Score: 5. This book will get you way up to speed on the technology you'll know it so well, in fact, that you can pass the brand new J2EE 1. If that's what you want to do, that is. Maybe you don't care about the exam, but need to use servlets and JSPs in your next project. You're working on a deadline. You're over the legal limit for caffeine. You can't waste your time with a book that makes sense only AFTER you're an expert or worse, one that puts you to sleep.
Learn how to write servlets and JSPs, what makes a web container tick and what ticks it off , how to use JSP's Expression Language EL for short , and how to write deployment descriptors for your web applications. Master the c:out tag, and get a handle on exactly what's changed since the older J2EE 1.
You don't just pass the new J2EE 1. Head First Servlets and JSP doesn't just give you a bunch of facts to memorize; it drives knowledge straight into your brain. You'll interact with servlets and JSPs in ways that help you learn quickly and deeply. And when you're through with the book, you can take a brand-new mock exam, created specifically to simulate the real test-taking experience.
Score: 4. All Users. If that's what you want to do, that is. Maybe you don't care about the exam, but need to use servlets. Learning a complex new language is no easy task especially when it s an object-oriented computer programming language like Java. You might think the problem is your brain. It seems to have a mind of its own, a mind that doesn't always want to take in the dry, technical stuff. A guide to JavaBeans provides more than two hundred questions and answers to help readers pass the Sun Certified Business Component Developer exam.
If you've read a Head First book, you know what to expect--a visually rich format designed for the way your brain works. If you haven't, you're in for a treat. You'll see why people say it's unlike any other Java book you've ever read. By exploiting how your brain. Both professions require attention to detail, and both practitioners will see their work collapse around them if they make too many mistakes.
It's impossible to imagine a world in which buildings get built without blueprints, but it's still common for software applications to be designed and built without blueprints, or in this case, design patterns. A software design pattern can be identified as "a recurring solution to a recurring problem. But developers have had enough of books that simply catalog design patterns without extending into new areas, and books that are so theoretical that you can't actually do anything better after reading them than you could before you started.
Rather than simply present another catalog of design patterns, the authors broaden the scope by discussing ways to choose design patterns when building an enterprise application from scratch, looking closely at the real world tradeoffs that Java developers must weigh when architecting their applications.
Then they go on to show how to apply the patterns when writing realworld software. Score: 3. Written for novice developers, this book provides an introductory course in web development for undergraduates as well as web developers. Covering Servlet 3. With comprehensive coverage and a lot of examples, this book is a guide to building real-world applications. You'll begin with an introduction to the Java Enterprise Edition and the basic web application, then set up a development application server environment, learn about the tools used in the development process, and explore numerous Java technologies and practices.
Then what? Query stringacpaes, for example, Uh-oh You can design a custom page to handle errors, then use the page directive to configure it. And what if I want a different error page depending on the error? You can declare error pages in the DD for the entire web app, and you can even configure different error pages for different exception types, or HTTP error code types , , etc. That way you can show the client different error pages specific to the type of the problem that generated the error.
Declaring a catch-all error page This applies to everything in your web app—not just JSPs. You can override it in individual JSPs by adding a page directive with an errorPage attribute. The object is type java. Throwable, so in a script you can call methods, and with EL you can access the stackTrace and message properties.
This time, you getabmly details. What if there are some errors I want to catch myself? The one that was actually thrown? But with web app error handling, remember, only officially-designated error pages get the exception object. It puts the exception object into the page scope, under the name you declare as the value of var. Inside the catch. If you bod y. The point is—learn catch or finally block. And on the exam, fooled.
The JSTL is huge. Version 1. But nsformation e. The XML tra give it the delimiter. We have a whole chapter the next one devoted to developing your own custom tag handlers. But the last part of this chapter is about how to use custom tags. What happens, for example, if someone hands you a custom tag library they created for your company or project? How do you know what the tags are and how to use them?
You have to know how to figure out a tag even if the yo documentation is weak or nonexistent, and, eed to Everything you n one more thing—you have to know how to deploy a custom tag library. Main things you have to know: know is in there. You can use any prefix you want, but the name comes from the TLD. The syntax includes things like required and optional attributes, whether the tag can have a body and if so, what you can put there , the type of each attribute, and whether the attribute can be an expression vs.
The URI is what you put in your taglib directive. Besides the function we X M L s c hema that the This says that the tag must NOT have anything in the body. Java class that does the tag work package foo; import javax. JspException; import javax. IOException; things we need in stom tags.
But with custom a custom tag. This must NOTt be a expression Or something that can be implicitly assigned to a Dog reference type. The JSP developer cares most about the uri, the tag name, and the tag tag. Can the tag have a body? Does this attribute have to be a String literal, or can it be an expression? Is this attribute optional?
What type does the expression need to evaluate to? You have to know how to call it and what arguments it needs. By looking through a specific set of locations where TLDs are allowed to live. When you deploy a web app, as long as you put the TLD in a place the Container will search, the Container will find the TLD and build a map for that tag library.
So the next step is for us to see where the Container looks for TLDs, and also where it looks for the tag handler classes declared in the TLDs. There a few issues to keep in mind The reserved prefixes are: jsp: jspx: java: javax: servlet: sun: sunw: Sharpen your pencil Empty tags Write in examples of the THREE different ways to invoke a tag that must have an empty body. Check your answers by looking back through the chapter.
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