3-4 Oracle Fusion Middleware Upgrade Guide for Java EE
Figure 3–3 Comparison of OC4J Groups and Oracle WebLogic Server Clusters
3.1.2 Comparing OC4J and Oracle WebLogic Server Directory Structures
The directory structure of a typical Oracle WebLogic Server domain differs from the directory structure of an Oracle Application Server 10g instance in several ways.
When you install Oracle Application Server 10g, you create a single Oracle home that contains the j2ee directory. The OC4J-specific configuration files and log files reside
inside the j2ee directory.
In Oracle WebLogic Server, the installation is enclosed within a Middleware home. Within the Middleware home, the installer creates the Oracle WebLogic Server home
directory. When you configure a domain, the Oracle WebLogic Server Configuration Wizard creates a new domain inside the user_projects directory.
Figure 3–4 shows the difference between the Oracle WebLogic Server and OC4J
directory structures.
Table 3–1 Comparing OC4J Clustering Features with Oracle WebLogic Server
OC4J Feature Oracle WebLogic Server
Equivalent Feature
More Information
Oracle Application Server cluster topology
Oracle WebLogic Server domain
Understanding WebLogic Server Domains in the Oracle
Fusion Middleware Understanding Domain
Configuration for Oracle WebLogic Server
OC4J groups Oracle WebLogic Server
clusters Understanding WebLogic
Server Clustering and Cluster Architectures in
Oracle Fusion Middleware Using Clusters for Oracle
WebLogic Server
OC4J application clustering Oracle WebLogic Server
HTTP Session State Replication
HTTP Session State Replication in Oracle Fusion
Middleware Using Clusters for Oracle WebLogic Server
Introduction to Oracle WebLogic Server for OC4J Users 3-5
Figure 3–4 Comparison of the Oracle WebLogic Server and OC4J Directory Structures
3.1.3 Understanding Oracle WebLogic Server Domains for OC4J Users
The following sections are designed to help OC4J users learn about the features and capabilities of Oracle WebLogic Server domains:
■
Basic Content and Organization of a Domain
■
Additional Facts About Oracle WebLogic Server Domains
3.1.3.1 Basic Content and Organization of a Domain
Depending on whether you are using 10g Release 2 10.1.2 or 10g Release 3 10.1.3, you organize your Oracle Application Server 10g environment in one of two ways:
■
In Oracle Application Server 10g Release 3 10.1.3, you organize your applications servers and OC4J instances into a cluster topology.
■
In Oracle Application Server 10g Release 2 10.1.2, you can add multiple Oracle Application Server instances into a farm and your OC4J instances into Oracle
Application Server Clusters.
Oracle Fusion Middleware 11g uses an entirely different mechanism to organize your environment. The Oracle WebLogic Server environment is grouped into logical groups
called domains. These domains consist of the following:
■
A single administration server, which is used to manage the domain.
■
One or more managed servers, which are used to deploy the Oracle Fusion Middleware Java components, as well as your custom Java EE applications.
In previous versions of Oracle Application Server 10g, you installed, created, and configured OC4J instances, and one or more Java Virtual Machines JVMs per OC4J
instance.
In Oracle Fusion Middleware 11g, you configure an Oracle WebLogic Server domain with one administration server and one or more managed servers to deploy your Java
EE applications.
