Java ES Components

Java ES is an integration of discrete software products and components into a single software system. This integration is facilitated by a number of system-level features, as listed below:

• All components are synchronized on a common set of shared libraries.

• All Java ES components are installed using a single installer.

• All Java ES components can share an integrated user identity and security management system.

• All Java ES components have a common monitoring framework.

These features are described in subsequent chapters of this book. The focus of this section is to introduce the components that are integrated into Java ES. These system components can be grouped into three main categories, as shown in the following figure.

Figure 1–2 Categories of Java ES Components

The components provide services as follows:

• System service components. These components provide the main Java ES infrastructure services that support distributed enterprise applications.

• Service quality components. These components enhance the availability, security, scalability, serviceability and other components of system service components and distributed application components.

• Shared components. These components provide the environment in which many system service components and service quality components run.

For a list of Java ES components, see Appendix A, Java ES Components.

System Service Components

A number of Java ES components provide the main services that support distributed software solutions. These system services include portal services, identity and security services, web container services, J2EE application services, and persistence services.

The system service components that provide these distributed services and the services they provide are listed alphabetically and briefly described in the following table. Each system service component is a multithreaded server process capable of supporting a large number of clients. For more details on each component, see System Service Components.

Table 1–1 Java ES System Service Components

Component	System Services Provided
Sun Java System Access Manager	Provides access management and digital identity administration services. Access management services include authentication (including single sign-on) and role-based authorization for access to applications and/or services. Administration services include centralized administration of individual user accounts, roles, groups, and policies.
Sun Java System Application Server	Provides J2EE container services for Enterprise JavaBeansTM (EJB) components, such as session beans, entity beans, and message-driven beans. The container provides the infrastructure services needed for tightly coupled distributed components to interact, making the Application Server a platform for the development and execution of e-commerce applications and web services. Application Server also provides web container services.
Sun Java System Directory Server	Provides a central repository for storing and managing intranet and Internet information such as identity profiles (employees, customers, suppliers, and so forth), user credentials (public key certificates, passwords, and pin numbers), access privileges, application resource information, and network resource information.
Java DB [Java ES 5 is the first release to include Java DB as a product component. Java DB was first released as a shared component named Derby Database and was included in Java ES 2005Q4.]	Provides a lightweight database for Java application development. Java DB is Sun's supported distribution of the open source Apache Derby 100% Java technology database.
Sun Java System Message Queue	Provides reliable, asynchronous messaging between loosely coupled distributed components and applications. Message Queue implements the Java Message Service (JMS) API specification and adds enterprise features such as security, scalability, and remote administration.
Sun Java System Portal Server	Provides key portal services, such as content aggregation and personalization, to browser-based clients accessing business applications or services. Portal Server also provides a configurable search engine.
Sun Java System Service Registry	Provides a registry and repository to support web service-oriented architecture (SOA) applications. Service Registry implements industry standards for registering and discovering web services as well as for managing the associated information and facts, artifacts, such as XML schema, business process rules, access control, version control, and so forth.
Sun Java System Web Server	Provides J2EE web container services for Java web components, such as Java servlet and JavaServer PagesTM (JSPTM) components. Web Server also supports other web application technologies for delivering static and dynamic web content, such as CGI scripts and Sun Java System Active Server Pages.

Service Quality Components

In addition to the system service components shown in Table 1–1, Java ES includes a number of components used to enhance the quality of services provided by system service components. Service quality components can also enhance custom-developed application services. The service quality components fall into the following categories:

• Availability components

• Access components

• Monitoring components

Availability Components

Availability components provide near-continuous uptime for system service components and custom application services. The availability components included in Java ES and the services they provide are shown in the following table. For more details on each component, see Availability Components.

Table 1–2 Java ES Availability Components

Component	Availability Services Provided
High Availability Session Store	Provides a data store that makes application data, especially session state data, available even in the case of failure.
Sun Cluster	Provides high availability and scalability services for Java ES, the applications that run on top of the Java ES infrastructure, and the hardware environment in which both are deployed.
Sun Cluster Geographic Edition [Java ES 5 is the first release to include Sun Cluster Geographic Edition as a Java ES product component.]	Protects applications from unexpected disruptions using multiple clusters that are geographically separated and a redundant infrastructure that replicates data between these clusters. Sun Cluster Geographic Edition software is a layered extension of Sun Cluster software.

Access Components

Access components provide front-end access to system services, often secure access from Internet locations outside an enterprise firewall. In addition to providing such access, many provide a routing and caching function as well. The access components included in Java ES and the services they provide are shown in the following table. For more details on each component, see Access Components.

Table 1–3 Java ES Access Components

Component	Access Services Provided
Sun Java System Portal Server (includes Secure Remote Access)	Provides secure, Internet access from outside a corporate firewall to Portal Server content and services, including internal portals.
Sun Java System Web Proxy Server	Provides for caching, filtering, and distribution of web content for both outgoing and incoming Internet requests.

Monitoring Components

Java ES includes a new monitoring feature that provides real-time system status and customizable monitoring jobs. Monitoring is implemented by the Sun Java System Monitoring Console product component, which is supported by the Sun Java System Monitoring Framework shared component. For more information, see Monitoring Components.

Shared Components

Java ES includes a number of locally installed shared libraries upon which many system service components and service quality components depend. Java ES shared components provide local services to Java ES product components running on the same host computer.

Shared components are often used to provide portability across different operating systems. Examples of Java ES shared components include: Java 2 Platform, Standard Edition (J2SE), Netscape Portable Runtime (NSPR), Network Security Services (NSS), Java Security Services for Java (JSS), and so forth. For a complete list, see Shared Components.

Shared components are installed automatically by the Java ES installer depending on the system service and service quality components that are being installed.