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.Remember, the Java support in Navigator is built-in, so you don't have to do anything special to get it working.As a result, you can immediately start viewing and interacting with Java-enhanced Web sites.The only real Java-specific option in Navigator is whether or not you want Java support enabled.Most of the time you will want to leave Java support enabled, so that you can enjoy the benefits of the Java technology.However, if you are experiencing problems with Java or with a particular Java Web site, you can disable Navigator Java support.To do this, select the Security Preferences command from the Navigator Options menu.The Disable Java checkbox is used to enable/disable Java support.Figure 8.3 shows the Navigator Security Preferences dialog box.If Java is disabled, you will still be able to view Java-enhanced Web sites, you just won't be able to view or interact with the Java applets contained within them.The Netscape Navigator Security Preferences dialogue box.Java AppletsThere are already many Java applets available for you to run and try out, ranging from games to educational instruction.Most of them come with source code, so you can use them as references for your own Java programs.Figure 8.4 shows a crossword puzzle Java applet running in Netscape Navigator.A crossword puzzle Java applet running in Netscape Navigator.The different applications for Java are limitless.Figure 8.5 shows a very interesting application of Java: an instructional dance applet.An instructional dance Java applet running in Netscape Navigator.If you want to check out some of the Java applet demos, take a look at the Java Applet Demos Web page on Netscape's Web site, which is shown in Figure 8.6:Netcape's Java Applet Demos Web site.If you want to find out more about creating your own Java applets that can be integrated into Web pages, check out Part V of this book, “Applet Programming.”JavaScriptJavaScript is a scripting language described by Netscape as a lightweight version of Java.JavaScript promises to enable less technical Web users and developers the capability to create interactive content for the Web.You can think of JavaScript as a higher level complement to Java.Netscape Navigator supports JavaScript by providing an internal JavaScript interpreter.JavaScript was designed with the goal of creating a simple and easy-to-use cross-platform scripting language that could connect objects and resources from both HTML and Java.While Java applets are primarily developed by programmers, JavaScript is intended to be used by HTML document authors to dynamically control the interaction and behavior of Web pages.JavaScript is unique in that is has been designed to be complementary to both HTML and Java.If you can believe it, JavaScript is actually an even newer technology than Java.Because JavaScript was developed jointly by Sun and Netscape, it is almost guaranteed to be widely adopted by the Web community.However, it may still take some time before you see truly compelling applications of JavaScript.Part IX of this book, “JavaScript,” is entirely devoted to understanding and using JavaScript.SummaryThe latest release of Netscape's line of Web products promises to further establish Netscape as the premier Web tool provider.A central technology present in these tools is Java, which brings interactivity to the Web.Netscape Navigator, along with already being the most popular Web browser available, is the first major Web browser to fully support Java.In this chapter, you learned about the different tools available from Netscape and how Java relates to them.You also learned about JavaScript, and how it is positioned to provide a higher level option to HTML developers wishing to add interactivity without learning Java inside and out.Netscape's early support for both Java and JavaScript is a sure sign that these technologies are here to stay.Now that you have an idea about how the most popular Web browser supports Java, you may be interested in learning about a new browser developed by the creators of Java, Sun Microsystems.The next chapter takes a close look at HotJava, Sun's new Web browser that is tightly integrated with Java.Chapter 9HotJavaJava applets are only as useful as the Web browsers that support them.Although Netscape Navigator is certainly a strong contender for the Java support crown, Sun has its own browser that is specifically designed with Java in mind: HotJava.The HotJava Web browser builds on the techniques established by NCSA Mosaic and Netscape Navigator, while adding the capability to add new behaviors dynamically.The tight link to the Java language is what enables HotJava to have this dynamic behavior.In this chapter, you learn all about HotJava, including its major features and how to install and use it.Although HotJava as a software product is still in the development stages, it is readily available and quite usable in its current alpha form.This chapter explores the primary features of HotJava and how they impact Web navigation and the Java language.This Is HotJavaBefore getting into the specifics of how to install and use HotJava, it's important to take a look at why HotJava is important.Actually, if you first want to literally take a look at HotJava, check out Figure 9.1.The HotJava Web browser.Figure 9.1 shows what HotJava looks like.You'll learn about how to use HotJava a little later in this chapter.For now, it's important to understand why HotJava is significant as a Web browser.There are a variety of technical innovations in HotJava that promise to make it more extensible than other Web browsers.These innovations stem largely from the fact that HotJava is designed around supporting the Java language.The primary innovation that sets HotJava apart from other browsers is its extensibility.Where other browsers have most or all of their components hardwired to the executable browser application, HotJava opts for a more distributed approach.This means that by itself, HotJava doesn't really support any object types or Internet protocols.But its extensible design provides a very open path to add support without modifying the HotJava application itself.Furthermore, HotJava can be extended to provide new support automatically and on demand without the user even having to know.Following is a list of the major features in HotJava:lDynamic Object TypesllDynamic ProtocolsllNetwork SecuritylDynamic Object TypesAlong with dynamic content within Web pages, HotJava also aims to be dynamic on a few other fronts.One of these fronts is the support for dynamic object types.An object type refers basically to a file format, such as the popular GIF (Graphics Interchange Format) graphics files.Although most Web browsers provide support for the most popular object types right now, who's to say what new object types will appear in the future? Obviously no one knows what object types will become popular in the future.For this reason, HotJava takes an open-ended approach to supporting object types.HotJava is capable of dynamically linking to Java code for handling a particular object type on the fly
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