理解Oracle Fusion Middleware中的关键概念

两种类型的组件：

Oracle Fusion Middleware provides two types of components:

• A Java component, which is an Oracle Fusion Middleware component that is deployed as one or more Java EE applications and a set of resources. Java components are deployed to an Oracle WebLogic Server domain as part of a domain template（java组件被部署到weblogic服务器上，作为域模板的一部分）. Examples of Java components are the Oracle SOA Suite and Oracle WebCenter Portal components.

• A system component, which is a manageable process that is not deployed as a Java application. Instead, a system component is managed by Oracle Process Manager and Notification (OPMN).（比如R12.1里面的form，oacore进程）

A Java component and a system component are peers（对等的，同辈的）.

After you install and configure Oracle Fusion Middleware, your Oracle Fusion Middleware environment contains the following:

• An Oracle WebLogic Server domain, which contains one Administration Server and one or more Managed Servers.The Administration Server contains Oracle WebLogic Server Administration Console and Fusion Middleware Control.The Managed Servers contain components, such as Oracle WebCenter Portal and Oracle SOA Suite as shown in Figure 1-1.（admin server里面有weblogic控制台和fusion middleware control；managed server包含java组件，比如WebCenter Portal、SOA Suite）

  See Section 2.5 for information about Oracle WebLogic Server domains.

• One or more Oracle instances, if your environment includes system components. See Section 2.6 for information about Oracle instances.

• A database that is used as a metadata repository, if the components you installed require one. For example, Oracle SOA Suite requires a metadata repository. See Section 2.7 for information about metadata repositories.

什么是Middleware Home，Oracle Home、Oracle Common Home？

A Middleware home is a container for the Oracle WebLogic Server home, and, optionally, one Oracle Common home and one or more Oracle homes. A Middleware home can reside on a local file system or on a remote shared disk that is accessible through NFS.

下面是一个安装了soa的home结构：

An Oracle home contains installed files necessary to host a specific component or software suite. An Oracle home resides within the directory structure of the Middleware home. Each Oracle home can be associated with multiple Oracle instances or Oracle WebLogic Server domains. There can be multiple Oracle homes within each Middleware home.
按照上面描述的理解，如果多装几个组件，应该会有多个oracle home。

The Oracle Common home contains the binary and library files required for Fusion Middleware Control and Java Required Files (JRF). There can be only one Oracle Common home within each Middleware home.

A WebLogic Server home contains installed files necessary to host a WebLogic Server. The WebLogic Server home directory is a peer of Oracle home directories and resides within（内嵌于） the directory structure of the Middleware home.

domain home：The top-level directory of an Oracle WebLogic Server administration domain is referred to as the domain home. The directory structure of a domain is separate from the directory structure of the WebLogic Server home. A domain home can reside anywhere; it need not be within the Middleware home directory.

An Oracle WebLogic Server administration domain is a logically related group of Java components. A domain includes a special WebLogic Server instance called theAdministration Server, which is the central point from which you configure and manage all resources in the domain. Usually, you configure a domain to include additional WebLogic Server instances called Managed Servers. You deploy Java components, such as Web applications, EJBs, and Web services, and other resources, to the Managed Servers and use the Administration Server for configuration and management purposes only.

A domain is a peer of an Oracle instance. Both contain specific configurations outside of their Oracle homes.

按照上面描述的理解，如果多装几个组件，应该会有多个oracle home。