Building Analytical Java Applications

Java is the language of the Internet. Using Java, an application developer can write a standalone application or an applet, which is a program that can be included in an HTML page and executed in a browser.

About Java

Java is the preferred programming language for an ever-increasing number of professional software developers. For those who have been programming in C or C++, the move to Java is easy because it provides a familiar environment while avoiding many of the shortcomings of the C language. Developed by Sun Microsystems, Java is fast superseding C++ and Visual Basic as the language of choice for application developers for the following reasons:

• Object oriented. Java allows application developers to focus on the data and methods of manipulating that data, rather than on abstract procedures; the programmer defines the desired object rather than the steps needed to create that object. Almost everything in Java is defined as an object.
• Platform independent. The Java compiler creates byte code that is interpreted at runtime by the Java Virtual Machine (JVM). As the result, the same software can run on all Windows, Unix, and Macintosh platforms where the JVM has been installed. All major browsers have the JVM built in.
• Network based. Java was designed to work over a network, which allows Java programs to handle remote resources as easily as local resources.
• Secure. Java code is either trusted or untrusted, and access to system resources is determined by this characteristic. Local code is trusted to have full access to system resources, but downloaded remote code (that is, an applet) is not trusted.

  The Java "sandbox" security model provides a very restricted environment for untrusted code. For example, untrusted Java code cannot read to or write from files on the local file system, run programs, load libraries, define native method calls, or make network connections except to the originating host computer. A security manager determines the system resources that an applet can access. However, a signed applet, which identifies itself as being from a trusted source, has full access to system resources the same as local code.

Deploying Java Applications

With the rise in Internet technology, more and more businesses are recognizing the savings they can accrue just by changing the way they deploy their applications.

Traditional thick client applications implement many of their functions on the user's computer, thus requiring a large proportion of installed code. However, the days are gone when a team of technicians are required to install and maintain applications software on hundreds or thousands of individual desktop computers for a large user base. Instead, Java thick-client applications download the needed software to client computers automatically at run-time.

Alternatively, system administrators can deploy thin client applications that do not download any Java to client computers. These applications run on servers that users world wide can access using Java clients such as their Web browsers. By deploying thin client business intelligence applications on the Internet, businesses can distribute information both within their enterprise and externally to suppliers and customers.

Regardless of whether you choose a thick-client or a thin-client configuration, Java applications provide an immediate solution to the problems inherent in supporting large user communities, which typically are equipped with a variety of incompatible hardware and software platforms.

The Java Solution for OLAP

To develop an OLAP application, you can use the Java programming language. Java enables you to write applications that are platform-independent and easily deployed over the Internet.

The OLAP API is a Java-based application programming interface that provides access to multidimensional data for analytical business applications. The OLAP API fetches data stored in a data warehouse into the OLAP multidimensional data cache for manipulation by its analytical engine. Java classes in the OLAP API provide all of the functions required of an OLAP application: Connection to an OLAP instance; authentication of user credentials; access to data in the RDBMS controlled by the permissions granted to those credentials; and selection and manipulation of that data for business analysis.

The BI Beans simplify application development by providing these functions as JavaBeans. Moreover, the BI Beans include JavaBeans for presenting the data in graphs, crosstabs, and tables.

Oracle Java Development Environment

Oracle JDeveloper provides an integrated development environment (IDE) for developing Java applications. Although third-party Java IDEs can also be used effectively, only JDeveloper achieves full integration with the Oracle database and BI Beans wizards. The following are a few JDeveloper features:

• Remote graphical debugger with break points, watches, and an inspector.
• Multiple document interface (MDI)
• Codecoach feature that helps you to optimize your code
• Generation of 100% Pure Java applications, applets, servlets, Java beans, and so forth with no proprietary code or markers
• Oracle database browser

For more information about the Java programming language, browse the Sun Microsystems Java Web site at http://java.sun.com. For information about JDeveloper, search the Oracle Web site at http://www.oracle.com.