We currently have a 2-tier Java Swing application sitting on top of MS SQL Server 2005. All the business logic is in the database. The client is quite old (and not very friendly), and for reasons of performance and scalability, we've already started porting some services to a middle tier in Java.
However, we still have a number of short and long term goals:
Pick a technology stack for a new front-end
This isn't easy - I can see everything from a web app at one end of the continuum to a traditional desktop app at the other being viable choices. The current front-end isn't really complex (mostly form-based), so I can see web/AJAX fitting, but it's an area where we don't know what we don't know.
Stacks on my list are:
Eclipse RCP, Netbeans RCP
Flex/Flash, Silverlight, JavaFX
Pure Javascript frontends (Sprout Core, Javascript MVC, ...)
Java-based Web frameworks (Wicket, JSF, ...)
Find a way of making the current application perform acceptably in a remote situation
We have some clients who resale our app to smaller clients and need to be able to remotely deploy it. Due to the 2-tier nature of the current architecture this leads to terrible performance (for example, calling a stored procedure that returns 18 result sets). We've used a Citrix solution in the past, but no-one likes that approach. Tunneling JDBC through port 80 also sounds like a bad idea. I was starting to wonder if there's anything that could use a X-Windows like approach to remote just the GUI part.
To simplify development and leverage your experience in Swing consider using Vaadin for your frontend. It is a Java framework for building modern web applications that look great, and perform well. All the code is written in Java and looks very similar to Swing.
As far as overall application architecture I would advise multi-tier, service oriented architecture. The best way to do it is by using Spring framework with Hibernate for database access.
If you want to easily redeploy your application, for an update, security reasons, etc. and if you want your application to be it to be accessed remotely, you should really consider a web based front end.
Plus, this way, only one app, your web app, will handle connection to the database, so no JDBC tunneling or whatever.
Concerning the best framework, it depends on your team knowledge, the way your application will be used (more or less javascript), etc.
We've just gone through a very similar evaluation process as we're migrating a legacy application.
For us the biggest deciding factor in what front-end framework to use was the prior knowledge of the development team. We wanted something that everybody would be comfortable with immediately. We had a couple of the senior developers that have worked with X or Y, but the framework that everybody knew was Swing.
In the end we decided on the NetBeans platform using RESTful webservice to communicate with an EE server.
As a bonus you can get your NetBeans platform application to deploy as a Java WebStart application, which means you get the benefit of not having to worry about individual installations.
If the frontend is mostly form-based, I would stay away from Flex. Flex is great for some applications (I'm using it for a canvas based application), but the form components of Flex has some usability issues. They just don't work like you expect from todays web. (like missing support for mousewheel, typing in dropdownlist only take first character into account etc.)
Assuming that you are going to force all your clients to install a new middle tier, I can't think of an argument against making it a Java web app. As already mentioned you have the benefit of controlling all access into your platform over HTTP, which allows easy resale, just with firewall configuration. There's no reason you can't make use of Javascript within a web front end, you may be interested in DWR, which allows you to interact directly with Java objects via Javascript. I've used this before to add some simple Ajax interaction to a Spring MVC webapp.
The reasons I like this approach, you're already migrating code into Java middle tier, so
Already imposing Java server hardware cost on clients, hosting app server / web server is comparable
Already have Java expertise, can be leveraged with DWR
Can use as much/little Javascript as appropriate (I've used DWR with IE6, Firefox 3, Chrome)
I think you're right to be wary of pushing too much functionality to the client, I'd go for as thin a client as possible. The only reason I'd look at the first two stack choices would be if you have some developer expertise in a particular area, and not Java webapp/Javascript.
I'd suggest to create a short list of candidate frameworks and create a small test application with all of them. This way you will get a sense of good and bad aspects from all of them and also get a picture what the community activity and documentation is like for each project (there is a lot of variance on those).If you end up doing this I hope you'll include Vaadin in your short list, I think it would fit you very well. If you have any questions just come over to our forums and we'll help you to get started.
Related
I'm carrying out a feasibility study on writing, let's say it's a lightweight run-in-browser MMORPG. (It's not exactly an MMORPG, but would take longer to explain, and the requirements are similar.) I'm trying to figure out the required technology stack.
Client side, it runs in the browser, so the client is Javascript. That was nice and easy :-)
Server side, I'm looking at Java. The common Lamp stack was designed for RESTful applications, as I gather were typical Java web frameworks, and this application is different - it needs a continual stream of data going back and forth between the server and all the clients. I think what I need in this case is Java of the non-framework, full no-holds-barred Java EE variety, someone please correct me if my understanding is incorrect or incomplete? I would need something that is commonly available on reasonably cheap hosting, Java EE fits this description, right?
(Figuring on using MySQL for the database, as this is what's most commonly available. Also I might actually write the code in Scala, being a Java-compatible but supposedly slightly nicer language. I assume neither of these makes any difference?)
Supposing I were writing a website in Lamp, doing at least the initial development on Windows, then I'd install Xamp, which gives you a running copy of the entire server stack right there on your desktop, so you can just alt-tab back and forth between your editor/IDE and browser for testing.
Now my question is: What's the best equivalent setup for Java, for developing something like this on Windows?
Right, in a sense it is. What I think I'm really saying is that almost all discussion of server-side Java seems to talk about JSP, EJB, Glassfish, Google app server etc which are frameworks in the sense that they put restrictions on what your code can do, whereas Java EE puts no such restrictions, you can use as much or as little of the standard library as you want, but it doesn't stop you running arbitrary persistent Java code. Is that correct?
You've thrown out a bunch of terms there:
Glassfish is an application server that implements (all of) Java EE.
JSP is a specification that is part of Java EE, and implemented by application servers such as Glassfish as well as web servers such as Tomcat and (I think) Jetty.
EJB is another specifications that are part of Java EE. It is typically implemented by application servers.
"Google app server" is really "Google Application Engine" (GAE), and is really a platform for implementing web servers in a cloud computing environment. If that's not what you want / need to do, GAE is probably a blind alley for you.
Glassfish, JBoss, Tomcat, Jetty and so on are all platforms that implement some or all of Java EE. None of them stop you implementing arbitrary persistent Java code.
GAE on the other hand does restrict what you can run, because the platform only allows you to run standard Java classes in a whitelist. If your "arbitrary" code depends on other standard Java classes, you are out of luck. (And hence my warning about blind alleys.)
And of course, there are various other Java-based frameworks that are targeted at web development in one form or another. Some are compatible with Java EE servlets and other EE technology, and some have gone off in a different direction.
My recommendation would be to start with something straight forward using plain servlets on a stock platform. Only look at the high performance stuff if and when performance looks like it will be a real concern (not just a "nice to have"). It is better to have a simple and non-scalable prototype, than a high performance solution that you don't have the time and skills to get working. And you can treat the prototype as a learning exercise.
A little hard to tell from the requirements given, but I would look at the following based on your description:
http://www.playframework.org/
http://www.zkoss.org/
http://code.google.com/webtoolkit/
Play Framework is a nice web-centric framework that provides a complete stack (you can code in Java or Scala). ZKoss (ZK) and GWT both provide user interface frameworks. ZK, GWT, and Play all run nicely in Tomcat/MySQL and should work just fine in typical Java/MySQL hosting environment.
... not sure what your definition of 'cheap' is but, that and 'no holds barred Java EE' don't exactly go together. Also, 'frameworks' by themselves don't put restrictions on running any arbitrary java on the server side. When I say 'frameworks' I mean Spring, Struts, etc. Servers will be a little different story. If you need EJBs you'll need Glasfish or JBoss or another EJB compliant container. Hosting with these will be more expensive compared to getting by with Tomcat. IMHO easiest and quickest way to get started is with NetBeans. Comes with Tomcat and / or Glassfish out of the box, all you need is a db.
The company I work for has a powerful Java based server component framework for interacting with special control systems.
We have a UI framework but this is also Java based. A customer can use a Java Applet to access control information etc.
I've recently started working on a rich JavaScript API to access this control system information remotely. It's currently a prototype. It's nice because anyone who's familiar with JavaScript can access our Components remotely. So far it works really well. I've written some prototype applications that use this API. This gave me an introduction to jQuery - great! I've also added the ability for the JavaScript API to make RPC calls to Java as well as a session based Component architecture for when you really need something held on the server.
So far so good. I have to admit though that I'm not really a 'web developer'. I've never used Structs, Spring or any of the MVC based architectures for serious Enterprise based web development (I AM very familiar with design patterns though). My background is application development.
I'd like to know from the pros whether this is the right approach or whether I'm missing anything. Someone I work with has created a really neat Server Side Include architecture. However, I'm wondering now whether this is really necessary? After, I think I can create just about anything using my JS API and jQuery. Should I consider any other 'server' based architectures in this new age of open web apps?
As far as browser support goes, I'm not concerned about the older generation of browsers (please no lectures here, the old technologies we've got will do for IE6 and alike).
By using this open client side technologies, I'll be able to write sophisticated open web apps. Very little server side code will be needed in reality because of my API. I'll be able to take advantage of HTML 5 features etc. But am I missing anything? Should I be considering other server side based Java technologies like Server Side Includes? Am I too client focused?
Well there are four ways to create modern RIAs: HTML5/Javascript, Java Applets, Flash/Flex and Silverlight. Only the first two are open.
Applets are a nuisance and not really liked by people. Personally I'd go with HTML/Javascript.
Since you are a Java shop I'd recommend going with GWT for the following reasons:
It's open source with business-friendly license.
It creates minimum-size browser-optimized javascript.
It's actively developed and used by Google. This is a guarantee that it'll be supported for some time.
There are a lot of developers with knowledge of it.
It has good documentation and very active user group.
I'm sure there are many opinions on this, but my take is that with HTML5, faster Javascript interpreters, client side persistent storage, etc. it makes it pretty compelling to put all the UI application login in the client (browser), and just use some form of RPC (with JSON serialization) to the server. Therefore templating engines, SSI, or any server side generated markup is no longer required for interactive applications. It's still fine for semi-static documents. For that I use sphinx document generator.
Fast-forward two years, and you now have TodoMVC at your disposal to help answer this question. GWT is still mentioned, though as far as server-side technologies go, The Holy Grail is probably what you're looking for to maximize code reuse on client and server.
We are occasionally in a position to take over PHP based projects, but as we are a Java-house we are searching for ways to turn a PHP-project (or codebase) into a Java-project.
The approaches we came up to work in a mixed Java/PHP context are :
PHP in frontend and Java in backend with separate front (PHP+JavaScript) and back (Java+SQL) teams
using both technologies in a Java webapp, for example via Quercus with one or multiple teams
migrating everything to Java
We haven't tried any of these approaches as we've been lucky enough to have enough Java-only projects to work on.
Do you see other approaches, or have you tried any of the described approaches?
I've used Quercus. I think that if it supports something like Drupal then it's probably fairly mature. If your PHP app works out of the box, then it offers you a very gradual upgrade path to Java since you can write your own plugins in Java and expose them to the PHP layer, such as using a JDBC back-end.
How easy it is all depends on how well separated the layers are in the PHP application. For example, if the view layer is well separated, you might be able to replace both controller and model logic with a Spring MVC application that uses a 'QuercusView' for the view - you may be able to re-use a lot of the PHP view logic.
You should also consider how you can make a survey of the PHP code - maybe a script that extracts all the function calls, imports etc. so you can quickly test the Quercus support for them.
Sorry, I haven't used the PHP-Java bridge, but I think the Quercus library is pretty mature these days, so that would be my first choice for a staged migration.
My experiences with Querces are not so good. Maybe it has improved, but when I tried it something like two years ago (a long time, I know) it was far from complete and did not support all functions yet. Also, if your application is using some extensions (e.g. from PECL) you will experience difficulties getting this up and running under Querces.
We're currently in the process of migrating a web application from PHP to Java. We're designing a SOA and we'll probably replace some data access objects in the PHP application with a version that talks to internal webservices. Currently we're using Thrift as protocol for our internal webservices, a framework that also has a client available for PHP. We expect this to increase flexibility during migration (allowing us to do step-by-step migration, rather than all-at-once)
PHP/Java Bridge may be of your interest:
The PHP/Java Bridge is an
implementation of a streaming,
XML-based network protocol, which can
be used to connect a native script
engine, for example PHP, Scheme or
Python, with a Java virtual machine.
It is up to 50 times faster than local
RPC via SOAP, requires less resources
on the web-server side. It is faster
and more reliable than direct
communication via the Java Native
Interface, and it requires no
additional components to invoke Java
procedures from PHP or PHP procedures
from Java.
NUMITON may be useful for you:
http://java.dzone.com/announcements/automated-translations-php-jav
The shortest route from PHP to Java
Numiton offers an automated alternative to migrating PHP codebase. This way,
established applications can benefit from the advantages offered by Java in its
enterprise-level capacity.
Some of the risks inherent to any software migration are avoided by using an automated
translation tool. Our PHPtoJava product performs variable type inference,
objectualization and other operations in a uniform manner, the resulting appearance and
behavior being identical to what the users already know.
Of course, the human factor still plays an important role in the post-translation
phases: application fine-tuning and functional testing. The speed and accuracy of the
entire process surpass however those of a manual translation.
One of the applications we have migrated this way is the well-known forum engine
phpBB. The translation result, nBB2, powers our own forum and was recently donated to the
open-source community as a SourceForge project.
PHP in frontend and Java in backend
with separate front (PHP+JavaScript)
and back (Java+SQL) teams
This is technically feasible using SOAP.
using both technologies in a Java
webapp, for example via Quercus with
one or multiple teams
I have no idea about this
migrating everything to Java
This is better option, but it will take time depending on the size & complexity of your project.
I do not have any experience running PHP inside a JVM, but I am betting that IBM does. :)
You might consider Project Zero.
http://www.projectzero.org/php/
Seems similar to Querces or that other thing someone linked. The only other thing that you didn't mention that I can think of is to refactor the PHP code because I'm assuming that its an older codebase written in a PHP 4 manner.
I know this is 2 years old question but i still want to contribute. We are migrating from full java portal to php+java. We have 14 million users. This design doesn't need web services because we use java as json provider for php and js. We will see the result soon...
PHP in frontend and Java in backend with separate front
(PHP+JavaScript) and back (Java+SQL) teams
I need to make a web app that I would be able to install as a desktop application on a client PC (database, jetty+war, firefox/chrome/sth portable).
The application is a quite big search app (I MUST use Lucene). There are only few screens, some dependencies in search queue, etc.
Now I need help in choosing correct components. Application must be:
Light - minimalistic and user friendly frameworks (Java + JavaScript)
Efficient - working on old PCs and working fast
Developer Friendly - I would love to write it with pleasure ;)
So my questions are:
Do you have any suggestions about choosing components?
What frameworks, what obfuscator?
Do you have any comments about making a web application a desktop application?
What are the main risks?
Many Java web apps distributed in this style are done so alongside a lightweight application server or web container such as Jetty or Tomcat.
When you click to start the application, this actually starts the container which internally hosts your application. (You're application can be packaged as a WAR internally.)
For lightweight databases, possibly look at SQLLite, HSQLDB, or Apache Derby. These can also be distributed alongside the application. Or maybe you can just collect database credentials as part of your install process and let the customer maintain their own database.
The arrangement you describe will involve work and custom scripting. You're going to the trouble of creating a thin, multi-user, web application and then throwing away the main benefit - the shared single instance. Customers, eh, who'd have them! :-)
Maybe you could take a look at Google's GWT. You can write Java code and it will then "compile" it to JavaScript. Using it feels like using a desktop app. Gmail, Google Wave,... have been created using this technology.
I think you don't even need a webserver, but the compiled result is pure JavaScript + static HML pages. If you then create a Chrome application shortcut it'll really look like a desktop app ;)
The only thing is that the learning curve will be a bit steep initially but if you're eager to learn, then it's really cool stuff and you can manage it easily.
Ha, I'm in the same boat. But I have many screens like normal web apps.
My suggestions is:
1, take web easy, no framework. Since there's little web pages, html+jquery+css is recommended;
2, lightweight database is not important. Because mysql does cost little memory, and it's user-friendly, large community.
3, So pay your attention on your search engine, and happy coding.
If you have a Java based web application (J2EE webapp - never mind which other underlying frameworks are being used), and you wanted to introduce a Flash based front-end, would you use Laszlo or would you rather expose a ReST-like XML interface and build and deploy a Flash application that uses that?
On one hand, Laszlo is quite amazing - doing for Flash what JSP does for HTML. It is easy to work with. It fits in very well with the rest of the web application (which is JSP based).
On the other hand it might be better to develop a complete Flash app decoupled from the server and use an XML-over-HTTP mechanism to bind the two. This would have the added advantage of being able to use the same XML interface for an AJAX front end if needed.
What would you do, and why?
I would create the contract-first services, deploy them separately, and then write the RIA client to access them.
Coming up with the schema first has the added benefit of completely decoupling the two during development. The RIA developer can create some synthetic XML streams to use for data while waiting for the services to come on-line.
I might have considered Laszlo in the past, but today, I'd stay within the Java stack and use JavaFX.
Laszlo is the product that never made it, there isn't a big enough ecosystem of developers around it.
I'd use Adobe Flex for the front end. The same benefits of using a markup language for doing flash, but it has a much larger developer base and open source projects to draw upon. For the data communication, use either REST or if you want to get clever, use BlazeDS.
OpenLaszlo is a complete RIA framework, so I'm pretty sure that you can 'compile' it to a completely standalone app that communicates with the server over HTTP. It's really very similar to Flex. The advantage Flex has is a much bigger community, a full-blown IDE, and more resources (Adobe), while OpenLaszlo is a little more innovative in that you can deploy to Flash or AJAX from one codebase.
I've actually spent some time working on a implementation similar to what you're suggesting. I had a complied Open Laszlo front end embedded in a web page with a Django (a python MVC library) REST interface on the backend and no Open Laszlo server. It works reasonably well, but there are a couple of things to watch out for. Open Laszlo only supports calls to GET and POST, so you won't be able to easily use the DELETE and PUT methods in your REST API. The other is the lack of community around Laszlo (as mentioned elsewhere). I can sometimes be frustratingly difficult to answer some basic questions when using Laszlo, particularly around the XML HTTP API and XML replication features in the framework. I personally never really looked at the Laszlo back end server seriously as I wanted an open API that could be consumed easily by other clients.
All this being said, the implementation does work and can be effective if you're willing to work around the limitations mentioned above. Plus Open Laszlo is free, which can be a really big plus if your working on a budget.