
    interface Admin extends Pages
    {
        class Index implements Admin { }

        @View(navigation = FORWARD)
        class Home implements Admin { }
    }
}

or:

@View(navigation = REDIRECT)
public interface Pages extends ViewConfig
{
    class Index implements Pages { }

    interface Admin extends Pages
    {
        @Secured(CustomAccessDecisionVoter.class)
        class Index implements Admin { }

        @Secured(CustomAccessDecisionVoter.class)
        @View(navigation = FORWARD)
        class Home implements Admin { }
    }
}

View-Controller Callbacks via @ViewControllerRef

This annotation is a custom view-meta-data provided by the JSF-module which allows to configure beans which should act as view-controllers. That means they can use view-controller callbacks like @InitView, @PreViewAction, @PreRenderView and @PostRenderView. The following example shows the usage of @PreRenderView.

//@View //optional
@ViewControllerRef(MyPageController.class)
public class MyPage implements ViewConfig
{
}

@Model
public class MyPageController
{
    @PreRenderView
    protected void load()
    {
        //...
    }
}

From DeltaSpike 0.7, it is possible to observe exceptions thrown by a @PreRenderView callback and use your configured Default-Error-View to display the exception.

Example
@ExceptionHandler
public class ErrorViewAwareExceptionHandler {
    @Inject
    private ViewConfigResolver viewConfigResolver;

    public void onIllegalStateException(@Handles ExceptionEvent<IllegalStateException> e)
    {
        FacesContext facesContext = FacesContext.getCurrentInstance();

        String viewId = viewConfigResolver.getDefaultErrorViewConfigDescriptor().getViewId();
        UIViewRoot viewRoot = facesContext.getApplication().getViewHandler().createView(facesContext, viewId);
        facesContext.setViewRoot(viewRoot);
        //... - e.g.: store the exception in a page-bean for the default-error-view
    }
}

Referencing Views via @ViewRef

With @ViewControllerRef#value you can annotate a view-config class to bind (/reference) a controller to it. @ViewRef#config allows the same in the other direction. Use an existing view-config to reference one or many view/s.

Example
public interface Pages extends ViewConfig
{
    class Index implements Pages { }
}

@ViewRef(Pages.Index.class)
//...
public class IndexController implements Serializable
{
    @PreRenderView
    protected void preRenderView()
    {
        //...
    }

    //...
}

The above example leads to the invocation of the pre-render-view logic before /pages/page1.xhtml gets rendered (and it will not be called for other pages).

Using the (Optional) ViewNavigationHandler

With JSF you typically navigate with the action-method bound to a command-component. However, also JSF supports manual navigation via javax.faces.application.NavigationHandler. With ViewNavigationHandler DeltaSpike provides an equivalent optimized for type-safe view-configs which is easier to use (and can be used also for other (supported) view technology).

Simple Example
public interface Pages {
    class Index implements ViewConfig { }
}

@Model
public class AnyController
{
    @Inject
    private ViewNavigationHandler viewNavigationHandler;

    public void anyMethod()
    {
        //navigates to /pages/index.xhtml
        this.viewNavigationHandler.navigateTo(Pages.Index.class);
    }
}

Also in this case (optional) meta-data will be used for the navigation process, since ViewNavigationHandler just delegates to the active navigation-handler (of JSF).

Configuring a Default Error-View

It is possible to mark one view-config class as default error-view. That means in case of errors it will be used as navigation target automatically. Furthermore, it is also possible to use it in your code instead of hardcoding your error-view across the whole application.

In case of

public interface Pages {
    class Index implements ViewConfig { }

    class CustomErrorPage extends DefaultErrorView { }
}

it is possible to navigate with DefaultErrorView.class instead of hardcoding it to Pages.CustomErrorPage.class.

@Model
public class PageController
{
    public Class<? extends ViewConfig> actionWithoutError()
    {
        return Pages.Index.class;
    }

    public Class<? extends ViewConfig> actionWithError()
    {
        //navigates to the view which is configured as default error-view
        return DefaultErrorView.class;
    }
}

If you are outside of an action-method you can also use it in combination with ViewNavigationHandler.

@Model
public class AnyController
{
    @Inject
    private ViewNavigationHandler viewNavigationHandler;

    public void anyMethod()
    {
        //navigates to the view which is configured as default error-view
        this.viewNavigationHandler.navigateTo(DefaultErrorView.class);
    }
}

However, in case of JSF you have to ensure that you are at a valid point in the JSF request-lifecycle for a navigation, because invocation gets transformed to a standard (implicit) JSF navigation.

Using ViewConfigResolver

If you would like to query view-meta-data yourself (for whatever reason), you can do that with ViewConfigResolver.

@RequestScoped
public class ApiDemoBean
{
    @Inject
    private ViewConfigResolver viewConfigResolver;

    public String getViewId(Class<? extends ViewConfig> viewConfigClass)
    {
        return viewConfigResolver.getViewConfigDescriptor(viewConfigClass).getViewId(); //or #getPath
    }

    public String getPath(Class pathConfigClass)
    {
        return viewConfigResolver.getConfigDescriptor(pathConfigClass).getPath();
    }

    public List<ConfigDescriptor<?>> getAllFolderDescriptors()
    {
        return viewConfigResolver.getConfigDescriptors();
    }

    public List<ViewConfigDescriptor> getAllPageDescriptors()
    {
        return viewConfigResolver.getViewConfigDescriptors();
    }

    public ViewConfigDescriptor getCurrentViewConfig()
    {
        return viewConfigResolver.getViewConfigDescriptor(FacesContext.getCurrentInstance().getViewRoot().getViewId());
    }

    public Class<? extends ViewConfig> getCurrentViewConfigClass()
    {
        return viewConfigResolver.getViewConfigDescriptor(FacesContext.getCurrentInstance().getViewRoot().getViewId()).getConfigClass();
    }
    //...
}

For folders it is optional to implement the ViewConfig interface, therefore you see 2 different types of API. #getConfigDescriptor as the general API and #getViewConfigDescriptor which is specific for pages (which have to implement the ViewConfig interface).

Besides translating a config class to the final path of the folder or page, it is possible to get the implicitly as well as explicitly configured (view-)meta-data and get and/or execute configured callbacks.

Advanced API Usages

Creating Custom Meta-Data via @ViewMetaData

This meta-annotation allows to create custom view-meta-data which can be used for view-configs. By default meta-data of a lower level overrides meta-data on a higher level which has the same type. That can be customized via annotating the final annotation as a whole via @Aggregated(true).

@ViewMetaData
@interface InfoPage
{
}

By just using @InfoPage in view-configs, it can be queried via:

@Inject
private ViewConfigResolver viewConfigResolver;
//...

ViewConfigDescriptor viewConfigDescriptor = viewConfigResolver.getViewConfigDescriptor(Pages.Index.class);
List<InfoPage> metaDataList = viewConfigDescriptor.getMetaData(InfoPage.class)

Creating Custom Meta-Data via @Stereotype

Like with CDI itself you can encapsulate multiple view meta-data annotation in one annotation.

Example
@Target({TYPE})
@Retention(RUNTIME)

@Stereotype
@Secured(CustomAccessDecisionVoter.class) //view meta-data #1
@View(navigation = REDIRECT) //view meta-data #2
@interface MySecuredView {}

Instead of using the same combination of annotations in multiple places, you can use the stereotype annotation. If you query the meta-data at runtime (see ViewConfigDescriptor#getMetaData), you can access @Secured as well as @View (in the example above). however, you will not see @MySecuredView itself at runtime, because stereotype annotations are by default transparent.

From DeltaSpike 1.0.1, it is possible to access such stereotype annotations as well, once you annotate them with @ViewMetaData.

Creating Custom Callbacks via @ViewMetaData

Via a custom ConfigPreProcessor it is possible to register custom callbacks dynamically. The following listing shows a view-config which adds a simple callback including the corresponding ConfigPreProcessor and ExecutableCallbackDescriptor.

@ViewMetaData(preProcessor = MySecured.AnnotationPreProcessor.class)
public @interface MySecured
{
    Class<? extends TestAccessDecisionVoter>[] value();

    class AnnotationPreProcessor implements ConfigPreProcessor<MySecured>
    {
        @Override
        public MySecured beforeAddToConfig(MySecured metaData, ViewConfigNode viewConfigNode)
        {
            List<CallbackDescriptor> descriptors = viewConfigNode.getCallbackDescriptors(MySecured.class);
            descriptors.add(new Descriptor(metaData.value(), DefaultCallback.class));
            return metaData;
        }
    }

    static class Descriptor extends ExecutableCallbackDescriptor<Set<String>>
    {
        public Descriptor(Class[] beanClasses, Class<? extends Annotation> callbackMarker)
        {
            super(beanClasses, callbackMarker);
        }

        public List<Set<String>> execute(String param1, String param2)
        {
            return super.execute(param1, param2);
        }
    }
}

By just using @MySecured in view-configs, it can be queried and executed via:

@Inject
private ViewConfigResolver viewConfigResolver;
//...
ViewConfigDescriptor viewConfigDescriptor = viewConfigResolver.getViewConfigDescriptor(Pages.Secured.Index.class);

List<Set<String> /*return type of one callback*/> callbackResult =
    viewConfigDescriptor.getExecutableCallbackDescriptor(MySecured.class, MySecured.Descriptor.class)
        .execute("param1", "param2");

It is also possible do register different callback-types per view-meta-data. An example can be found at ViewControllerRef which registers different callback-types for InitView, PreViewAction, PreRenderView and PostRenderView. In this case it is needed to use the type of the callback (= class of the annotation) as additional parameter for #getExecutableCallbackDescriptor.

Creating Custom inline Meta-Data via @InlineViewMetaData

This annotation can be used for view-meta-data which can be placed on other classes than view-config-classes. It is used, for example, for @ViewRef. Via a TargetViewConfigProvider it is possible to point to the view-config the meta-data should get applied to and via InlineMetaDataTransformer it is possible to convert it to a different meta-data-representation (which allows that at runtime you only have to support one side since the inline-meta-data was converted to the same meta-data representation which is used for the normal view-meta-data).

Path-Validation

DeltaSpike (after v0.5) validates your configs out-of-the-box. The application will fail to start, if there is an invalid config (e.g. a view-config without a corresponding view). Right now the validation is restricted to folders and view-ids with .xhtml or .jsp as suffix. Other view-ids (e.g. *.faces) do not get checked. In such cases a custom validator can be used (e.g. based on ViewConfigPathValidator).

To disable the view-config (path) validation, add a ClassDeactivator which restricts org.apache.deltaspike.jsf.impl.config.view.ViewConfigPathValidator.

View-Config SPI

ConfigDescriptorValidator

Allows to validate the final view-config descriptors before they get deployed. Since the config-descriptor contains, for example, the final path, it is also possible to validate if the corresponding file exists. Use @ViewConfigRoot to configure 1-n validators.

ConfigNodeConverter

Allows to provide custom strategies to process the nodes of the built config-tree. Use @ViewConfigRoot to configure a custom converter.

ConfigPreProcessor

Allows to change the found meta-data (e.g. replace default values, callbacks,…​) or the ViewConfigNode itself.

InlineMetaDataTransformer

Allows to transform an annotation annotated with @InlineViewMetaData to an annotation annotated with @ViewMetaData. This transformer is optional and only needed if it should result in the same at runtime, but the inline-meta-data needs a different syntax via a different annotation (compared to the view-config meta-data). See for example @ViewRef vs. @ViewControllerRef.

TargetViewConfigProvider

Allows to provide a custom reference to ViewConfig classes (see for example @InlineViewMetaData and @ViewRef)

ViewConfigInheritanceStrategy

Allows to customize the inheritance-strategy for meta-data. For example, inheritance via standard java inheritance vs. inheritance via nested interfaces. Use @ViewConfigRoot to configure a custom inheritance-strategy.

ViewConfigNode

Node-type used for building the meta-data-tree during the bootstrapping process.

@ViewConfigRoot

Optional annotation which allows to provide custom implementations. Only annotate one ViewConfig class which represents the root node.

If you are using CDI 1.1+ with bean-discovery-mode annotated, you can use @ViewConfigRoot in combination with @ApplicationScoped as marker annotations. From DeltaSpike 1.0.1, this combination allows to add all nested interfaces and classes and therefore no additional annotations (required by bean-discovery-mode annotated) are needed. Minimal example:

@ApplicationScoped
@ViewConfigRoot
public interface Pages extends ViewConfig
{
    class Index implements Pages { }
}

Activation of Custom Naming Conventions

DeltaSpike allows to customize the default naming convention via View.DefaultBasePathBuilder and/or View.DefaultFileNameBuilder and/or View.DefaultExtensionBuilder. It is possible to change it for one usage via View.basePathBuilder and/or View.fileNameBuilder and/or View.extensionBuilder or globally via the config mechanism provided by DeltaSpike. The same is supported for folders via Folder.DefaultFolderNameBuilder. In this case changing only one usage is possible via Folder.folderNameBuilder.

(Grouped-)Conversations

DeltaSpike conversations are based on the window-scope. Therefore, do not forget to add the ds:windowId (xmlns:ds="http://deltaspike.apache.org/jsf") component in case of ClientWindowConfig#CLIENTWINDOW to your page(/template) and ensure that the window-handling works properly (otherwise conversations will not work correctly). The base principle is similar to CODI-Conversations. CODI users just have to ensure that they have to add ds:windowId and the names are slightly different.

First of all, it is important to mention that DeltaSpike starts (grouped) conversations automatically as soon as you access conversation scoped beans. Furthermore, the invocation of GroupedConversation#close leads to an immediate termination of the conversation.

@GroupedConversationScoped
public class DemoBean1 implements Serializable
{
    //...
}

  1. leads to a conversation which contains just one bean with the group DemoBean1.

If you would like to use the bean within your JSF pages, you have to add @Named (javax.inject.Named ).

(In case of CDI standard conversations there is just one big conversation which contains all conversation scoped beans.) The grouped conversations provided by DeltaSpike are completely different. By default every conversation scoped bean exists in an "isolated" conversation. That means there are several parallel conversations within the same window.

Separated DeltaSpike Conversations
@GroupedConversationScoped
public class DemoBean2 implements Serializable
{
    //...
}

@GroupedConversationScoped
public class DemoBean3 implements Serializable
{
    //...
}

The above example leads to two independent conversations in the same window (context). If you close the conversation of DemoBean2, the conversation of DemoBean3 is still active. If you have an use-case (e.g. a wizard) which uses multiple beans which are linked together very tightly, you can create a type-safe conversation group.

Grouped Conversation Scoped Beans
interface Wizard1 {}

@GroupedConversationScoped
@ConversationGroup(Wizard1.class)
public class DemoBean4 implements Serializable
{
    //...
}

@GroupedConversationScoped
@ConversationGroup(Wizard1.class)
public class DemoBean5 implements Serializable
{
    //...
}

You can use @ConversationGroup to tell DeltaSpike that there is a logical group of beans. Technically @ConversationGroup is just a CDI qualifier. Internally DeltaSpike uses this information to identify a conversation. In the previous example both beans exist in the same conversation (group). If you terminate the conversation group, both beans will be destroyed. If you do not use @ConversationGroup explicitly, DeltaSpike uses the class of the bean as conversation group.

Injecting a Conversation Scoped Bean with an Explicit Group
//...
public class CustomBean1
{
    @Inject
    @ConversationGroup(Group1.class)
    private CustomBean2 demoBean;

    @Inject
    @ConversationGroup(Group2.class)
    private CustomBean2 demoBean;
}

Since @ConversationGroup is a standard CDI qualifier you have to use it at the injection point. You have to do that especially because it is possible to create beans of the same type which exist in different groups (e.g. via producer methods).

Producer Methods which Produce Conversation Scoped Beans with

Different Groups

interface Group1 {}
interface Group2 {}

public class CustomBean2
{
    @Produces
    @GroupedConversationScoped
    @ConversationGroup(Group1.class)
    public CustomBean2 createInstanceForGroup1()
    {
        return new CustomBean2();
    }

    @Produces
    @GroupedConversationScoped
    @ConversationGroup(Group2.class)
    public CustomBean2 createInstanceForGroup2()
    {
        return new CustomBean2();
    }
}

Terminating Conversations

You can inject the conversation via @Inject and use it to terminate the conversation immediately or you inject the GroupedConversationManager which can be used to terminate a given conversation (group). All conversations within a window are closed automatically, once WindowContext#closeWindow gets called for the window.

Injecting and Using the Current Conversation
@GroupedConversationScoped
public class DemoBean6 implements Serializable
{
    @Inject
    private GroupedConversation conversation; //injects the conversation of DemoBean6 (!= conversation of DemoBean7)

    //...

    public void finish()
    {
        this.conversation.close();
    }
}

@GroupedConversationScoped
public class DemoBean7 implements Serializable
{
    @Inject
    private GroupedConversation conversation; //injects the conversation of DemoBean7 (!= conversation of DemoBean6)

    //...

    public void finish()
    {
        this.conversation.close();
    }
}
Injecting and Using the Explicitly Grouped Conversation
interface Wizard2 {}

@GroupedConversationScoped
@ConversationGroup(Wizard2.class)
public class DemoBean8 implements Serializable
{
    @Inject
    private GroupedConversation conversation; //injects the conversation of Wizard2 (contains DemoBean8 and DemoBean9)

    //...

    public void finish()
    {
        this.conversation.close();
    }
}

@GroupedConversationScoped
@ConversationGroup(Wizard2.class)
public class DemoBean9 implements Serializable
{
    @Inject
    private GroupedConversation conversation; //injects the conversation of Wizard2 (contains DemoBean8 and DemoBean9)

    //...

    public void finish()
    {
        this.conversation.close();
    }
}
Terminating a Grouped Conversation Outside of the Conversation
//...
public class DemoBean10 implements Serializable
{
    @Inject
    private GroupedConversationManager conversationManager;

    //...

    public void finish()
    {
        this.conversationManager.closeConversationGroup(Wizard2.class);  //closes the conversation of group Wizard2.class
    }
}
Terminate All Conversations
//...
public class DemoBean11 implements Serializable
{
    @Inject
    private GroupedConversationManager conversationManager;

    //...

    public void finish()
    {
        this.conversationManager.closeConversations();  //closes all existing conversations within the current window (context)
    }
}
DeltaSpike conversations get closed/restarted immediately instead of keeping them until the end of the request like standard conversations do, because the behaviour of standard conversations breaks a lot of use-cases. However, if you really need to keep them until the end of the request, you can close them in a @PostRenderView callback.

Sub-Conversation-Groups

Due to the parallel conversation concept of DeltaSpike there is no need of something like nested conversations. Just use them in parallel and terminate them in a fine-granular way as soon as you do not need them any longer. As described above, you can terminate a whole conversation-group. However, sometimes it is essential to have subgroups if you need to end just a part of an use-case instead of all beans related to an use-case. A sub-group is just a class or an interface used to identify a bunch of beans within a group. To terminate such a sub-group, it is just needed to pass the class/interface to the corresponding API for terminating a conversation. The sub-group gets detected automatically and instead of terminating a whole conversation-group, the beans of the sub-group get un-scoped.

Explicitly Listing Beans of a Sub-group
public class MyGroup{}

@GroupedConversationScoped
@ConversationGroup(MyGroup.class)
public class BeanA {}

@GroupedConversationScoped
@ConversationGroup(MyGroup.class)
public class BeanB {}

@GroupedConversationScoped
@ConversationGroup(MyGroup.class)
public class BeanC {}

@ConversationSubGroup(subGroup = {BeanA.class, BeanB.class})
public class MySubGroup extends MyGroup {}

//or

@ConversationSubGroup(of = MyGroup.class, subGroup = {BeanA.class, BeanB.class})
public class MySubGroup {}
Terminating a Sub-group
@Inject
private GroupedConversationManager conversationManager;

//...
this.conversationManager.closeConversationGroup(MySubGroup.class);

As you see the class/interface of the sub-group has to extend/implement the group or you specify it via the @ConversationSubGroup#of. With @ConversationSubGroup#subGroup you can list all beans which belong to the sub-group. If you have a lot of such beans or you would like to form (sub-)use-case oriented groups, you can use implicit groups:

Implicit Sub-group
public interface Wizard {}

@ConversationSubGroup(of = MyGroup.class, subGroup = Wizard.class)
public class ImplicitSubGroup
{
}

@Named("myWizard")
@GroupedConversationScoped
@ConversationGroup(MyGroup.class)
public class WizardController implements Serializable, Wizard
{
    //...
}

this.conversationManager.closeConversationGroup(ImplicitSubGroup.class);

In the listing above all beans which implement the Wizard interface will be closed as soon as you close the ImplicitSubGroup.

Injection in JSF Artifacts

Converter and Validator

Per default the JSF module of DeltaSpike handles JSF converters and validators as std. CDI beans and therefore it’s possible to use injection, lifecycle-callbacks, scope-annotations,…​ the same way as with any other CDI bean. The usage is the same as for PhaseListener s.

PhaseListener

Once a std. JSF-PhaseListener is annotated with @org.apache.deltaspike.jsf.api.listener.phase.JsfPhaseListener, that PhaseListener gets active without additional config in faces-config.xml. Since such PhaseListener s are std. CDI beans, it’s possible to use injection, lifecycle-callbacks as well as scope-annotations the same way as with any other CDI bean. Furthermore, it’s possible to order PhaseListener s via ordinal. DeltaSpike itself uses it internally e.g. in case of DoubleSubmitAwarePhaseListener which looks like:

Example
@JsfPhaseListener(ordinal = 9000)
public class DoubleSubmitAwarePhaseListener implements PhaseListener, Deactivatable
{
    @Inject
    private PostRequestTokenManager postRequestTokenManager;

    @Override
    public void beforePhase(PhaseEvent event)
    {
        //...
    }

    @Override
    public void afterPhase(PhaseEvent event)
    {
        //...
    }

    @Override
    public PhaseId getPhaseId()
    {
        return PhaseId.RESTORE_VIEW;
    }
}

Event broadcasting

Observe Faces-Requests

It is possible to observe JSF-Requests via @Observes in combination with @org.apache.deltaspike.core.api.lifecycle.Initialized or @org.apache.deltaspike.core.api.lifecycle.Destroyed as qualifier for javax.faces.context.FacesContext.

Such observer-methods look e.g. like:

Example
public void onBeforeFacesRequest(@Observes @Initialized FacesContext facesContext) {
    //...
}

public void onAfterFacesRequest(@Observes @Destroyed FacesContext facesContext) {
    //...
}

BeforePhase / AfterPhase

It is possible to observe JSF request-lifecycle phase-events via @Observes in combination with @org.apache.deltaspike.jsf.api.listener.phase.BeforePhase or @org.apache.deltaspike.jsf.api.listener.phase.AfterPhase as qualifier for javax.faces.event.PhaseEvent.

Such observer-methods look e.g. like:

Example
public void onPhaseStart(@Observes @BeforePhase(JsfPhaseId.ANY_PHASE) PhaseEvent event) {
    //...
}

public void onPhaseEnd(@Observes @AfterPhase(JsfPhaseId.ANY_PHASE) PhaseEvent event) {
    //...
}

JSF SystemEvents

Following JSF SystemEvents can be observed via CDI:

  • javax.faces.event.PostConstructApplicationEvent

  • javax.faces.event.PreDestroyApplicationEvent

  • javax.faces.event.ExceptionQueuedEvent

Example
@ApplicationScoped
public class ApplicationConfig
{
    public void init(@Observes PostConstructApplicationEvent event)
    {
        // ...
    }
}

Integration with Exception Control

Whenever a unhandled exception occurs within the JSF lifecycle, our JSF ExceptionHandler provides a integration to the DeltaSpike Exception Control.

Examples

Basic

@ExceptionHandler
public class ApplicationExceptionHandler
{
    public void handleELException(@Handles ExceptionEvent<ELException> event)
    {
        // ...

        // no other JSF ExceptionHandler should handle this exception...
        event.handled();
    }
}

Redirect

@ExceptionHandler
public class ApplicationExceptionHandler
{
    public void handleELException(@Handles ExceptionEvent<ELException> event)
    {
        FacesContext.getCurrentInstance().getApplication().getNavigationHandler().handleNavigation(...); // or ExternalContext etc.

        // required - "stops" the JSF lifecycle
        FacesContext.getCurrentInstance().responseComplete();

        // no other JSF ExceptionHandler should handle this exception...
        event.handled();
    }
}

Using a Custom Qualifier for JSF Exceptions

In some cases, it is required to differentiate exceptions from JSF and normal exceptions. This is possible via a CDI qualifier:

@Target({ ElementType.TYPE, ElementType.PARAMETER })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Qualifier
public @interface Jsf
{
}

@Specializes
public class MyJsfModuleConfig extends JsfModuleConfig
{
    public Class<? extends Annotation> getExceptionQualifier()
    {
        return Jsf.class;
    }
}

@ExceptionHandler
public class ApplicationExceptionHandler
{
    public void handleELException(@Handles @Jsf ExceptionEvent<ELException> event)
    {
        FacesContext.getCurrentInstance().getApplication().getNavigationHandler().handleNavigation(...); // or ExternalContext etc.

        // required - "stops" the JSF lifecycle
        FacesContext.getCurrentInstance().responseComplete();

        // no other JSF ExceptionHandler should handle this exception...
        event.handled();
    }
}

Double-Submit Prevention

To avoid that the same content of a form gets submitted and therefore processed multiple times, it is possible to use the tag <ds:preventDoubleSubmit/>. As usual for DeltaSpike JSF-tags, the ds namespace is http://deltaspike.apache.org/jsf. Just add this tag within every JSF form-tag, you would like to safeguard.

<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:ds="http://deltaspike.apache.org/jsf">
    <h:head>
        <!-- head content -->
    </h:head>
    <h:body>
        <h:form>
            <!-- form content -->
            <ds:preventDoubleSubmit/>
        </h:form>
    </h:body>
</html>

Tips

Using errorView, DefaultErrorView or ViewNavigationHandler will fail with Weld versions older than 1.1.10 due to WELD-1178.