Section 23.1. The Politics of Applets


23.1. The Politics of Applets

The potential for applets to add dynamic content to web pages was one of the driving forces behind the spread of the Java programming language. Prior to Java's introduction in 1994, there was really no standard way to do this; even the now ubiquitous animated GIF images were not yet widely supported. Sun's HotJava Java-based web browser was the first to support applets. It was Java's original "killer application." Later, in 1995, Netscape announced that it would support the Applet API in its browsers, and soon after that Microsoft jumped on the bandwagon. For a while, it seemed that Java would flourish on the Web. But there have been some bumps along the road.

Many problems, both technical and political, plagued the early years of Java's use in client-side applications. Performance issues were to be expected in such a young language. But what really crippled Java early on was the nonportable and buggy AWT, Java's original GUI toolkit. Many people overlook the fact that Java's success as a portable language is in large part a result of just how much of the Java API is implemented in Java. You might be surprised to learn just how many Java internals involve no native codeeverything from cryptography to DNS is done in Javarequiring no porting for new platforms. Similarly, the renaissance of Java GUI applications seen in recent years is due almost entirely to the introduction of the pure Java Swing GUI toolkit. In contrast, the original AWT system was based on native code, which had to be ported to each new system, taking into account subtle and tricky platform dependencies. AWT was effectively a large, graphical C program that Java talked to through a set of interfaces and Java was, to some extent, unfairly painted as nonportable and buggy by association.

Java faced other, less technical obstacles as well. Netscape forced the original AWT upon the world when it insisted that Java be released with "native look and feel" in lieu of a less capable, but portable initial toolkit. Later, Microsoft effectively stuck us with this by freezing the level of the Applet API in its browsers at Java 1.1. Applets have been stuck with AWT while lawsuits between Sun and Microsoft have dragged on. The result is that support for applets in web browsers is a mess. There are a lot of applets on the Web today, but they only hint at Java's original promise. There is, however, some light on the horizon.

Sun has made an attempt to insulate Java from the browser battles with the introduction of the Java Plug-in. The Plug-in allows applets to run in an up-to-date Java VM, identically, in all major browsers. But for most browsers, it requires installation by the user, which is less than desirable. More recently, versions of Netscape and Firefox have supported the latest version of Java using the Plug-in directly. As these browsers gain market share, applets become more capable. Newer APIs such as Java Web Start also offer the alternative of simple, zero administration, local installation of Java applications. The latest version of the Java runtime for Java 5.0 consolidates Java Web Start and the Java Plug-in into one package and control panel for the Windows operating system. A relatively painless, one-time install is now all that is necessary to open a variety of options for deploying Java applications to clients.



    Learning Java
    Learning Java
    ISBN: 0596008732
    EAN: 2147483647
    Year: 2005
    Pages: 262

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