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J2EE Design Patterns
If you are working on frameworks, integration projects or system components, it is my belief that you'll almost certainly pick up some ideas from this book. J2EE Design Patterns is organized according to the different layers that you might find in a multi-tier architecture: presentation, business, database, messaging, and others. Consequently, if you're a JSP developer on a project team, youll be able to get some ideas for how to organize your work as well as how to interface it with, for example, controllers, if you're following an MVC framework. Or, if you're integrating various distributed non-Java systems, you'll want to read the chapters on Business Tier Interfaces and Enterprise Concurrency.
Judging by my friends' bookshelves, another popular Java patterns book is Core J2EE Patterns. If you already own this book, you will find that this new offering from O'Reilly doesn't contain as many patterns per se, but seems to go into a greater level of detail describing each pattern and supplementing it with more code samples. A nice feature of the O'Reilly book is that each pattern gets ample coverage in enough detail for you to understand the actual problem, the causes and -- equally importantly -- how to put a solution into place. Each pattern is described using some UML notation and code samples (Chapter 2 contains a UML primer).
One of the problems that I've encountered reading books on the subject is that some steer so deeply into abstraction that they become hard to understand. Others are so stylistically repetitive that trying to read them becomes mind numbing. Fortunately, neither problem surfaced during the time that I spent reading this book. The authors avoided the visual repetition of the traditional Problem / UML / Goal / Actors format that other books follow by moving this type of description into an appendix. That lets the body of the book flow more easily and also supplies the reader with a handy quick reference in the back pages.
Do I have any complaints? Well, this book certainly doesn't suffer from any fatal flaws. But it seems that an acknowledgement of the popularity of certain components could have been included. For example, while specific MVC frameworks, like the ubiquitous Struts, were mentioned, Object-Relational mappers were not; I read some of the chapters and winced at the code samples that manipulated SQL strings and felt grateful that I'm using the wonderful Hibernate O/R mapping engine. Of course, for various reasons, some readers won't be able to use tools like these, and a book about patterns has to maintain a certain level of abstraction in order to maintain any lasting credibility. But the section on Object-Relational Mapping doesnt even mention that a class of tools exists without the use of EJB CMP (Container Managed Persistence). Thats a real shame, because manually moving data from the object world to the relational world and vice versa is time-consuming and error-prone (and frequently unnecessary) work.
It's a good book, with 285 pages of text and 53 pages of appendices. I've owned it for four days, and I've already managed to steal some of these ideas for the projects I'm working on.
Philip Jacob works for Eyeglasses.com. You can purchase J2EE Design Patterns from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
I call it the tag delimeter pattern.
BSD is designed. Linux is grown. C++ libs
is the buzzword pattern.
Maybe I'm getting old, but at one time we just wrote systems that worked without regard to what was in fashion at the time.
Scottie: Cap'n - I confluckulated and strutified the entity beans, and I'm given 'er all she's got!
...is the spaghetti warehouse with a competence facade. Use it all the time.
I, for one, welcome our new Singleton(); overlord (sorry couldn't resist).
;-)
That should read "I, for one, welcome our Singleton.getInstance() overlord"
Sorry, couldn't resist
The gift of death metal does not smile on the good looking.
>you're never going to be able to account for the wide varieties of situations that occur in the real world with one book full of templates.
Its a pattern, not a final soluton. Use it as a starting point/a headstart.
>Maybe someone can sell this point to me?
Number one reason I like patterns is because it gives me a warm feeling that someone already had to suffer through the same dammed problems as me.
The surprise isn't how often we make bad choices; the surprise is how seldom they defeat us.
Any one notice that our 'new' Singleton overlord is the exact same one as the old one?
TallGreen CMS hosting
If these patterns are truly recurring, why can't I just do something like:
Factory f = new Factory();
Any good programming language should be extensible to handle frequently recurring constructs. Java does not.
That's right, this is a LISP post. We have macros and a whole host of other things you don't, nyah nyah nyah.
Oh yea..LISP is dead. More like, "LISP is a dead end where programmers go to never return to their original language."
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