I am going to teach myself some Java EE and making a simple web portal where people can generate their own invoices(pdf lib is needed). Not asking about any code but can you give advice (examples) which technologies I can make use of through the process? I have decided to use "Spring MVC" as the framework + java/Kotlin as a compiler. Some database + server + email+ some micro services?, are needed but which can it be? Thank you!
If you are trying to implement microservices, i prefer spring boot which has embedded tomcat with additional services, and for database you can use open source mysql
if you are also planning for UI stuff and new to it prefer basic Html,css and Bootstrap
If I am there here are my choices. All these choices are based on my past 4 complete end to end web application project experience.
Spring Boot
Using spring boot create micro services. As it has in built tomcat it will be easy to deploy any environment, either local laptop or on premise server or cloud server.
JPA with Hibernate
If you are looking for free you can choose MYSQL. As it has strong community support
almost all the issues you are going to face would have been asked and answered already under stack overflow or somewhere else in the internet. Another think is as you chose JPA you can switch to any database easily.
React
As of now the simplest and one of the fastest ui framework. Also it has strong user support. You can find answer to almost all questions you will have on internet.
Apart from all, you can extend any of these technologies. Happy Coding!!!
You may want to consider using Jaspersoft for generating your pdf files:
https://www.jaspersoft.com/reporting-software
https://community.jaspersoft.com/wiki/introduction-jaspersoft-studio
There may undoubtedly be other solutions out there, but this is the one I'm most used to.
Related
Lagom by default uses Google Guice as implementation od DI pattern.
I would like to use Spring Framework instead.
Is it possible? IF so, how should it be done?
I have successfully integrated Akka with Spring (using hints from documentation and Internet), however I cannot find anything in documentation about integrating with Spring.
Possible? Yes. Will you be constantly swimming upstream, with reach upgrade break in new and unexpected ways requiring you to debug undocumented internal APIs? Most probably.
Lagom is built on Play, Play's DI support is ostensibly pluggable, when I wrote it I hacked together a proof of concept to ensure that Spring could be plugged into it. But it was only ever a proof of concept, neither I or the Play team ever had any desire or intention of maintaining it, so I published my work to GitHub:
https://github.com/jroper/play-spring
So that anyone for whom Spring support was important could continue where I left off. That was 3 years ago. In spite of a community of over a hundred thousand developers, no one ever took the work up. There's not a lot of work to do on the module itself, where most of the work would be is in Play and Lagom to fix areas where they have grown incompatible with Spring.
But really, why do you want to use Spring? The whole Lagom and Play ecosystems are built on Guice, saying you want to use Spring with Lagom is like saying you want to use a narrow gauge train in a country that only has standard guage rails, you're going to have to build yourself an entire new rail system to do so. What do you hope to achieve?
I was thrown into a CXF-based project in which the basic HowTo tutorials are easy to follow and implement but the moment there is a problem or a bug in the system, all kinds of exceptions are thrown without me understanding any of the relationship between the various components.
I know that CXF builds on top of Spring.
But I have no experience with Spring and I don't know how it works.
I have also seen references to JAXWS in the cxf.xml but I don't know how it is related to either Spring or CXF.
I can build a perfectly working (simple) CXF-based web service. Contract first, using wsdl2java in a pom.xml (copycatting a sample).
But the moment I face a problem, I am stumped, relying on some tips and clues gleaned from the web.
Ideally, I would like to have a tutorial that walks me through the history of how web services evolved from Java only, to J2EE, to JAXWS, to Spring, to CXF.
But I couldn't find any.
I did find the official Apache CXF documentation but it assumes a lot of prior knowledge that is more than just knowing the Java language.
Any recommendations on how to get to a point of truly understanding what I am doing when I build a web service?
A recommended book? Online tutorial?
Thanks.
Yip it is a bit of a learning curve but well worth it. As far as books are concerned you can try the following.
Apache CXF Web Service Development
Spring In Action
Please be aware that J2EE and Spring are not evolutionary linked to each other Spring was more a reaction to the heavy weight J2EE specification of old. CXF is a web services toolkit/API that can be used outside of J2EE as well.
I would suggest you also join the user lists of the CXF projects and ask questions there. Also why not post some of the code causing exceptions here so we can help you with more detail?
I'm trying to put together Google App Engine and Google Web Toolkit for one of my projects.
I think I'm going to use Objectify for data persistence, too.
The guys of Springsource says that integrate those technology with Spring is possible.
Do you know where can I find some sort of tutorial about that?
Spring + GAE == slow start up for every instance.
You will face performance problems.
In my project I had to get get rid of Spring once we had everything implemented :(
I wont use Spring + gae anymore
There is no any extra stuff required, no special configurations, tricks, etc. If you know both Spring and GAE - just use it, it's pretty standard.
I've few project based on Spring+GAE+Objectify+Java/Groovy - everything working fine together.
update:
Spring is good only for server-side part. As you want to use IoC on client side (in GWT part), you can use Google GIN instead. It's Google Guice framework (IoC from Google) designed for using with GWT.
See http://code.google.com/p/google-gin/
I've been reading/learning more about Spring lately, and how one would use Spring in combination with other open-source tools like Tomcat and Hibernate. I'm evaluating whether or not Spring MVC could be a possible replacement technology for the project I work on, which uses WebLogic and a LOT of custom-rolled Java EE code. The thing is, I've always suspected that our solution is over-engineered and WAY more complex than it needs to be. Amazingly, it's 2009, and yet, we're writing our own transaction-handling and thread-pooling classes. And it's not like we're Amazon, eBay, or Google, if you know what I mean. Thus, I'm investigating a "simpler is better" option.
So here's my question: I'd like to hear opinions on how you make the decision that a full-blown Java EE application server is necessary, or not. How do you "measure" the size/load/demand on a Java EE app? Number of concurrent users? Total daily transactions? How "heavy" does an app need to get before you throw up your hands in surrender and say, "OK, Tomcat just isn't cutting it, we need JBoss/WebLogic/WebSphere"?
I don't think that the decision to use a full-fledged Java EE server or not should be based on number of users or transactions. Rather it should be based on whether you need the functionality.
In my current project we're actually moving away from JBoss to vanilla Tomcat because we realized we weren't using any of the Java EE functionality beyond basic servlets anyway. We are, however, using Spring. Between Spring's basic object management, transaction handling and JDBC capabilities, we aren't seeing a compelling need for EJB. We currently use Struts 2 rather than Spring's MVC, but I've heard great things about that. At any rate, Spring integrates well with a number of Java web frameworks.
Spring does not attempt to replace certain advanced parts of the JavaEE spec, such as JMS and JTA. Instead, it builds on those, making them consistent with the "Spring way", and generally making them easier to use.
If your application requires the power of the likes of JMS and JTA, then you can easily use them via Spring. Not a problem with that.
Google open sources a lot of their code. If you're writing low-level things yourself, instead of implementing code that's already written, you're often overthinking the problem.
Back to the actual question, Walmart.com, etrade.com, The Weather Channel and quite a few others just use Tomcat. Marketing and sales guys from IBM would have you believe different, perhaps, but there's no upper limit on Tomcat.
Except for EJB, I'm not sure what Tomcat is missing, and I'm not a fan of EJB.
What tomcat does not offer apart from the more exotic elements of Java EE is session beans (aka EJBs). Session beans allow you to isolate your processing efficiently. So you could have one box for the front end, another for the session beans (business logic) and another for the database.
You would want to do this for at least 2 reasons:
Performance; You're finding that one box to handle everything is loading the box too much. Separating the different layers onto different boxes would allow you to scale out. Session beans are also able to load balance at a more fine grained level. Tomcat and other web services of that ilk don't have clustering out of the box.
Flexibility; Now that you've moved your business logic into its own environment you could develop an alternate front end which used the same layer, but say, was a thick client front end for example. Or maybe other contexts would like to make use of the session beans.
Though I should probably point out that if you use web services to communicate with that middle tier, it could also be on tomcat!
The only reason to use a full blown Java EE server is if you need distributed XA transactions, if you don't need XA transactions then you can use Spring + JPA + Tomcat + Bean Validation + JSTL + EL + JSP + Java Mail.
Also a Java EE server is supposed to implement JMS but it does not make sense to run the JMS server in the same VM as the rest of the app server so if you need JMS you should have a separate JMS server.
I strongly disagree with all answers given here.
Everything can be added to Tomcat, including EJB, CDI, JTA, Bean Validation, JAX-RS, etc.
The question is: do you want this? Do you want to assemble all those dependencies in the right versions and test that it all works together, when others have already done this?
Let's be clear: nobody uses only Tomcat! Everyone always adds a web framework, an ioc container, an orm, a transaction manager, web services, etc etc
Lightweight Java EE servers like TomEE already include all of that and makes the full stack experience of having all those things integrated so much better.
Maybe this can be of interest:
http://onjava.com/onjava/2006/02/08/j2ee-without-application-server.html
HTH
Spring roo is new framework and I found it very interesting. I have been working on web application for last 3-4 years and Always found JSPs are hard to maintain across teams if everyone is not disciplined enough about separation of markup and serverside logic. I have used JackBe/BackBase in last projects and I enjoyed xml templates working as views. This was much better than JSPs. But I couldnt automate webtests through selenium for backbase.
I would be surely using Spring MVC (-view), Hibernate on the backend. I found Wicket as good alternative. Have you used wicket along with Spring and what was your experience?
First, Spring Roo is a code generator tool (similar to Grails commands system):
(source: springsource.com)
Second, Spring Roo applications currently use Spring Web Flow for the view and Spring for the glue.
So, while you can compare (Spring Web Flow + Spring) and (Wicket + Spring), the later combo doesn't offer anything comparable to Roo out of the box (maybe AppFuse or AppFuse Light but you didn't mention them and they are third-party projects).
In other words, I don't think that "Spring Roo vs (Wicket and Spring)" makes sense.
Our current project uses Spring and Wicket, we have always used Spring but switched to Wicket a year ago. Few advices:
Get the "Wicket in Action" book.
The user mailing list is very helpful.
Make sure you understand Wicket's programming model especially the session serialization related stuff (the book does not help enough in this area IMHO).
Wicket is good at building stateful pages, it requires more work to build stateless pages.
There are some good UI widgets available like inmethod DataGrid.
It's easy to inject your Spring beans in your pages or components.
Spring Roo is still in beta (1.0 M2), so it may be a little early.
We also considered Tapestry 5 but we thought it was a bit young a year ago.
Spring Roo 1.0.0 (GA) has now been released, complete with around 100 pages of documentation.
If you're wondering about what Roo is and why use it, I recommend you take a read of the introductory chapter of the reference guide. It covers this and more.
#Antony, GWT support is a major priority for Roo and something I am currently working on. Expect to see some interesting integration in the very near future.
I was at the SpringOne conference in Amsterdam earlier this year when they announced Roo. My impression (and that of my colleague who was there) was that Roo was good if you were generating a web-based CRUD application every few weeks - they pitched it as the pure Java version of Grails (which is RoR for Java).
Didn't look interesting for anyone else - but that's just an opinion.
I've seen a demo of Roo a few months ago. It looks a lot like Grails (another spring technology), except that instead of creating artifacts for the Groovy language, you create them for Java.
Still it enforces good practice and makes you apply the MVC pattern in a clean way.
Personally, the demo didn't make me change my preferred toolkit (Grails), but that's because I can achieve faster results with Groovy (parsing xml for example is much more "painful" in Java than in Groovy). Also, with Grails I can see the changes I make instantly without having to recompile my entire project and relaunch the application each time I want to see the results.
Last but not least, in Grails you have tons of plugins to make fancy Ajax websites (ZK for example, if you want to avoid Javascript, but there are plugins for GWT, Yahoo, Dojo, etc...).
So, if you don't want to learn Groovy (which is not too difficult if you already know Java), Roo is the way to go to build clean web projects with all the power of Hibernate and Spring.
I hope this helps...
Why use Roo when one can build something w/ GWT and end up w/ a far richer better outcome and without the constraints of Roo and its architecture. Spring Web Flow is yesterdays technology.
It completely depends on what your requirements are. If it's a small site then Component Oriented frameworks like GWT or Wicket are a must as they make things really easy.
How soon with Roo support GWT? I think that the use of GWT by Roo makes it a huge win for GWT and Roo!
Roo and GWT are available today in pre-release form. In my opinion, definitely not ready for prime time.