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Virtually any application can be developed using Java, including those that need to issue calls to “system services” such as TCP/IP sockets. Many Integrated Development Environments (IDE) or Rapid Application Development tools (RAD tools) are being announced and released. These tools are often called Java Development Environments (JDE). If you are looking for such products, browse the Usenet newsgroup news://comp.lang.java. Many netizens will be happy to help you locate the best products. You also will have the opportunity to read and post comments to the support people from the companies that develop such programming environments. It has never been easier to get help to make choices before purchasing a development tool. The FutureThe possibilities Java offers are limitless. In the near future, many astonishing applications will appear. You’ll soon see, for example, portable network management tools, interactive communication tools using multimedia techniques, interactive education tools, and information booths. But Java already has impacted operating systems. Many leading industry vendors already endorse the Java technology and include it in their existing platforms. Java made an important impact on the hardware industry, too. Java chips have been announced. They will be used in home appliances and industrial equipment. Many companies have agreed on common network computer specifications. These network computers will have operating systems and operating environments written in Java. Among the main benefits of all these new devices, the most impressive are the low cost and the possibility of on-demand downloading from the network of new versions of the operating elements, for both systems and applications. Java TechnologyJava technology evolves quickly. A Java Electronic Commerce Framework (JEFC), distributable Java components (JavaBeans), and Java/COM (Microsoft’s Compound Object Model) integration are under development. The Java Database Connectivity API (Application Programming Interface), Java Object Serialization, and Java Remote Method Invocation are already available. Concerning JDBC (Java Database Connectivity), JavaSoft (Sun Microsystems) and partners have plans for a Java Object-Relational Mapping API and for a Java Transaction Service API. The ODMG (Object Database Management Group) has been working on a standard API for Java object databases. This standard will be finalized by the time you read this book. Java ApplicationsCertain Java applications are worth mentioning. Both the Java-enabled Transaction Processing Monitor and the Java CASE Tool are of interest for the database developer going the Java way. Example: Transaction Processing Monitor One of the most interesting available products is a Transaction Processing (TP) monitor that works with Java clients. A client/server environment can include a TP monitor when the servers are Database Management System server. It solves the problems that arise when hundreds, or even thousands, of clients send requests to a database server at the same time. The product is Vortex Java Edition, from Trifox, Inc. Transaction processing monitors have existed for a long time. They were available for every mainframe environment. When the X/Open XTP Group’s DTP model appeared, these monitors evolved to systems that guarantee their integration with open environments and that guarantee their interfacing with various components of distributed systems. The TP monitor is a special kind of middleware that offers services related to the application level. These services are transaction oriented. The TP Monitor is a middleware between clients and servers as shown in Figure 1-1.
The TP monitor’s roles are to:
The monitor’s primary role is to dispatch transactions to one or multiple DBMS servers, allowing many clients to operate seamlessly. Common DBMSs are unable to handle thousands of simultaneous connections and process their queries. TP monitors solve the problem by reducing the number of active sessions necessary to process the client requests. They are probably the most advanced element of traditional client-server architectures where relational databases are involved. In the Internet scenario, the high number of clients that can potentially initiate a connection to a server makes the TP monitor middleware an interesting element of the client-server architecture. The availability of Java-enabled TP monitors shows that there are no limits to what is possible using the Java language, the Java environment, and traditional elements of client-server systems. Another Example: A Java CASE Tool Another interesting product is Platinum Technology, Inc.’s Paradigm Plus code generator. It is a Computer Aided Software Engineering tool (CASE tool) that supports object-oriented analysis, design, and modeling, as well as reverse engineering from other languages. From conceptualization to deployment, it promotes component sharing and reuse across projects in the enterprise. The product supports all leading object-oriented methodologies and notations, and more — it allows developers to customize methods based on their specific requirements. Among Paradigm Plus’s many characteristics, the most interesting are its:
One feature, the generation of DBMS and ODBMS schema definitions, may be of particular interest to JDBC users. Indeed, the physical database design for persistent data may be done within this environment, and the result can then be applied within the DBMS. JavaSoft’s (Sun Microsystems) JavaPlan is a similar software engineering tool. There is no doubt that such complete, robust, and flexible products will help the analyst and developer during their Java projects. This is only the beginning of a new era and products like the CASE tool will soon emerge in all-Java or Java-enabled versions. SummaryJava is definitely well suited for networked computing, and is complete enough to build robust, enterprise-class applications and applets. The next chapter discusses fundamental database concepts such as SQL and database access interfaces.
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