Novera Software announced the availability of the most recent release of their application server software at the Java Business Expo in New York in the early part of December. Version 4 of Novera Software's jBusiness application server features a new Component Constructor utility along with a new Management Console and support for Enterprise JavaBeans. The result is a powerful combination that's worth investigating if you are looking to deploy applications using an application server.

Installation and Configuration
I installed the software from CD-ROM, but you can also take a tour of the software using the "jBusiness Experience" link from Novera's Web site. The installation is packaged using InstallShield and I was able to get the software installed and running within minutes. jBusiness is tightly integrated with LDAP, and previous releases of the software required you to have directory services already installed in order to work with the product. To simplify the process of testing the software, Novera offers two installation paths for this new release. If you wish to install the software on a standalone development and deployment machine you can use the Evaluation Installation. Should you wish to work with an LDAP server you can choose the Custom Installation path, which allows you to either configure jBusiness to work with your pre-existing LDAP server or to install the bundled UMICH directory server. The evaluation installation is completely automated, but you'll need to gather some information about your existing LDAP installation if you want to make use of directory services. In both cases you'll need to have a copy of JDK 1.1.6 installed to work with the Business Object Constructor or the Component Constructor.

Novera ships the JRE 1.1.6 run-time environment for the server, but you'll need to download the JDK to work with the tools.

Building an Application
The application server marketplace is getting to be a crowded arena, but Novera is differentiating itself by focusing on their Distributed Business Objects. The jBusiness application server is completely written in Java, and Novera has tested the server on a variety of server platforms including Solaris, HP-UX and Windows NT. Novera's Business Objects are Java classes that have been mapped to relational database objects. Business Objects are further subdivided into two parts, the Business Object Constructor, which is used to create the code and the Business Object Container that performs the database access on behalf of the applications.

The Business Object Constructor interfaces with the relational database, and the first task for any development effort is to connect the constructor interface to your relational database. I was quickly able to connect jBusiness to my existing Oracle database for a fictional university using the latest JDBC thin-client Oracle JDBC driver as shown in Figure 1.

The Business Object Constructor connects to your relational database and allows you to construct Java classes that represent your relational database objects. These objects manage all of the SQL tasks such as generating queries, executing queries and converting query results into Java objects. With this release of jBusiness you can now build a single object that combines information from multiple tables, and a single relational table can be deployed in multiple business objects. This makes it much easier to create custom business objects that accurately represent the manner in which your applications use the underlying data.

The development interface automatically picks up the tables and key definitions for you, but I wasn't able to view database procedures through the mapping facility. Although there is ample documentation for both HTML and PDF format, none of the development and management consoles provide any online help. Developers that are used to having context-sensitive help within the development environment will find this frustrating. Strictly speaking, the Novera product is not a Java application development environment in the same vein as Oracle JDeveloper, Symantec Visual Café or Borland's JBuilder. The Business Object Constructor wraps complex database objects as a series of Java classes, which you can then edit or compile using your favorite Java IDE.

The constructor itself is written in Java and if you are used to working with an IDE that is written in C/C++ you will find that the constructor can be a little slow, although I was able to run both development and deployment on a single machine without any problems. I quickly built several business objects using my sample database, and Novera provides a tutorial guide to help you get up to speed with creating and deploying business objects. This can be a trifle confusing at first and I would recommend that you follow the tutorial the first time through to see how the whole process works. In general, I considered the development environment easy enough to work with for a savvy Java developer, but novices will have a more difficult time getting up to speed.

During the process of creating and deploying your business objects, you're provided with the ability to configure the caching settings for the object. JBusiness offers a sophisticated set of caching options and you can define a particular business object as being either volatile or nonvolatile. The default setting for an object is volatile, which causes the server to read the item from the database automatically when it's referenced within a transaction.

Objects that change frequently, such as inventory levels, are best implemented as volatile objects. On the other side of the equation, business objects that are static in nature such as tables of state codes or part numbers can be delivered as nonvolatile objects, in which case they will be read from the cache. Novera even offers a complete query language for Business Object Containers that allows you to have an incredible level of control over the caching machinations of your objects. The installation CD comes equipped with a number of sample applications, and you can use these as a road map for building and deploying your own applications.

Deploying and Managing Applications
While Novera supports the complete gamut of Web applications, including servlets, it's been designed with object management in mind. The New Management Console (see Figure 2) offers a complete environment for managing your objects and the various services that Novera provides. The emphasis within the management console is keeping track of the various objects that you've put into production. Novera supports the use of multiple application servers and you can easily display configuration information and performance for any of the services that are deployed to the server. The management console itself offers a mix of monitoring tools including charts and graphs, as well as a number of wizards for configuring the application server.

Once I had created my University Business Objects and compiled them, I was able to use a wizard interface within the management console to deploy these objects to the server. Novera is designed as a Java application server and you can connect your jBusiness objects to your favorite Web server. The management interface supports a multi-document style of display so you can monitor multiple windows at the same time, which is a nice feature.

Furthermore, Novera offers an extensive API that you can use to customize the entire management environment. The jBusiness server supports a number of fault-tolerance features such as load balancing, management server failure detection and object method-level failover. I would recommend that you leaf through the extensive System Administrator's Guide before you begin designing your applications so you can get an overview of the complete capabilities of the jBusiness server.

Summary
Novera has made numerous improvements on the latest version of their software, and existing users will be pleased with the additions and changes. The jBusiness product is positioned from a pricing and features standpoint to compete in the Enterprise Application Server space. I would recommend that you evaluate jBusiness if you are looking to build large-scale Java-based server applications. JBusiness is aimed at the seasoned Java developer who is familiar with using and deploying mission-critical distributed applications.

Test Environment
Client/Server: Dell Pentium II 200 MHz, 64MB RAM, 4 Gigabyte disk drive, Windows NT 4.0 (Service Pack 4), ViewSonic 15-inch SVGA monitor, 3COM Etherlink XL Adapter and 8X CD-ROM.

• Figure 1
• Figure 2