Chapter 1 About Enterprise Application Server

What is Enterprise Application Server?

EAServer is an integrated set of development tools and application servers that you use to deploy Web applications that support high-volume traffic, dynamic content, and intensive online transaction processing (OLTP). EAServer consists of PowerDynamo, Jaguar CTS, Application Integrator for CICS, Application Integrator for Stored Procedures, Adaptive Server Anywhere, and PowerJ.

Note   For detailed information about each product, see the individual product documentation.

Dynamo is an application server that dynamically generates HTML pages, which are in turn delivered to Web browsers through an HTTP protocol.

Jaguar is an application server that serves up business logic components and dynamic HTML generated by servlets and JavaServer Pages (JSPs). Jaguar supports thin Web clients using HTML forms or Java applets, and standalone clients. Clients can be implemented using PowerBuilder, Java (CORBA or Enterprise JavaBeans), ActiveX, C++, or even using the MASP (Methods As Stored Procedures) interface.

Components are reusable modules of code that combine related tasks (methods) into a well-defined interface. Jaguar components are installed on a Jaguar server and contain the methods that execute business logic and access data sources. You (or your administrator) install the component's executable code on the Jaguar server. Components can be distributed throughout a network (including the Internet or an intranet) on different servers. Installed components can be used by any number of independent applications.

Adaptive Server Anywhere is a full-featured, transaction-processing DBMS. It has excellent performance while requiring fewer resources (memory, disk space, and CPU cycles) than other DBMSs. Adaptive Server Anywhere is used in conjunction with Dynamo and Jaguar. Adaptive Server Anywhere holds your corporate data, which is retrieved and updated by Dynamo and Jaguar.

Both Application Integrator for CICS (AI for CICS) and Application Integrator for Stored Procedures (AI for Stored Procedures) are Jaguar component development and deployment tools that make it easy to integrate enterprise data sources with Jaguar. Similarly through the Visual Edge® product, GoldenGate™ for EAServer, you can easily integrate SAP™ business objects with Jaguar. Java developers can create Jaguar components that execute business logic in mainframe COBOL programs or stored procedures in databases that reside on mainframes, PCs, or workstations. Jaguar clients can execute methods in these components, which, in turn, execute the corresponding COBOL programs or stored procedures.

You can use Dynamo and Jaguar separately, or you can use them together. You may use many different development tools (PowerJ, PowerBuilder, Visual Basic, Visual C++) and component models (Java/Enterprise JavaBeans/Java Servlets, ActiveX, CORBA C++, PowerBuilder NVO, and a C "pseudo" component model) to develop middle-tier OLTP components and deploy them on a Jaguar server. You can use Dynamo to deploy your thin-client Web applications and Dynamo tags and scripts to call the component methods on the Jaguar server. Information is returned to the application in the form of dynamically generated HTML.

EAServer features

EAServer contains these features that make deploying Web sites and OLTP applications quick and easy to upgrade:

EAServer documentation

EAServer documentation consists of these books:

Jaguar overview

Jaguar is for deploying transaction-intensive business applications on the Internet. These applications move beyond one-way dynamic updates or data collection to real-time two-way updates of business critical information. You can also migrate traditional client/server transactional applications to multitier Jaguar applications.

Jaguar provides a framework for deploying the middle-tier logic of distributed component-based applications. Jaguar is the industry's only component transaction server based on open computing standards. It combines the features of a transaction-processing monitor and an object request broker to give you an easy-to-use package for rapidly deploying transactional applications. With Jaguar, developers can focus on solving business problems instead of programming the application's infrastructure. At the heart of Jaguar is a high-performance transaction server that provides efficient management of client sessions, security, threads, database connections, and transaction flow. Jaguar's scalability and platform independence allow you to develop your application on inexpensive uniprocessor machines, then deploy the application on an enterprise-grade multiprocessor server.

Client-side logic for enterprise applications must be as small and efficient as possible to conserve network bandwidth. To accomplish this goal, applications are partitioned into three parts: presentation logic, business logic, and database logic. The database resides on the bottom tier of the enterprise system to maintain and secure the organization's information assets. The business logic resides in the middle tier or component transaction server. The presentation logic is on the user's desktop, or top tier, or is dynamically downloaded to the user's desktop.

The transaction server is then responsible for executing and securing the vast majority of a corporation's business logic. This makes it a critical component in the emerging network-centric architecture. The Web browser connects to Jaguar or a Web server via HTTP to download an HTML page containing a Java applet that performs presentation functionality. The applet communicates with Jaguar, calling middle-tier components that perform business logic. Middle-tier components can use Sybase's Client-Library, ODBC, or JDBC to communicate with a third-tier DBMS. The DBMS stores, processes, and protects the corporate data. Jaguar manages a pool of connections to the back-end database, coordinating the transaction processing to those servers.

Components are objects that reside on a server (a Jaguar server, for example) and can be used by many different programs, regardless of the program's programming language. A client executes the methods in a component. Instead of creating one massive program, you create a client that contains the GUI and validation code and several individual components that contain the functionality (or business logic) of your program. By separating the functionality from the GUI, you can easily upgrade and change the functionality of your program without having to change the GUI. In addition, multiple clients (including Dynamo) can use components at the same time.

With Jaguar, you can:

Jaguar provides the following additional services:

For more information

For more information, see the Jaguar documentation, which includes these books:

What you need to know before using Jaguar

To use Jaguar effectively, you should be able to create programs in at least one of the following programming languages or component models:

You should also know how to retrieve and update information in databases and be familiar with component technology concepts.

Dynamo overview

Dynamo is perfect for implementing thin-client Web applications for an Internet or intranet site that can support millions of hits per day. Dynamo provides the tools necessary to build and manage a thin-client Web application containing both static HTML and dynamic, data-driven content.

Not only does Dynamo leverage a powerful object-oriented scripting language called DynaScript, but Dynamo applications can be extended to call any component supported by EAServer. The Dynamo application server acts as an intermediary between the Web server and the DBMS. The application server processes templates, which are HTML pages with embedded SQL or COMPONENT statements and DynaScript scripts, and serves the resulting output together with static HTML to the Web server. In addition, Dynamo's unique use of the database as a Web repository allows for entire applications to be distributed using existing database replication facilities.

With Dynamo, you can:

Dynamo provides the following additional services:

Dynamo is available on AIX with NSAPI, CGI and the Personal Web Server. CGI and the Personal Web Server are available on Solaris (NSAPI is supported from previous Dynamo releases).

For more information

For more information, see the PowerDynamo documentation, which includes these books:

What you need to know before using Dynamo

To use Dynamo effectively, you need to be moderately familiar with Web technology such as HTML (Hypertext Markup Language), ECMAScript, and the operations of Web browsers and servers. You should also be somewhat familiar with SQL (Structured Query Language), and using databases.You do not need to know DynaScript before using Dynamo. Dynamo includes tutorials and clear examples of using DynaScript.

Benefits of using Jaguar components with PowerDynamo

Jaguar components can be called from within a Dynamo script as though they were stored procedures, Java objects, or ActiveX objects. The type of component being accessed is irrelevant to the client. As long as the client has been set up properly to access the component, Dynamo scripts can be written to use Jaguar components as though a stored procedure was being called (referred to as the MASP feature in Jaguar) or by creating an instance of a Java or ActiveX object.

The three main benefits to using Jaguar components in Dynamo scripts are:

The way in which Jaguar components are independently accessible by clients such as Dynamo is advantageous because no restrictions have been put on the way in which the client can manipulate the component results. The component results are wholly controlled by the client which, in the case of Dynamo, is by HTML pages.

The ability to access these components at one central repository is extremely appealing from a setup point of view. Setting up Dynamo to access Jaguar components can be as simple as creating a connection to the Jaguar server or installing the ActiveX proxy automation server. A brief summary on setting up clients to access Jaguar is given in Chapter 4, "Using PowerDynamo with Jaguar". For detailed information on setting up clients that require Jaguar access, see the Jaguar CTS Programmer's Guide.

Adaptive Server Anywhere overview

Adaptive Server Anywhere is included with EAServer to provide a full-featured SQL database for Jaguar applications. Adaptive Server Anywhere is designed to operate in environments with limited physical and database administration resources.

Adaptive Server Anywhere is a transaction-processing relational database management system (RDBMS) with full recovery capabilities, online backup, referential integrity actions, stored procedures, triggers, row-level concurrency control, and a rich SQL language. In addition, Adaptive Server Anywhere contains the following features:

For more information

For more information, see the Adaptive Server Anywhere documentation, which includes these books:

For basic information about databases, see First Guide to SQL Anywhere Studio in SQL Anywhere Studio. Although SQL Anywhere Studio is not included in EAServer, you can view First Guide to SQL Anywhere Studio on the Sybase Product Manuals Web site .

Application Integrator overview

AI for CICS and AI for Stored Procedures enables Jaguar to access stored procedure and mainframe COBOL programs. You use the AI Component Builder to create components from COBOL programs and stored procedures without any coding. From within the Component Builder, you can quickly deploy the components to a Jaguar server.

Through GoldenGate for EAServer, Jaguar components can access SAP business objects. GoldenGate for EAServer is third-party software that you must purchase separately. Once you have installed GoldenGate for EAServer and have access to SAP business objects, you generate and install proxy components for the corresponding SAP business objects onto a Jaguar server. You can invoke the SAP proxy component interface from any CORBA, EJB, COM, or PowerBuilder component using Java, C++, or PowerBuilder. For more information about GoldenGate for EAServer, see the documentation that accompanies the software.

In addition to Sybase database stored procedures, you can use AI for Stored Procedures to execute:

For more information

For more information, see the Application Integrator documentation, which includes these books:

What you need to know before using Application Integrator

To use AI for CICS effectively, you should be moderately familiar with Jaguar and know about:

To use AI for Stored Procedures effectively, you should be moderately familiar with Jaguar and know:

To use AI for SAP effectively, you should be moderately familiar with Jaguar and know:

PowerJ overview

PowerJ is Sybase's RAD tool for Java development. Even if you are not an experienced Java programmer, you can use PowerJ to write sophisticated programs. If you are an experienced Java programmer, you can use the full facilities of Java whenever necessary.

Because PowerJ provides facilities that let you build and deploy components directly to the middle tier, it is the ideal web development environment for EAServer.

With PowerJ, you can:

 

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