1)OC4J is used for executing Servlets,Java Server Pages (JSP), Enterprise Java Beans (EJB)
2)OC4J replaces the older JServ implementation for running servlets on the web server
3)Oracle Application Server 10gR3 (10.1.3) is the latest production version
OC4J is based on J2EE standards:Specific directory structure,File requirements (content & naming conventions),XML file definitionOC4J instances run in JVM’s and communicate through mod_oc4j / Apache
R12 creates 3 OC4J instances:
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Oacore: runs OA Framework-based applications
Forms: runs Forms-base applications
OAFM: runs web services, mapviewer, ascontrol
Number of OC4J instances for each group will be determined by corresponding nprocs context variable ( s_oacore_nprocs, s_forms_nprocs/s_frmsrv_nprocs, s_oafm_nprocs).
Servlets deployed to OC4J server adhere to J2EE specification
Deployment is through an Enterprise Archive (EAR) file, which contains the application definition and Web Application (WAR) files, which in turn includes the web application code (JAR), and associated configuration files (servlet definitions), JSP code,HTML
Forms.EAR 10.1.2 is deployed to the OC4J container in Application Server 10.1.3AutoConfig is used for configuration management similar to Release 11i.
Important files used for configuation of OC4J instances
Oc4j.properties : defines basic Apps directory aliasing,dbc file location is defined in this fileServer.xml : defines J2EE applications and their shared libraries for runtime OC4J.
Orion-application.xml : defines location of Java classes of all J2EE web modules deployed under J2EE. applicationOrion-web.xml : defines servlet level parameters for J2EE web modules.
These files are synomynous with jserv.conf,jserv.properties in 11i.
Oracle Process Manager and Notification server (OPMN) manages AS components and consists of:
Oracle Notification Server (ONS):
Delivers notifications between components
OHS<->OPMN<->OC4J
Process Manager (PM) start,stop, restart, death detection
($ADMIN_SCRIPTS_HOME contains the Apps equivalent scripts called ad*)
Single configuration file(opmn.xml) is used OPMN to manage the services.
Config file location is given as $ORA_CONFIG_HOME/10.1.3/opmn/conf/opmn.xmlServices managed by opmn are 1) HTTP_Server
2) oacore
3) forms
4) oafm
