Struts Kick Start

Simon P. Chappell writes "I started learning how to use the Struts framework in late in 2001, after I became fed-up with hacking web applications together with the digital equivalent of "Duct-tape Engineering". At that time there were no books available for the budding Struts developer, "Read The Fine Manual" was not an option ... you read the website, you read the code or you asked questions on the mailing list. This situation finally changed this fall with the release of a flurry of titles dedicated to Struts. I present here my thoughts on one of the latest: "Struts Kick Start". The rest of Simon's review follows. Struts Kick Start author James Turner and Kevin Bedell pages 481 (29 page index) publisher Sams rating 9 reviewer Simon P. Chappell ISBN 0672324725 summary You need this book

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

1. Struts in Context
2. The Model-View-Controller Design Pattern
3. Hello World!
4. HTTP Protocol
5. JSP, Taglibs and JSTL
6. The Sample Application
7. View Components
8. The Controller
9. Model Components
10. The struts-config.xml File
11. How the Struts Tag Libraries Work
12. Struts HTML Tags
13. Struts Bean Tags
14. Struts Logic Tags
15. The Nested and Template Struts Tag Libraries
16. The Struts Tiles Tag Library
17. DynaForms and the Validator
18. Using Struts with Enterprise Java Beans
19. Using Struts with Web Services
20. 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.

Comments

Struts?

[Anonymous Coward]

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.

Re:Struts?

[MaxwellStreet]

hehe . . .

Not sure if this is a troll, or intended to be funny . . . but it works on both levels I suppose.

Anyhow, I've been using Struts for about a month refactoring a largish internal Oracle PL/SQL web app, and the MVC separation that's enforced by the Struts framework is really just what the doctor ordered. I'm getting similar functionality in roughly 20% of the comparable lines of code; and this is early enough in the project to where code reuse hasn't even come into play much. I'd imagine it'll end up at about 15% - i.e., 150K LOC using struts as opposed to about a million LOC using PL/SQL.

I know Lines of Code isn't necessarily a good measure of just about anything - but the real benefit is maintainability and ease of expansion (which is what brought on this refactoring to begin with).

Struts is really worth a long hard look - gets you away from using the technologies above and into a real enterprise-class web application structure.

MVC

[jimmyCarter]

That's simple man.. Al Gore invented the MVC.

Re:MVC

[ErikZ]

You see, the problem is that no one cares. It's a funny story that doesn't really hurt anyone. Pointing out that it's technically wrong is like watching a movie and pointing out things that are impossible.

It's just annoying.

Re:MVC

[Malcontent]

"It's a funny story that doesn't really hurt anyone."

Well it probably hurts him. It also probably hurts his family. It may well have cost him the election (it was a close one after all) and as a consequence has hurt lots and lots of people. Maybe, just maybe there would be less dead people in the world if that lie was not so widely circulated.

Even if it did not hurt anybody then it's still a lie and should be corrected whenever possible.

Re:MVC

[ErikZ]

And maybe we would all be dead if he was, "What if" scenerios are endless.

I doubt it hurts his family...at all.

It may have cost him the election? It may have gotten him votes. After all, if he invented the Internet, he must be a pretty smart guy.

You don't like to see your canidate look stupid. That's understandable. Let me know when you start protesting when people go "George Dubya Bush".

Re:MVC

[Malcontent]

"I doubt it hurts his family...at all."

And you know this how?

"It may have cost him the election? It may have gotten him votes. After all, if he invented the Internet, he must be a pretty smart guy."

Which scenario is more likely?

"You don't like to see your canidate look stupid. That's understandable. Let me know when you start protesting when people go "George Dubya Bush"."

He himself pronounces it dubya. What you want me to do correct him?

Re:MVC

[ErikZ]

"And you know this how?"

The same way you know that it "Probably hurts his family." Don't apply levels of proof to me that you are not willing to apply to yourself.

"Which scenario is more likely?"

Nobody knows.

"He himself pronounces it dubya. What you want me to do correct him?"

I was going to respond to that question phonetically, but that requires too much effort and I doubt you'd get the point.

Re:MVC

[Malcontent]

"Which scenario is more likely?"

Nobody knows.

----

Just goes to show how idiologically rigid people are incapable of coming to any conclusion which may conflict with their religious beliefs.

The rebuclicans invented the lie and propagated it to HURT him both personally and in the election. In fact I saw John Sununu repeat that lie on tv (hardball IIRC) and follow it with the phrase "not only is Al Gore a liar he is a stupid liar".

How can you possibly think that propagating this lie over and over by prominent republicans and the republican media had an indeterminate effect. Rush Limbaugh, Bill Oreilly, Fox TV, CNBC and the wall street journal wield incredible power, certainly enough to make a less then one percent difference in a close election.

Re:MVC

[ErikZ]

Or...

Two groups of people who are ideologically opposed to each other will pick up anything that sounds true, as long as it trashes the other side.

"Sir! Did you hear that Al Gore is claiming that he invented the internet?"
'What? Did he?'
"No! I was invented by the military!"
'Ha! We got him on that one! Start running the presses!'

"Just goes to show how ideologically rigid people are incapable of coming to any conclusion which may conflict with their religious beliefs."

Ok, now you're just trolling. What does a person's religious beliefs have to do with this?

Re:MVC

[Malcontent]

"Two groups of people who are ideologically opposed to each other will pick up anything that sounds true, as long as it trashes the other side."

I don't dispute this. What I dispute is your contention that continually lying to the public by the republican party about what Al Gore said has either

a) Had no effect on the election
b) Had a beneficial effect for Al Gore in the election.

You claimed both of these because you can not admit that a continual repeating of this lie could have made a difference in the outcome of the election (and therefore making profound difference in the world).

Not only that but you are incapable of admitting that lying about somebody is probably hurtful to them and their family.

Because of the rigidity introduced into your thinking process by strict adherence to an idiology your mind is incapable of coming to conclusions which may cause dissonance with that idology or point out that the idiology (and the idiological leaders) may end up using sleazy means to achieve their ends.

You insist that that it was a "harmless lie" and that it did not "hurt anybody". Any logical person would have to conclude that it was not a harmless lie because in a close election there is a high probability that it had an effect on the election and that it not only hurt Gore family but because of it's effect on the election it hurt all democrats.

Of course I can't see a Gore presidency being so indefferent to the plight of the palestenians and declaring a war on Iraq so you could theoretically add the upcoming deaths of tens of thousands of iraquis to the list of people hurt by that "harmless lie".

Re:MVC

[ErikZ]

"You claimed both of these because you can not admit that a continual repeating of this lie could have made a difference in the outcome of the election (and therefore making profound difference in the world)."

Actually, I can't believe that the continual repeating of a stupid joke would make a difference in the outcome of an election. Considering that Gore didn't do anything to make sure that voting machine fiasco didn't happen again, makes me think that he didn't care either.

"Not only that but you are incapable of admitting that lying about somebody is probably hurtful to them and their family."

Lies are part of politics. If this one stupid joke wreaks havoc on the Gore family, then they're dead meat when the professional lies and spin comes along.

"You insist that that it was a "harmless lie" and that it did not "hurt anybody". Any logical person would have to conclude that it was not a harmless lie because in a close election there is a high probability that it had an effect on the election and that it not only hurt Gore family but because of it's effect on the election it hurt all democrats."

Any logical person would like a bit more proof than "You think it sounds right." Normally, I'd be happy to chew on that concept with you. Except that when I put forth my theory, you suddenly wanted proof. So fine, if you want to be like that, bring me proof that it had an effect on the election. You have NO IDEA what people use as a criteria for voting, and giving the impression that you know what they do is a lie.

"Of course I can't see a Gore presidency being so indifferent to the plight of the Palestinians and declaring a war on Iraq so you could theoretically add the upcoming deaths of tens of thousands of iraquis to the list of people hurt by that "harmless lie"."

The Palestinians have been in this "Plight" for how long? 30 years? And despite the constant aid from many western nations and the UN, they have barely improved. Maybe trying something different, like Bush is doing, is the key to fixing the problems. You're right though, Gore probably would of continued to push the same policies that don't work, causing no improvement in the situation. What bold leadership!

As to the "Tens of Thousands" that will die in Iraq from the future attack. Is that the total, or the people that Sadamm takes down with him as he invades? It's probably just a rumor that he's been planting chemical bombs in his own cities for the US invasion. After all, he wouldn't kill his own people, would he?

But I'm glad you're here to stick up for Tyranny. That no matter how bad other people have it, or how much our interests are threatened, you're here to let us know that we shouldn't do anything to solve it, if it involves people dying.

Re:MVC

[Malcontent]

"Actually, I can't believe that the continual repeating of a stupid joke would make a difference in the outcome of an election."

Once again this is due to your idioogical inflexibility. The race was decided by a few hundred votes. It is reasonably probable that repeatedly lying about Al Gore would have influenced a few hundred people (which represents a minute percentage of the voting population).

"Considering that Gore didn't do anything to make sure that voting machine fiasco didn't happen again, makes me think that he didn't care either."

He had no power to effect any change. If he had become the president then he would have had the power to do somthing about it. As a private citizen there was very little he could do. There was a class action suit in florida about denying black people the vote by wiping them off the rolls as felons and florida paid a bunch of money to a bunch of folks. As far as I know that was only real consequence for rigging the election.

"Lies are part of politics. If this one stupid joke wreaks havoc on the Gore family, then they're dead meat when the professional lies and spin comes along."

I did not say that it "wreaked havoc" I only said that it hurt them. Again your idiological inflexilibity prevents you from admitting what most people understand very well. Telling lies about people hurts them, making fun of people hurts them. Maybe like you say it's OK to hurt people a little or maybe it's OK to hurt Al Gore a little, maybe it's ok to hurt people as much as possible but not enough to "wreak havoc" with them. I really don't know where you are coming from in this regard. Even if you think it's OK to hurt Al Gore by lying about it (despite what the ten commandments says about bearing false witness) at least admit that it did most probably did hurt him.

"The Palestinians have been in this "Plight" for how long? 30 years? And despite the constant aid from many western nations and the UN, they have barely improved. Maybe trying something different, like Bush is doing, is the key to fixing the problems."

Well I don't want to get into a detail discussion about the plight of the palestenians here but I don't think anybody would agree that they are better off under a bush presidency then they were under any other administration. You are right for the last 30 years they have been suffering miserably under a military occupation by Israel but only in the last couple of years has that been compounded by widespread malnutrition and starvation.

"You're right though, Gore probably would of continued to push the same policies that don't work, causing no improvement in the situation. What bold leadership!"

IT might not have improved the situation but then again I bet most palestenians would have prefered their previous miserable conditions to their present event more miserable conditions. Sometimes staying where you are is better then losing ground.

"As to the "Tens of Thousands" that will die in Iraq from the future attack. Is that the total, or the people that Sadamm takes down with him as he invades?"

I am only counting the deaths that will be caused by our own bombing. Last time we attacked them we killed over 50,000 people and of course more died as a result of our destruction of crucial infrastructure such as electricy generation facilities, water treatment plants, roads and bridges and such. We also killed something like 30,000 people in afghanistan. I am presuming that we will kill at least 10,000 people in Iraq which is a very conservative estimate. Saddam might also kill some people while retreating or as a scortched earth last defense type of situation. Either way it's totally unnecessary. If we decided not to invade both types of deaths could be avoided. This war with iraq is very avoidable.

"It's probably just a rumor that he's been planting chemical bombs in his own cities for the US invasion. After all, he wouldn't kill his own people, would he?"

If we did not invade then he would have no need to deploy those weapons.

"But I'm glad you're here to stick up for Tyranny."

I am doing no such thing. Try another line of attack if you want to. Lying is not an effective argument method. You can not simply try to demonize whoever you are arguing with and make yourself right. The truth does not work that way.

"That no matter how bad other people have it, or how much our interests are threatened, you're here to let us know that we shouldn't do anything to solve it, if it involves people dying."

What a fine sentiment except that it's a non sequitor. We have no interests there except oil and I for one believe that's it's wrong to kill people and take their stuff even if that stuff is oil. You apparently also think the only way to solve whatever problem you perceive is by killing lots of iraquis and militarily occupying their country. I for one believe that there are many many other options. Any solution to whatever problem you perceive has to make the situation better for the people who "have it bad".

State the problem, consider the available options and choose the one with causes the least amount of harm. So far I have not even heard what the problem actually is.

If it is weapons of mass destruction then we should deal with it like we deal with other countries that have weapons of mass destruction.

If the iraqui people are suffering (and they are) then let's try to help them.

I have also heard people point out that Saddam has killed his own people (well they were kurds and he does not view them as his own people but that's beside the point). The fact is however that the US govt had no objection to that when it happened and it's a bit silly to have any objection to it now that's too late. In fact we gave him the knowhow and the technology to do that in the first place. What he did was evil and it should have been dealt with then.

Re:MVC

[ErikZ]

"Once again this is due to your ideological inflexibility."

Out of curiosity, what brand of ideology do I subscribe to? I'm just curious as to where you've pigeonholed me.

"He had no power to effect any change. If he had become the president then he would have had the power to do something about it. As a private citizen there was very little he could do."

Interesting. I was told that when Nixon lost the presidential election to Kennedy in Chicago due to voter fraud, he was furious. And then he fixed the system so it couldn't happen again. So, either I was lied to or you're wrong.

"Telling lies about people hurts them; making fun of people hurts them."

You ate 38 jelly beans for breakfast.
Your momma is so fat; when she ran away she took up all four sides of the milk carton.
Bill Clinton dyed his hair bright purple and joined a heavy metal band.

All three statements above are a lie. Are you hurt? Is your mother hurt? Is Bill Clinton hurt?

No.

"Well I don't want to get into a detail discussion about the plight of the Palestinians here..."

Seriously? Then don't bring up such a hot topic. It forces me to address it with a rebuttal. Otherwise it looks like I'm conceding your point.

"
I am only counting the deaths that will be caused by our own bombing. Last time we attacked them we killed over 50,000 people and of course more died as a result of our destruction of crucial infrastructure such as electric generation facilities, water treatment plants, roads and bridges and such. We also killed something like 30,000 people in Afghanistan. I am presuming that we will kill at least 10,000 people in Iraq which is a very conservative estimate. "

I've had a VERY hard time getting consistent numbers about the gulf war. Civilian deaths have gone from 30k a WEEK during the war to less than a thousand for the whole war. But I find it hard to believe that we directly bombed civilians to the tune of 30k deaths. The sheer amount of effort and ammo required to kill that many people would not go unnoticed.

"If we did not invade then he would have no need to deploy those weapons."

And this is the most ridiculous statement you've made so far. Not even Hitler came up with the idea of killing his own people as a deterrent against invasion. It's monstrous if true and would be reason enough to depose the rulers of Iraq.

At what point do you think it's appropriate to invade another country?

"I am doing no such thing. Try another line of attack if you want to. Lying is not an effective argument method."

Excuse me? Your agreements show that you don't believe in invading Iraq. Currently Iraq is ruled by a cruel dictator. There is only ONE way to improve that country and it's to remove it by force. Any argument to the contrary, even "Well, if Al Gore was president, we wouldn't be invading." is saying that you prefer Sadamm to be in power. Sounds like sticking up for tyranny to me.

"We have no interests there except oil and I for one believe that's it's wrong to kill people and take their stuff even if that stuff is oil."

Lying is not an effective argument method.

"State the problem, consider the available options and choose the one with causes the least amount of harm. So far I have not even heard what the problem actually is."

Seriously? We've fought a war, committed sanctions, and conducted inspections, and enforced no-fly zones and you STILL don't know what the problem is? A big help is to imagine yourself as the leader of the U.S. and withdrawing from Iraq without doing anything. Imagine the ramifications.

"The fact is however that the US govt had no objection to that when it happened and it's a bit silly to have any objection to it now that's too late."

Er, the US didn't have a problem with that. You are who has the problem with civilian causalities(From the Gulf War). And when I pointed out that Sadamm is willing to kill his own people, you switch to the line of argument "Well; now the US can't say anything about Sadamm killing his own people because they didn't say anything when it happened before. And now it's too late."

So, back to where we started from. Gore didn't invent the internet, but it's a cute joke. You say it effected the elections in Florida. I say that the amount of people who voted for Bush because of this, were canceled out by the people who voted for Gore because they liked the color of his tie.

How many people stayed home and didn't go out and vote because they heard that the exit polls on the news telling them that Gore won? I must admit, I wish they did the whole thing over again. The margin of victory was too small for me.

Little nitpick

[FortKnox]

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.

Re:Little nitpick

[bataras]

Struts is NOT J2EE based. it's plain vanilla JSP/Servlets based

Re:Little nitpick

[rutledjw]

I wouldn't call it easy, but Denver has been it hard. Having 3+ years and knowing what the f*ck you're talking about in an interview does help out.

I point out the latter as I've interviewed a LOT of people and I've seen lots of great resumes with Java exp and owners of those resumes who look at you blankly when you ask any degree of difficult question...

No idea what it does

[dnoyeb]

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.

Re:No idea what it does

[revscat]

Struts is an MVC-based framework for developing web apps. It helps to separate out the different layers of your application. You could use it with EJBs, if you wish, because it is mostly a means for separating out your business logic from your presentation.

Asking "should I be using it?" is difficult to answer, because it depends upon your requirements. But if you are developing a web application that requires a quick turnaround time and is easy to maintain, Struts will help you along.

Re:No idea what it does

[Boss, Pointy Haired]

It replaces the tedium of having to write your own form handlers, IO verification and output generation with the tedium of having to learn Struts.

Re:No idea what it does

[Malcontent]

Oh man that's funny as hell.

Re:No idea what it does

[revscat]

I thought we already had MVC with JSP/servlet/EJB. How does Struts change this? From what I can tell it's some sort of framework that handles form data validation. That's always rather tedious, so if Struts saves time it's a good deal.

Mmmm.... Part of Struts is validation, although technically it is a separate component. (See the Jakarta Commons Validator) This is a minor (though extremely useful) part of it, however.

What makes Struts what it is are (arguably) ActionForms (basically, JavaBeans with some enhanced functionality) and ActionForwards/ActionMappings. These allow you to separate out the logic which operates upon data which will eventually be diplayed from the actual display of that data. Because solutions which depend upon JSPs tend to become a mass of unreusable scriplets, having this separation allows for a more maintainable site and avoids the pitfalls which have traditionally plagued JSPs.

Re:No idea what it does

[rutledjw]

Yeah, but it's a framework you fool! Is it possible to develop without a framework/methodology/pattern/architecture/tool?!?

Mmmm, kool-aid...

Re:No idea what it does

[autopr0n]

if there's any bored document writers out there... jakarta and apache really need your donations! any corporations needing an extra tax write off? please donate a doc-writer to these projects.

I KNOW! Apache seems to make so much usefull stuff, but they never explain what it does! I like nice names as much as the next guy, but apache has so many projects it would really be helpfull if they picked more descriptive ones, I.E. "Apache JSP/Servlet server" rather then "Apache Tomcat".

Struts is great, but...

[General_Corto]

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-t ea1/

http://www-106.ibm.com/developerworks/library/wa-t ea2/

Re:Struts is great, but...

[MaxwellStreet]

Velocity is another jakarta project that helps out on the view side of things. You might want to check it out . . .

java server faces

[rhyd]

i thought these were going to replace struts sometime soon...

Not for a while

[revscat]

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.

ok folks

[Anonymous Coward]

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.

Re:ok folks

[fraxas]

The majority of web-work -- as you put it -- is crap.

Lucky for us, most of web application development isn't web work -- it's application development. So we're not so crapful after all.

MVC...

[blamanj]

...or model/view/controller, was invented by Trygve Reenskaug, and first appeared in Smalltalk at Xerox Parc.

Is it just me...?

[Malic]

...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.

Re:Is it just me...?

[revscat]

...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.

Yes. That is indeed largely their purpose. I don't see how that's a bad thing given that you almost always develop with people who have varying degrees of discipline when it comes to sticking with good coding practices. Some (like me, honestly) are damn near fanatical when it comes to sticking to plan. Others don't care as much, so long as the job gets done.

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.

I think that both cases depend upon the quality of the code(r), and what you personally prefer. I tend to find OO solutions more elegant and easier to maintain, whereas it has been my experience that with functional languages it is dangerously easy to wind up with an unmaintainable and barely understandable mass of spaghetti code. This is especially true whenever time begins to run out and deadlines approach: people freak out and start slapping out code that they would normally be embarrased about. Having a structure like Struts in place helps to keep this from happening.

This is not to say, of course, that people don't make classes that are nothing more than a series of

public static final

methods, and that wind up behaving exactly like the procedural languages. In any language worth it's salt it will be possible to code both well and badly.

What's not so good?

[Brummund]

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.

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.)

looks like the abstration in asp.net

[xdrone]

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.

Re:looks like the abstration in asp.net

[joib]

I'm no php man, but I hear that phrame is a struts clone for php.

If you're not committed yet, check out XMLC.

[brad.hill]

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.

similar to CSS?

[miltimj]

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 ?

Re:similar to CSS?

[Phoukka]

Err, no. Or, not really. Or maybe, just not quite. You see, on one level, CSS is used to separate presentation from HTML, leaving structure & semantic meaning only in the HTML code. Struts is used to enforce separation of business logic from presentation logic. So, at a really REALLY high level, they do similar things. But the analogy dissolves as soon as you get to even 50000'.

With Perl/CGI + (X)HTML + CSS, you very likely are coding in a procedural style (feel free to correct me if I'm wrong -- or, just don't take it personally, let me explain the idea) in your CGI script. With Struts + (Tomcat or other servlet container) + JSP + HTML + CSS, well, things get more complicated -- yet easier to code and maintain.

With just Tomcat + JSP, you can code up a servlet, the Java equivalent of /successor to a CGI script, and that one servlet will handle all input, all business logic, and all output. But this style of coding is generally considered bad, because it is much more complex than it should be -- it hinders maintenance, updates, performance, clarity, etc. Java, being object-oriented, allows the programmer to separate business logic from web app control flow from presentation. However, it doesn't enforce it. And that separation is not necessarily easy, it requires discipline and creates more work if the coder starts from scratch. Which is where Struts comes in to play. Struts is a framework of Java code that works with Tomcat (or other servlet container), that enforces separation of business logic from control from presentation, and provides lots and lots of goodies that make it much much easier to code the application.

So, if you have an application that isn't throw-away, one that will need to be maintained and possibly changed later, Struts makes building the application easier because it keeps unrelated parts from bumping into each other, and has lots of pre-fabbed goodies.

Re:What the big deal with Struts...

[richieb]

The learning curve can be a bit steep, but not as steep as Struts in many ways (I use Struts at my current job, and it was a massive pain for me to shift gears and work within the limitations of Struts).

So how about a quick comparison of Tapestry and Struts? What's easy to do with Tapestry that's hard with Struts?

Struts ported to PHP

[tetranz]

Phrame

Re:Show the full respect of Struts...

[mr.buddylee]

I personnally think Struts makes things harder. I haven't gotten into it a lot, but it seems to take me a whole lot longer to get a project done with struts than if I just used scriplet code. The only reason I use it is because I have to, I sure wouldn't us it if I had a choice. It's limiting in what you can do, and the ways you can do it, there was little to no documentation (until now I suppose), and it's just confusing. I'll admit that I'm a novice JAVA programmer, but seriously, why use a tool that makes things more difficult. It's just a tool to use until the next big thing is pushed out by a group of programmers with too much time on their hands.

Just more retreading on the same tire...

[javabandit]

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.

Re:Struts is GARBAGE

[Lysol]

Not true at all. I've been following Struts for a *long* time and depending on the project it can make a huge difference. Sure, you can code page to page, embed the logic wherever and move on your merry way. But adverse things will definitely start to happen when:

1. you are no longer 'the man' and the mgmt rolls in the html guy(s)/gal(s). most html people can deal with <xml style markup> than <%java scriptlet%> stlye <%blocks%> (i won't even get into logic flow in scriptlet blocks). separation of presentation logic from biz logic; speaks for itself. and it's possible with scripting languages, but tough.

2. you want to extend the app. 'oh, but marketing want's to have their server also come in on that url that you did last year'. true, you could accomplish extension well with scripting language, but the delegation with struts/MVC us much cleaner and more maintainable.

3. you want to debug/qa. struts is tested and kid approved. i'm going thru something right now where our system has bugs and no one really knows cuz different people have worked on each others code and did everything differently. and even on a huge project in the past i had done, it was still hard for me to figure out flows and such when they were scripted from page to page. a unified framework helps resolve those differences in coding and thusly, easier to debug.

And I'm sure there's even more things that I haven't listed. One issue to really consider is do you want a page to page thing - which is good for proof of concept, quick and dirty. Or do you want something you can live with for the next year or so? Using a framework like struts will make your long term much easier.

For the biggest project I worked on, a major airline portal, we rolled our own MVC framework. This was prior to struts and yet in the end, the code was very similar. Their system runs on over 100 Sun CPUs and has been cranking away since they launched a few years back, without a major crash or anything.

This stuff does work and the bigger the project, the better. It's a little tough to get in the beginning, but after you implement it, you start to see that it makes sense. I feel tho, it's definitely more of an 'enterprise' thing than a small 20 page site; altho, u could use it for a small site if you wanted, no problem.

Re:Show the full respect of Struts...

[rutledjw]

No, no, no. As you get going in Java you'll be the logic in it. As a novice programmer, it SHOULD take you a lot longer to use a tool like struts than use (whatever). You're still getting used to the syntax, flow and appropriate use of Java.

As you get going, there becomes a more elegant technique to using teh language. Tools like struts fill the need.

Learn what you can now and don't worry about it, the usefullness of struts will become evident as you progress.

Re:Show the full respect of Struts...

[CorwinOfAmber]

I haven't gotten into it a lot, but it seems to take me a whole lot longer to get a project done with struts than if I just used scriplet code.

Well of course it's going to be faster and easier (for you) to just put all of the code in scriptlets. But I sure wouldn't want to have to maintain your code. You don't separate your business logic from your display code because it's faster to develop it; you separate your code to make it easier to maintain, and more robust. Writing maintainable code is always going to be a bit more work in the short term, but it pays off over the long term.

which java where?

[tunesmith]

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.

Re:which java where?

[ChannelX]

Enhydra is an app server. they have supporting APIs to create web apps (XMLC for one...I think Resin might support it as well). Resin is a jsp/servlet engine. There is an addon for EJB. tomcat and jetty are also jsp/servlet engines. Struts is an API for doing JSP/servlet development. It uses jsp/servlets. JBoss is an EJB container. It would work in conjuction with jetty/tomcat/resin. Lots of the apache jakarta projects work with each other. That makes them somewhat confusing at times but it really is pretty cool.

Re:which java where?

[Tom Davies]

1. Struts is a framework for writing web applications based on JSPs and servlets (Tapestry -- http://sf.net/projects/tapestry is way better) Struts (and Tapestry) can be used with any servlet engine.

2. Tomcat and Jetty are servlet engines.

3. EJBs are used for writing applications which *need* to be distributed or need to be buzzword compliant.

4. dunno

Tom

Heh

[autopr0n]

Of course, MS SQL is actualy more scaleable then MySQL, but that's beside the point :P

The problem with web development in java

[codepunk]

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.

Re:The problem with web development in java

[ChannelX]

I see you have never used Java and have absolutely no clue what you're talking about. Java is not slow. It is not slow on the server. It is not slow on the client. JSP/Servlets/EJB with or without Struts, etc are as productive as PHP, .NET and Perl. There are tons of options out there for doing web-based development in Java.

Re:Tapestry and Struts

[richieb]

Thanks for a great answer. I'm already familiar with Struts, I'll have to try Tapestry...

Try Tapestry

[Tom Davies]

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