Red Hat Summit Red Hat SummitSupportKonsoleEntwicklerDemo startenKontakt

Dieser Inhalt ist in der von Ihnen ausgewählten Sprache nicht verfügbar.

8.3. Starting conversations with GET requests

JSF does not define any action listener triggered when a page is accessed via a non-Faces request (a HTTP GET request, for example). This can occur when a user bookmarks the page, or navigates to the page via an <h:outputLink>.
Sometimes we want a conversation to begin immediately the page is accessed. Since there is no JSF action method, we cannot annotate the action with @Begin.
Further problems arise when the page requires state to be fetched into a context variable. We have already seen two methods of solving this problem. If the state is held in a Seam component, we can fetch the state in a @Create method. If not, we can define a @Factory method for the context variable.
If neither option works for you, Seam lets you define a page action in the pages.xml file. 
<pages> 
  <page view-id="/messageList.jsp" action="#{messageManager.list}"/>
  ... 
</pages>
Copy to Clipboard Toggle word wrap
This action method is called at the beginning of the render response phase — that is, any time the page is about to be rendered. If a page action returns a non-null outcome, Seam will process any appropriate JSF and Seam navigation rules. This can result in a completely different page rendering.
If beginning a conversation is all you want to do before rendering the page, you can use a built-in action method: 
<pages> 
  <page view-id="/messageList.jsp" action="#{conversation.begin}"/> 
  ... 
</pages>
Copy to Clipboard Toggle word wrap
You can also call this built-in action from a JSF control, and that #{conversation.end} similarly ends conversations.
The <begin-conversation> element can be used as follows for further control over joining existing conversations, or beginning a nested conversation, a pageflow, or an atomic conversation. 
<pages> 
  <page view-id="/messageList.jsp"> 
    <begin-conversation nested="true" pageflow="AddItem"/> 
  <page> 
  ... 
</pages>
Copy to Clipboard Toggle word wrap
There is also an <end-conversation> element. 
<pages> 
  <page view-id="/home.jsp"> 
    <end-conversation/> 
  <page> 
  ...
</pages>
Copy to Clipboard Toggle word wrap
We now have five options to begin a conversation immediately the page is accessed:
  • Annotate the @Create method with @Begin
  • Annotate the @Factory method with @Begin
  • Annotate the Seam page action method with @Begin
  • Use <begin-conversation> in pages.xml.
  • Use #{conversation.begin} as the Seam page action method
Nach oben
Red Hat logoGithubredditYoutubeTwitter

Lernen

Testen, kaufen und verkaufen

Communitys

Über Red Hat Dokumentation

Wir helfen Red Hat Benutzern, mit unseren Produkten und Diensten innovativ zu sein und ihre Ziele zu erreichen – mit Inhalten, denen sie vertrauen können. Entdecken Sie unsere neuesten Updates.

Mehr Inklusion in Open Source

Red Hat hat sich verpflichtet, problematische Sprache in unserem Code, unserer Dokumentation und unseren Web-Eigenschaften zu ersetzen. Weitere Einzelheiten finden Sie in Red Hat Blog.

Über Red Hat

Wir liefern gehärtete Lösungen, die es Unternehmen leichter machen, plattform- und umgebungsübergreifend zu arbeiten, vom zentralen Rechenzentrum bis zum Netzwerkrand.

Theme

© 2025 Red Hat