Struts Kick Start
What is Struts?
Struts is a framework for developing web applications. It is a distilation of the current set of known best practices into a working code set that can be extended to meet almost any web application requirements. It part of the Jakarta Project at the Apache Software Foundation.
What do I know about Struts? I have been developing web applications, using Java, for four years and using struts for over a year, and am a regular participant on the Struts mailing list. I was also a technical reviewer for one of the other Struts Books released this fall and was recently invited to speak at the University of Wisconsin, Eau Claire on the use of Struts.
What's good about this book? There are many excellent things that I could point to. I particularly like the obvious depth of research that accompanies this book. There is a very interesting history of the development of the MVC design pattern and they even name the inventor. Do you know who invented MVC? If you want to know, buy the book! The chapters cover everything that you will need to know, in the order you are most likely to need to know it. There's even a chapter explaining the "struts-config.xml" file's DTD! (You may want to skip that on the first few readings :-)
There is good coverage of the Struts taglibs. I see a lot of questions about these on the mailing lists, so this information is very timely and it looks very well explained.
I like the coverage of other open source tools that work well with Struts. This is an important point because Struts does not do everything for you (by design), so there will be areas that will benefit from other tools. I'm looking forward to trying out some of their recommendations and easing my own Struts development lifecycles.
What's not so good? Just one niggle, and it's more of a programming style issue, but in their example code they have references to their business objects. They explain that it is important to separate out business logic from action logic, which it is, but then proceed to use their business object within the action.
Now, I realise that example code is not the same thing as robust, production-ready code, but when people are first learning a language or framework, they tend to copy exactly what they see in the book they are learning from. Even though example code should be light on error checking, it should be heavy on correctness and good style.
Should you rush out and buy it? If you are about to use Struts on a project, are new to Struts and need dead tree documentation for those RTFM moments or are evaluating Struts for future projects, then you absolutely need this book.
If you are an intermediate Struts user, then this book would still be very useful to you and I can certainly recommend it.
If you are an experienced Struts user, then you've almost certainly exchanged emails with James or Kevin, on the Struts mailing list, so you can make your own mind up!
Table of Contents
- Struts in Context
- The Model-View-Controller Design Pattern
- Hello World!
- HTTP Protocol
- JSP, Taglibs and JSTL
- The Sample Application
- View Components
- The Controller
- Model Components
- The struts-config.xml File
- How the Struts Tag Libraries Work
- Struts HTML Tags
- Struts Bean Tags
- Struts Logic Tags
- The Nested and Template Struts Tag Libraries
- The Struts Tiles Tag Library
- DynaForms and the Validator
- Using Struts with Enterprise Java Beans
- Using Struts with Web Services
- Building, Deploying and Testing Struts Applications
You can purchase Struts Kick Start from bn.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.
Why learn a whole new framwork? A combination of FrontPage and MS Access will do wonders for you - MS Access will even make the VB Code for you after you use the easy drop down utilities to create macros. From there, if you really need more, it is a simple step to port it over to MS SQL Server 2000, which is much, much more enterprise scalable than PostGreSQL or MySQL.
Without Struts, my project at work would be about 100 times more difficult than it already is.
I think Struts has a very bright future...
That's simple man.. Al Gore invented the MVC.
-- jimmycarter
What is Struts?
Struts is a framework for developing web applications. It is a distilation of the current set of known best practices into a working code set that can be extended to meet almost any web application requirements. It part of the Jakarta Project at the Apache Software Foundation.
Struts is a Java/J2EE based framework. Although you could change it to use with other languages, it has taglibs and other features that are pretty much Java only.
Why such an influx of Struts books? Its becoming quite the standard in the Java/JSP+servlet world. J2EE developers are still being hired (hear that unemployed CS people?), and have been strong through the IT drought, and Struts experience is an even bigger plus.
Good quote, too many chars. Seriously, the slashdot 120 char limit sucks!
I still have NO IDEA what struts does. the struts website is not helpful in a brief overview. Saying it helps develop web applications is a joke. What does it replace because I can develop web apps without struts.
Should I be using it? Im too unknowledgeable to even know what question to ask. I use EJB, and I have a webapp. I'm just baffled.
I've been working on a reasonably sized project for some time now (still undercover, so can't go into details)... I'd been looking for a good framework to use, and Struts looked like it fitted the bill.
Until I started dealing with the display (view) side of things.
Getting to grips with the Action and ActionForm stuff is simple, and I think that anyone could do it. However, because they expect you to use all the usual standard stuff (taglibs, etc), building new taglibs and dealing with that was going to be a nightmare.
Also, the HTML taglib, when told to output XHTML only, doesn't work. tags like the BASE tag aren't closed properly.
Fortunately, I'd been looking at using Tea earlier on (Jason Hunter uses it at servlets.com). Someone on the tea mailing list posted a link to a very useful article on using Struts for the backend of a web app and Tea for the front end. You can find it here:
http://www-106.ibm.com/developerworks/library/wa-
http://www-106.ibm.com/developerworks/library/wa-
i thought these were going to replace struts sometime soon...
'Be the change you want to see in the world' - Al Gore
Maybe if we trot out the ol' "Al Gore invented X" meme for a few more years it might get tired, but it sure isn't yet. Hey! I have an idea! Maybe we can even COMBINE CLICHES!
Hahahaha. I'm so clever. And let me just take a moment to make a joke about cigars and interns. And maybe even drop some comment about Vincent Foster, if I'm feeling really bona fide. MMMMMhmm.
Someone there doesn't know how to use it then. The first XML RSS link points to localhost:5335.
Don't get me wrong, Struts is great and I am currently using it in my applications... But, I have to ask, what the big friggin' deal with struts - why all the hype...
.02
Strust is just an implementation of what has already been developed by several companies - I will use Apple as an example. The same sort of thing is done with WebObjects in that the HTML from end and back end Java (or Obj-C) is linked with the need to create any real glue to connect them - it just sort of does it for you - with a nice IDE I might add.
WebObjects (like Struts) allows a developer to connect front end HTML to a server and pass data back and forth so that it's easier to deal with on the server...
Okay so why the rant? Well do you really hear about WebObjects being used all that much, NO! The reason (outside of the fact that when it was a NeXT product it use to cost a forture) it that the learning curve is wicked steep. That is where I see Strust going, it's a great technology, can do all sorts of cool stuff, will ease development but requires some time to get ones head around how it works.
I have seen more than a few projects that claim they use Strust when in fact they use maybe 5% of Strust and still need to use code to glue the front and middle tiers together. It's a real shame that we do not have really nice editor integration - ya ya, I know a few editors have the integration but face it folks, they all suck.
What we need is one of the big guns to step up to the plate and really integrate (and support) struts integration *wink wink* Borland...
Just my
JSF could replace Struts one day, but not for a few years at the least. JSF is still in the early phases, whereas Struts has had several years to mature. I would definately keep an eye on JSF, but wouldn't recommend using it on non-experimental sites for a while.
I like struts and think it is a good step forward, but I have to nit pick. MVC works great in environment where the business logic and functional requirements rarely change. In an environment where requirements change daily and weekly, MVC is a burden on the developers. In those cases a page centric approach is more desireable. If for example your site uses lots of banners and that logic changes rapidly, having it in bean makes life harder than it should. Some one is going to argue, "you didn't do a good enough job generalising it." Sometimes that is a luxury you don't have. How many people have worked in shops where there were no written requirements and requests for changes and new feature are sent every day. Struts borrows some ideas from swing and awt. If your sitaution is one that has an established development process with rigorous requirements stage, then struts should work. If not, look else where.
say it with me now ...
"web-work is monkey-work"
"web-work is not amazing"
"web-work takes a pea sized brain"
i should know - i do web work. because it pays.
because some bunch of fools decided to pay me for
it does not make it clever. because some bunch of
fools decided to pay You for it definitely doesn't
make it clever. step back and look at what you
do and then tell yourself there is anything
remotely complex in there. there isn't. its
crap. its not scottish its crap. quit selling
me books about crap. quit pushing your crap on
everyone else. crap crap crap crap crap.
...and why is Strut kicking it? In other words, why would I even look at a book that can't even get its title right?
It's a overhyped, overcomplicated, manager-type
buzzword compliant "API/framework". It's the
(a)moral equivalent of a 1000 line C++ program
to print "hello world". Those who "get" dynamic
web page creation - don't use struts. It's
a runaway buzzword train and it's a good way
to seperate the wheat from the chaff - if
someone claims to be a "struts programmer", pray
that your competition hires him
...or model/view/controller, was invented by Trygve Reenskaug, and first appeared in Smalltalk at Xerox Parc.
Ok, might be a troll but I'll bite.
Gluh glug...glub.
Rooty poot!
If we don't fight for ourselves no one will.
...or is it that Struts, JavaServer Faces and MVC methodologies merely enforce good coding techniques/styles that one should be using anyway? Regardless of if you are using PHP, Perl, etc.
Or is there something more here?
Sometimes I think Java, OO and other development technologies are like grammer school teachers hovering over our heads saying, "Now, we *know* you are going to be sloppy if left on your own, so are going box you in so that you CAN'T do those sloppy things."
Except that you still can. VERY easy to understand and maintain applications can be coding procedual languages. VERY difficult to understand and maintain applications can be written in OO languages.
But I digress... by nature.
I swear by MacOS X. Although I use to swear *at* MacOS 9...
Hm. I'm not quite sure I follow you here. I haven't read the book, only your review, and I'm a bit puzzled by your statement regarding business objects in actions.
Is it so that the example code for the actions contain business logic directly, or do they use business objects without wrapping them in controllers (like a session bean)
If they're using session beans or controllers in the actions, I can perfectly understand that. You have to use the business logic somewhere.
On my current project, we have a (yuck) flash-client (using macromedia's Flash Remoting MX, btw. nice thing, saves a lot of time usually spent on devicing your own xml-based protocol to communicate with the flash client) . The flash client accesses a standard java class/bean. This bean contains code to massage the output from a session bean to simple data structures more suitable for a flash client (and programmer. Ok, low blow.
The session bean acts as an facade to all the functionality required by/provided to the client (authentication, fetching and updating data etc.) The system has about 10 session beans and quite a few entities.
We've used this approach before, and when we had to add some new types of clients, we only have to add a bean convert to/from client requests and the controller (session bean).
(At first, we only developed a Flash client. Later, we added a SMS client and a web client.)
Struts 1.1 has added nice features like Dynamic Action Forms, integration with JAAS for request level authorization, and separation of functionality through modules.
If you have not previously used Struts this may not mean anything to you. Trust me when I tell you that these advances will be very welcomed by Struts users. I higly reccomend learning Struts, however the existing books only cover previous versions. If you are looking into using Struts on a future project you may want to check out the upcoming release.
Life is like an elevator, sometimes you get the elevator and sometimes you get the shaft.
Actually, what I would like to see is a review of the Ted Husted book Struts in Action , ISBN 1930110502. It was listed as not published yet yesterday at amazon.com, but is now listed as "usually ships in 13 to 14 days." It is available sooner at bn.com or direct from the publisher. Husted is one of the more well-known Struts gurus, and I think his book has been much more anticipated than the one reviewed.
One thing I like is that the publisher, Manning Publications, lets you buy a PDF version of the book for half price. They will also deduct the cost of the PDF version if you decide to buy the tree version later. There are a couple of sample chapters online, one about integration with Tiles and another about validation. The sample chapters I have read seem very complete and well-written.
I know this post sounds like an advert for the book, but I'm not associated with the book in any way. I'm just a Struts developer who's been waiting for a good Struts book to come along, and the Husted book looks like it might be the one.
It's funny because sadly, it's true! Spot on post all 'round. MOD PARENT UP!!
his looks like the abstraction used in asp.net which changes the interaction of web pages to an event based model rather than just posting back forth and checking user values. (correct me if i'm wrong)
it's a big step forward cleaning up web programming. i'm sure it will come to php sooner or later, although i'm happy with old stylee.
...what a thin review. The styrofoam cup is more dense that this. Makes me want to run right out and buy this - not.
XMLC and Barracuda offer a nice alternative to Struts without all the crap of JSP and the enormous clusterf**k single XML file that Struts uses.
XMLC enforces a nice clean seperation of code and presentation data and has a great framework (Barracuda) that does everything Struts does and more. (polymorphic event dispatch and real OO event handling, for example)
Check it out at www.enhydra.org. There's also a great book out on XMLC, if you prefer paper.
I've never used Struts, and my web apps are almost all Perl/CGI, but I'm still curious (of course)..
Would this analogy be reasonably accurate?
Struts : web apps as Cascading Style Sheets : HTML ?
"Truth is not decided by majority vote" consensus gentium -- Norman Geisler
Can anybody help explain the difference, as well as pro's/cons of using XSP vs. Java?
I've been thinking about learning JSP for web development but recently I've started looking at Apache Cocoon which is an XML framework, built on java. It uses XSP to call java business logic which then gets rendered in html. This looks very similar to JSP (except for the XML stuff).
Phrame
I have used Struts, and personally, I really don't see anything special about it. While I agree that having "scriptlets" in your HTML is generally bad form, I have similar problems with putting Java-centric tags in presentation code as well.
Struts, Java Server Faces, Servlets... All of these tools do not solve a real issue at hand, which is that when it comes to internet/HTML applications, the presentation layer should not tie you to any language, or to any language-specific framework.
I should be able to write a "View" that simply Looks at a standard XML-based model, and construct my page from that. Without having to put any kind of Java or Java-based tags in my code. XSLT comes far in doing that, but has a few shortcomings.
The missing piece is a standardized interface upon which posts/gets etc... can be performed without regard to the View, or to the language used in the application server. This interface should of course handle necessary things such as session management, authentication, and the like. This way, we could change out our underlying backend without having to change the presentation code at all.
This is where I give CORBA a lot of props. It definitely had some problems, but it was a wonderful intermediate interface that didn't care who its client was. As long as the client spoke IIOP... life was good.
The same should be done for web interfaces. The presentation layer should not care beans about the backend... expect that the container is aware of a common/neutral interface. No vendor specific tags. No language-specific tags. No proprietary garbage that ties you to any particular container.
XML, XSLT, XSD are great. Java is great. All these technologies are great. But the lack of a common interface/framework which seamlessly ties them together for web applications is the real problem.
We are doing a rewrite of our web application, and have pretty much decided to use struts. However, we can not decide on what to use for object persistance and caching. We have ruled out CMP for performance reasons, BC4J is a option but many of us don't like being tied to Oracle. Are there any open source frameworks for doing this that someone has used successfully and are happy with? Object Relational Bridge? Torque? We could really use some outside input on this.
lame-o
First off, I probably shouldn't have even brought up Tapestry, I'm generating a bad reputation for trying to monopolize discussions and steer them towards Tapestry.
Struts rounds off the rough edges of servlet/JSP development. It does a little streamlining, such as creating an abstraction between actions and JSPs. Actions are subclasses of a struts-provided class and are very, very similar to servlets ... in fact, they must be stateless, just like a servlet.
JSPs are called "forwards" and, in fact, the plumbing doesn't require that the output be JSPs, you can plug in other templating systems such as Velocity.
There's standard taglibs that help with creating URLs that reference actions, help with building forms, and there's a system, called form beans, where query parameters are picked up and dumped in as properties of a bean, which is then passed to an action for processing.
That's really about it.
Tapestry is simply a different kind of beast. It's goals are different ... it doesn't round out the edges of the servlet API ... it makes the servlet API irrlevant to the developer. You create Tapestry applications without thinking about URLs, query parameters or any of that jazz. It's all "objects, methods and properties".
Let's take a simple form example. In Struts you would have to
Struts doesn't have any kind of namespace management, so if you are on a a big team, you have to be careful to name things uniquely.
In Tapestry, you would
Although this looks similar, its much easier in Tapestry. Everything you need to do is localized in the three resources of the page (the specification, the template or the class). You write very, very little code ... instead, you declare what you want the framework to do inside the page specification (an XML document), or even inside the HTML template (more like taglibs, and a 2.4 feature in progress right now).
These page specification entries are pretty short, for example:
This says "use a TextField component, bind its value parameter to the name property of the employee property of the page". This assumes that your page class provides a JavaBeans property, "employee". The accessor method knows how to obtain this object from a backend database or EJB.
You and the other developers aren't conflicting on access to struts_config.xml. No change that another developer makes to thier page will break yours. Name conflicts simply can't happen ... each page is like a little application unto itself.
In both frameworks you have to provide the business object to the form. In Struts, an action has to store a bean as a HttpServletRequest. In Tapestry, the page provides an accessor method that exposes the business objects to the components on the page.
Tapestry does much more work for you when the form is submitted. Notice that you don't specify a URL, action, page or anything with a Form component, you simply tell the Form component what method to invoke when the form is submitted.
The form components will pull request parameters, convert the parameters to correct Java types, and apply changes to the properties of the business object. If you are using the validating text field component, then more conversions and validations occur, automatically (and properties are only updated if the input is valid).
Once all the properties have been set, the Form will invoke the listener method which carries things forward from there, including selecting which page will render the response.
On something like a login page (i.e., user name and password), you don't need a seperate business object; your form components can simply update corresponding properties of the page object itself.
Right there is one of the big differences; the objects Tapestry users work on are stateful, not stateless. You don't have to deal with that problematic indirection (storing everything as request or session attributes). Tapestry does the shuffling of data to and from the session for you, invisibly. It uses object pooling so that you code naturally (objects with methods and properties) without worrying about multi-threading issues.
Now, that's just off the top of my head and doesn't scratch the surface of what Tapestry can do. The important thing is that its all about components, and creating new components (and even packaging them into libraries of components) is a snap, in fact its often a necessary and natural part of creating an application.
Unlike taglibs, Tapestry components can (and usually do), have their own templates and often are constructed from other components. Very natural, much more like a Swing GUI in terms of composition.
Because all of the request dispatching is performed by the framework (both during render, when the framework creates URLs, and in subsequent requests, when the framework interprets those same URLs), components can have thier own private listeners and behaviors.
Thus you can have things like MindBridge's Table component, that has sortable column headings. The links for the headings are components embedded within the Table component, and the Table component provides the listeners for those links. You can have ten Table components on ten different pages, or ten on the same page and everything just works, no questions asked.
Everything in Tapestry is designed to assist the developer ... wringing more functionality out of less effort. When things go wrong, it has incredible exception reporting.
Right now we're working on release 2.4 which includes significant improvements that will make Tapestry the easiest (and still, most powerful) web app framework available.
There's reams of documentation at the Tapestry Home Page and you might just want to check it out (if you want something more coherent).
Howard M. Lewis Ship -- Independent J2EE / Open-Source Java Consultant -- Creator, Apache Tapestry and HiveMind
Here's what I don't understand - what jakarta technologies are mutually exclusive with each other? I did apache jserv development for a couple of years and I want to update by using java for a large scale personal project. My brain is tumbling around several options:
1) struts
2) tomcat/jetty
3) EJB (jboss/resin)
4) enhydra
So, what can be used with what? Can #1-#3 be all used together? I mostly just want to gain wide experience to help the old resume.
skkkoooonnnggggkkk ptui
Thank a lot dude, I wanted to find out in the book
Of course, MS SQL is actualy more scaleable then MySQL, but that's beside the point :P
autopr0n is like, down and stuff.
The problem with web development in java is two fold. It is slow and not a very productive environment. PHP, NET and Perl will always be more productive. Now the PHP ported struts framework, now we are talking.
Got Code?
Thanks to AC for the pointer to the Struts in Action review, I don't know how I missed that one. I put in a link, since your URL got munged by the Slashcode...
And, thanks to James Turner for the heads-up about Safari and the sample chapter over at strutskickstart.com. I'll check it out right away. Good luck with the book, it looks like it is getting a lot of good reviews so far.
It was built using Userland Radio, and we haven't set up the RSS channels yet. I've been busy helping with the 1.1b3 Struts release... James
really, enhydra is just awful. Too bad you wasted time writing it.
http://sf.net/projects/tapestry
This is *much* nicer than struts/JSP. It makes producing reuseable components much easier, and abstracts servlets very nicely, while still allowing access to the bare meal if needed. And it has the best documentation of any OSS project I've seen!
Tom
I have discovered a wonderful
As someone who has recently moved over to Java from other languages, Struts has really helped me understand MVC and the power of XML to control large applications. Servlets are extrememly powerful and robust and very handy to be controlled from one line of code in the config.xml... If you want to see some of cooler things you can do with struts, check out keyboardmonkey's site- servlet tree hierarchy... very handy.
For all those who have never tried out the struts framework- give it a chance... and you don't need a $50 book to try it out. Try out Ted's Tutorials and learn through example!
www.startvino.com