Programming with Java

Java is best known as a language for writing Web browser appletsthat you call from an HTML document, but Java is also a tool for writing serveror client applications that execute outside a browser context. Althoughquantifying the number of vendors developing Java-based, shrink-wrappedapplications is difficult, many companies are developing Java applications forinternal use on corporate intranets.

One reason for the wave of Java enthusiasm is that Java's architectureemphasizes security and multithreading, so it is well suited for the Webenvironment. Java is Web-aware and understands concepts such as sockets, URLs,and Internet addresses. Java also appeals to developers because of the price ofentry. For example, the primary tools I used to create the insper sample Javaprogram are 32-bit developer libraries available as free downloads. You candownload the Java Developer's Kit (JDK) from JavaSoft's home page athttp://splash.javasoft.com/jdbc and JETConnect Pro from XDB System's home pageat http://www.xdb.com/jet/connect. Microsoft, Sun Microsystems, IBM, Netscape,Borland, Oracle, Sybase, and a long list of other vendors have Java tools indevelopment. Microsoft's Java SDK is available as a free download. Tryhttp://www.microsoft.com/

java for more information. In December 1996,Oracle announced that its SQL products will implement J/SQL, a stored procedurelanguage based on Java.

Microsoft plans to include Java with future releases of its operatingsystems, and Java applets will be widely used plug-in components. Even beforethe Web became the dominant force it is today, Microsoft was pursuing enterprisemarkets by moving beyond a Windows-centric strategy. Java fits well intoMicrosoft's plans with the new orientation toward multiplatform solutions suchas browsers, TCP/IP, HTML, SQL, and Open Database Connectivity (ODBC).

When building the Java SDK and Visual J++ (VJ++), Microsoft supplementedthe reference implementation of the Java interpreter, the Java virtual machine,with classes that let developers use Component Object Model (COM) components.The ability to use existing components means that developers and Web-sitebuilders can use Java within and without the browser.

Despite many promising features, Java does have drawbacks. Download time isa problem for low-bandwidth Web connections. Java's architecture means bytecodesare interpreted, so performance can be an issue. Vendors have been working hardon solutions to the performance problem, including alternatives such ascompiling to native code for time-critical programs. Java's Abstract WindowToolkit doesn't support the diversity of objects available with Borland ObjectWindows Library (OWL) or Microsoft Foundation Classes (MFC), but it lets youcreate a user interface for programs running on Windows NT, Windows 95,Macintosh, Solaris, and other platforms. Java also doesn't offer the rich GUIyou get by using platform-specific features such as property sheets in Windows,although vendors are rushing to create Java toolkits that have GUI components.Symantec Visual Café Pro and XDB JetExpress are part of a new wave ofJava products that provide database connectivity using data-aware controls thatbind database objects to visual components.