Oracle ADF | Techartifact

August 2, 2014October 11, 2014

I’m an Oracle ACE!

I have been chosen for the Oracle ACE award.I had accepted it.Now, I am an Oracle ACE!

I’m proud and humbled to be part of this group of technical Oracle experts, and hope to live up to their standards.This great title comes with great responsibilities.Now i am more responsible for add more knowledge to the community.I will try my level best to achieve this. I am 485th person who got this title.

Its a great learning experience for me as well.

Please check my Oracle ACE profile

Keep looking for some interesting post in future.

Happy learning with Vinay Kumar in techartifact.

July 22, 2014July 22, 2014

Create centeric page using ADF Faces

Requirement- To create center page using ADF faces.
Implementation – Well you can also achieve using decorative box and panelStrechtLayout.I am going to show, how you can create centered page using af:panelGroupLayout and af:panelStretchLayout.

Use af:panelStretchLayout -center facet->PanelGroupLayout (Halign as center).You can give size in px or % in top and bottom facet of af:panelStretchLayout

ADF developers are not good in html and css.Atleast not me.Now we should dig in more what is halign and valign.You must have seen this property in panelgroupLayout as below

HALIGN -> sets the horizontal alignment of the cells.

VALIGN -> sets the vertical alignment of the cells.

Below picture will make more clear

Source of the page can be

<?xml version='1.0' encoding='UTF-8'?>
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1"
          xmlns:f="http://java.sun.com/jsf/core"
          xmlns:h="http://java.sun.com/jsf/html"
          xmlns:af="http://xmlns.oracle.com/adf/faces/rich">
  <jsp:directive.page contentType="text/html;charset=UTF-8"/>
  <f:view>
    <af:document id="d1">
      <af:form id="f1">
        <af:panelStretchLayout id="psl1" topHeight="33%" bottomHeight="22%"
                               startWidth="5%" endWidth="5%">
          <f:facet name="bottom"/>
          <f:facet name="center">
          
            <af:panelGroupLayout id="pgl1" layout="vertical" halign="center"
                                 valign="middle">
              <af:panelFormLayout id="pfl1" rows="6" maxColumns="1">
                <f:facet name="footer"/>
                <af:inputText label="Name" id="it1"/>
                <af:inputText label="Last Name" id="it4"/>
                <af:inputText label="Email" id="it5"/>
                <af:inputText label="Phone" id="it3"/>
                <af:inputText label="Blog" id="it2"/>
                <af:commandButton text="Submit" id="cb1"/>
              </af:panelFormLayout>
              
            </af:panelGroupLayout>
          </f:facet>
          <f:facet name="start"/>
          <f:facet name="end"/>
          <f:facet name="top">
            <af:panelGroupLayout id="pgl2"/>
          </f:facet>
        </af:panelStretchLayout>
      </af:form>
    </af:document>
  </f:view>
</jsp:root>

When you run the page ,you will something like this-

happy learning with Vinay in techartifact…

July 6, 2014July 6, 2014

Running Oracle ADF application on High availability (HA) architecture

Oracle ADF is used to build large enterprise application. And if you want to have your application to run on high availabilty then you should understand what is High Availability (HA) .

What is High Availability –
High availability refers to the ability of users to access a system without loss of service. Deploying a high availability system minimizes the time when the system is down, or unavailable and maximizes the time when it is running, or available. This section provides an overview of high availability from a problem-solution perspective. With HA , even for new deployment you will never have down time.

Normally in large enterprise application , you don’t want your system to be down..Application deployed in cluster environment. If one of the server down then the user session should replicate to another cluster . Now , we have Oracle HTTP Server (OHS) or Apache plugin is to used to get single URL and manage internally to replicate the session and send request if one of cluster is fail.

How a web server handle request

Cluster- Group of managed server running to provide scalability and reliability. In this multiple wls instance simultaneously and working together.Cluster is part of WLS domain . A domain can have multiple cluster

Architecture of Weblogic HA

Now the important point for developer – Few points designing and developing Oracle ADF application for HA.
There are 6 types of memory scopes. Read more on ADF memory scopes

When the Fusion web application runs in a clustered environment, a portion of the application’s state is serialized and copied to another server or a data store at the end of each request so that the state is available to other servers in the cluster.If it not serialized then user will lose data upon fail-over.

WebLogic duplicates those sessions by serializing the objects in the session and than transfers it to the secondary machine. Only the object that are stored in the session will be replicated. From an ADF perspective this means that managed bean with pageFlowScope and above will be replicated.It is very well defined in Oracle documentation and A-team article.

Configuring Oracle ADF development for High Availability

=> Changes in Application server-

While doing development Jdeveloper integrated server will not throw any errors by default. Add this parameter in server has to be run with the following JVM parameter:

-Dorg.apache.myfaces.trinidad.CHECK_STATE_SERIALIZATION=all

Note that this check is disabled by default to reduce runtime overhead. Do not use this after your testing is complete.

-> Changes in ADF code

-> Please make sure that managed beans used in ADF application with a scope greater than one request should be serializable ( implement the java.io.Serializable interface). Specifically, beans stored in session scope, page flow scope, and view scope need to be serializable.

– All pageflowscope and viewscope managed beans should not contain UI bindings. In essence, component bindings should live for a http request (request scope or backingBean scope). Any state or data you need for a longer duration can be saved in a pageflowscope bean separately.

– Make sure Oracle ADF is aware of changes to managed beans stored in ADF scopes (view scope and page flow scope) and enable the tracking of changes to ADF memory scopes.

use below code to notify ADF

controllerContext ctx = ControllerContext.getInstance();
ctx.markScopeDirty(viewScope);

-> Configuring Application Modules

– Right-click the application module and select Configurations.Click Edit.Click the Pooling and Scalability tab.
Select the Failover Transaction State Upon Managed Release checkbox.

<AppModuleConfig ...
 <AM-Pooling jbo.dofailover="true"/>
</AppModuleConfig>

-> Configuring weblogic.xml

In weblogic.xml file, add entry as below persistent-store-type definition to the session-descriptor element like below

<weblogic-web-app>
    <session-descriptor>
    <persistent-store-type>
    replicated_if_clustered
    </persistent-store-type>
    </session-descriptor>
</weblogic-web-app>

-> Configuring adf-config.xml

In adf-config.xml file, add entry as like below

<adf-controller-config xmlns="http://xmlns.oracle.com/adf/controller/config">
 <adf-scope-ha-support>true</adf-scope-ha-support>
</adf-controller-config>

Happy Learning with Vinay In techartifact.

Ref- http://docs.oracle.com/cd/E12839_01/core.1111/e10106/adf.htm