Ajax applications have unique design and architectural challenges and opportunities. This presentation will show you how to take advantage of the Ajax's strengths, and work around its quirks.

We'll start with an overview of Ajax, and then dive right into an extended example where we add Ajax to an existing web application. Along the way we'll cover several tools that we use to aid in Ajax development: The JavaScript Shell, Firebug, and the Web Developer's Toolbar. We'll also look at two popular JavaScript Ajax libraries: Prototype and Scriptaculous.

With the example application under our belts, we'll move to a discussion of Ajax architectural questions, including:

How do I select an Ajax library? What format data should my Ajax calls use: XML, JSON, HTML, or other? How do I handle the back button and deep linking in Ajax? Prior exposure to Ajax and JavaScript is useful but not required.

With the sudden importance of Ajax, it's time to take JavaScript seriously. That means learning it the right way: looking at the fundamentals of the language and surveying its strengths and weaknesses, instead of just copying other people's poorly written examples.

JavaScript got a bum rap. It's almost universally derided among serious programmers for being a toy language, or for its strange characteristics, or bugs, or slowness, or because it's only good for adding useless window dressing to web pages.

But JavaScript is actually a very nice little language which is popping up everywhere these days (not just in Ajax apps). Sure, JavaScript is quirky, but its problems are mostly due to history, association, and misunderstanding. Especially misunderstanding. Let's face it: most developers learned JavaScript by looking at examples in web pages they found online, and few of those examples are paragons of JavaScript style. Other developers learned JavaScript from books, but the typical JavaScript book ignores the fundamentals of the language, instead focusing on examples and the fastest ways to do fancy web page tricks.

In this talk, we'll go back to the basics that most JavaScript resources omit. We'll talk about JavaScript as a language, learning its fundamental concepts and the simple rules that underlie the sometimes bewildering behavior.

Building on part 1, this talk dives deep into JavaScript's object model. We'll see how it differs from more mainstream object-oriented languages, and why. We'll explore how to hide some of those differences, as well as the reasons you might not want to. Additionally, we'll cover useful tools for JavaScript testing, debugging, and profiling.

Ajax is not the focus of this talk, but a strong foundation in JavaScript is essential for working with Ajax.

Performance myths about the Java platform abound, from the general "Java is slow", to the more specific "reflection is slow", "allocation is slow", "synchronization is slow", "garbage collection is slow", etc. Many of these myths have their root in fact (in JDK 1.0, everything was slow); today, not only are many of these statements not true, but Java performance has surpassed that of C in many areas, such as memory management.

In this class, we'll look at some common Java performance myths, identify where they came from, and explore the platform changes that have rendered them no longer true. Many common performance hacks don't actually help, and some can seriously hurt performance. The result is that clean code that follows common usage patterns generally shows far better behavior on modern JVMs than code laden with tweaks designed to "help" the JIT or garbage collector. More often than not, this well-intentioned assistance has the unfortunate effect of undermining many common JIT optimizations, resulting in slower -- not faster -- code.

The early years of computers -- the '50s and '60s -- were characterized by furious exploration of a huge variety of different ideas. Since then many of the hot topics of those days have moved to the fringe, largely ignored by the mainstream of software development. But some of them are being rediscovered, and a lot of what we think of as "new developments" are really just some old ideas returning to center stage.

This talk will trace the roots of some contemporary software trends back to their origins before most of us were born.