Develop Reference

Can't we use spring for distributed java applications?

This came as an interview question.
The interviewer asked me if you can use spring for all the purposes and get away without using any of the Java EE framework .
I said yes, but he asked me how about if the application is distributed and what is the point of application servers.
I am not sure about the answer.
Does Spring do everything that the Java EE framework does?

Well, Spring is wide. So you can review point by point. I'm not specialist in Java EE but I'm sure Spring can cover a lot (if not all) of Java EE concerns. And I'm pretty sure Spring can handle most of layers/concerns in an application.
First of all, Spring IOC. You can configure an object graph with Spring IOC. It helps at any layer configuring all the components you need to implement a layer.
Spring-MVC-Web: you can configure an MVC web component in order to handle and serve all web application requests. I think you can make something cool with it. Configure web responses and its necesary configuration with other business elements (including IPC - Inter Process Comunication).
Spring Security is heritage from Acegi. It's a web framework for defining role-defined access to web resources.
I'm not sure if Hessian is Spring's too. Anyway it's lightweight and it helps comunicating with components in other processes à la RMI.
Well... I'm not sure about persistence, but I thing Spring has templates for JDBC, Hibernate, and all, so it can help anyway (as suggestions indicate: JmsTemplate and RestTemplate are available for communication with other business components!).
The core thinking here is: you can make an app from scratch, so in all cases, Spring can provide a framework to ease the difficult/repetitive tasks on every layer. Does Spring does it? Yes.
Please check other features to see if Spring has something for it. I'd bet it.

Deep down, Java EE is a set of specifications (some of which have been contributed by Spring team!)
Spring's mission statement is to 'Simplify Java Development'
It does so using the following techniques:
POJO -> facilitates easy testing
DI -> promotes loose coupling
AOP -> promotes separation of concerns, maintainability etc
Templates -> provides a standard programming model which does the heavy lifting for you
Spring and Java EE do not have a "Vs" relationship.
Using the above techniques, the Spring Framework lets you build (Java EE) standards-based applications more efficiently.
>Does spring do everything that the Java EE framework does ?
Based on what I've said above, the question might be rephrased as 'Does Spring have support/implementations for all the technologies that comprise the Java EE specification?' -
Nope, but it does do what it set out to do and that is simplify development on most Java EE technologies.
That said, the trade-off for this simplification of Java development is that you need to now have significant amount of knowledge (of the Spring Framework) at your fingertips... (comes with practice and google :) )
>Can't we use Spring for distributed java applications?
Sure you can. Spring has a whole lot of Exporters/FactoryBeans and Clients(Templates) for most conceivable use cases.

Yes Spring can be used in a distributed application without Java EE. We have used it to send messages to MQ and update a database both within one XA transactions.
According to this article, Spring can definitely be used on its own in a distributed application.
http://www.wrox.com/WileyCDA/Section/Why-Use-the-Spring-Framework-.id-130098.html
http://www.artima.com/forums/flat.jsp?forum=276&thread=204508

Historically, (5 years ago?) Spring was weak in the distributed applications area, in particular database clustering. That is no longer a concern. I would say that Spring is going even further for distributed computing these days as they are vigorously pursuing cloud technologies which Java EE hasn't approached yet.

In my view the main benefit of Spring was that it did away with some of the more heavyweight components of the Java EE framework (Entity Beans, session beans) and replacing them with a lightweight alternative.
On of the main benefits of Spring as I see it, is that it decouples a lot of components and then uses XML or Annotations of wiring them together. That makes it easy to write Unit Tests (by injecting mock components instead of real ones), which wasn't something easily done when using heavyweight Java EE components (couldn't easily unit test EJB 2.1 Entity Beans).
A lot of Spring concepts have since gone into the Java EE standards, so I would argue that Java EE is no longer a heavyweight option, and Spring works will with Java EE components such as application server managed connection pools (via JNDI), transaction managers, queue managers that can very easily be managed using an application server which can provide additional functionality such as clustering, failover, load-balancing, serving web resources...
Having said that, the people behind Spring (VMWare) have their own application server (tcServer) which is based on Apache Tomcat and provides a lot of the glue used by spring, but is not considered as "heavy" as some of the traditional Application servers (Websphere, Weblogic).

I don't think so. Basically Spring is about integration between Java EE frameworks.

Use spring inegration framwork for this .
Use can uss Akka framwork for managing distributed applications with spring integration .
Akka uses the Actor Model together with Software Transactional Memory to raise the abstraction level and provide a better platform to build correct concurrent and scalable applications.
Take a look at the step by step tutorial that gives more information about how to build a distributed application using Akka framework.
In general, distributed applications are built in Java using Java-RMI that internally uses Java's inbuilt serialization to pass the objects between the nodes.

Which technology to use with EJB project

I'm developing java enterprise web application using EJB 3.1 and I wonder which technology to use on which MVC layer. I have ear, ejb(jar) and war projects.
Is it possible to use something other as persistence layer then JPA implementations (e.g. myBatis) and how? I would like to manage some more difficult queries on my own.
What framework to use in web project (war) except JSF or plain servlets?
I'm familiar with Spring, would it be possible to use Spring in web (war) projects and benefit from its controllers?
Can you explain which technologies are used to develop enterprise web applications?
Thanks.

The best combination would be to use what's already there. JSF 2.0 is already one of the best MVC frameworks, so it would often be a first choice anyway.
When using EJB 3.1, this is almost always in combination with a Java EE implementation, so in that case JSF is already there and simply using it is a no-brainer.
The different technologies in the Java EE stack are made to work with each other, so a typical stack consisting of JSF + CDI + EJB + JPA is the most ideal combination and you'll find the most support for this.
I personally don't think there's any place for Spring in an EJB/CDI stack. Those two technologies are direct competitors that solve the same problem in (slightly) different ways. Combining them will most likely only complicate your code.

For a starter like you, stick with what comes out of the box with Java EE 5/6. So in your case JSF+Facelets, EJB 3.1 and JPA.
I suggest you to read the below books and in the order given
Beginning Java™ EE 6 Platform with GlassFish™ 3
Real World Java EE Patterns Rethinking Best Practices

Starting a Java project - IDE, Framework, etc. -

I need support in order to speed up development process. I received a request to start developing a website with java technology. I usually develop in C# - ADO for Entities - ASP.NET MVC - MSSQL server - Visual Studio. Best of these choices were:
- C# Intellisense.
- ORM.
- Complete Security Management of Users, Roles.
- Separation of Concerns into MVC.
I was wondering if any can help me to determine best Java MVC Framework - DB - IDE based on these premises, Start a project with:
- Integrated security for users, roles
- MVC
To shed more light, to replicate same functionalities I can have each time I start a website using C# ASP.NET MVC 2 project. example http://nerddinnerbook.s3.amazonaws.com/Images/image020.png

First, let's discuss IDE, ORM, and security, and DB: In my opinion, the best Java IDE is IntelliJ IDEA. It's from the same folks who have developed Resharper for Visual Studio. It has the most powerful editor of all Java IDEs and has built-in support for many popular Java frameworks.
ORM: The most powerful ORM library in Java is Hibernate. Hibernate itself is an implementation of Java Persistence API (JPA) standard. EclipseLink is another implementation of JPA, but Hibernate is a better option IMO.
Security: Spring Security is probably the most powerful security (authentication and authorization) framework available in the Java world.
DB: If you are comfortable with SQL Server, then keep on using that. However don't use Microsoft's JDBC drivers. Instead use a driver from DataDirect: http://web.datadirect.com/products/jdbc/index.html. If you don't want to use SQL Server, MySQL is a great FOSS choice and Oracle, DB2, etc. are other options.
For the Web framework, there are several options:
Option 1: If you want a RAD style framework, choose Grails. Grails is similar to Ruby on Rails but uses JVM and a Java-like but dynamic language named Groovy. Grails' ORM API is called GORM, which is built on top of Hibernate, but is much easier to use. Grails also uses Spring Security for managing security.
Option 2: If you want an enterprise-grade framework, choose JBoss Seam + JavaServer Faces. JSF is a component-based MVC framework, and there are plenty of great JSF libraries available for use: RichFaces, OpenFaces, etc. Seam integrates JSF with EJB and together they make a great enterprise framework. However it has a steep learning curve.
Option 3: Use Spring + SpringMVC + JPA.
Option 4: Use Struts 2 .
Final remarks: If you are looking for an easy-to-learn MVC + ORM framework, use Struts 2 + JPA. If you are looking for a RAD and easy-to-use MVC + ORM framework, use Grails. If you are looking for a robust and enterprise-grade (but not-easy-to-learn) framework, use JBoss Seam.

Not only Spring MVC but the whole Spring eco system will get you up and running with the least surprises. You can also download the Spring Tool Suite (a preconfigured eclipse version tailored for Spring) to get an integrated development environmanet which knows about all spring stuff.
But Spring - Spring MVC - Hibernate - Spring Security and STS seems to cover your needs and will provide a sound basis to do the project without too many bad surprises. This leaves you to focus on the customer and the jump to Java.
Afterward you might consider different options in the Java space, as there are plenty of other frameworks available with their strong points. But in the short run it is better to limit the number of moving parts

The standard, most common framework/orm setup is spring/hibernate. Both of these tools have unfortunately been grown to ridiculous extremes over the years, so they may seem daunting in size, but a simple setup with each is much easier than it may seem from looking at all of the options on their respective sites.
Best suggestion would be to follow a step-by-step to get a basic spring/hibernate setup going and just expand off of that. At one point I had a prototype project like this I'd use to generate a "starter-set" to bootstrap projects.
BTW, I'd also suggest a simple ant build script. Some people may suggest maven, but it's enormous and very (imo overly) complex, and you're going to have enough new tools to wrap your head around to want to avoid having to learn another large command set.

Welcome to the Java world. The best thing (and in some cases also the worst thing) about the Java domain is that you can create your own stack based on your requirements. You're not necessarily bound to a single vendor as is commonly the case in the .NET domain.
Since it seems you're in a greenfield situation you can:
Adopt the webdevelopment stack of a large commercial vendor like Sun/Oracle (JSF/EJB3 + NetBeans/JDeveloper + Glassfish/Weblogic + MySQL/Oracle) or IBM
Adopt the webdevelopment stack of a smaller open source vendor like JBoss, SpringSource.
Take a look at JBoss Seam and SpringSource Grails and Roo (the latter two are based on the frequently mentioned Spring/Hibernate frameworks)
Mix and match your own stack based on the above and your requirements. Although this requires deep knowledge of the various technologies, frameworks, tools available.
You have lots of options as you can see. Now since your interested in a productivity focused stack - and I suspect an opensource one - and you have no legacy I recommend either Grails or Roo. In which Roo is probably the most accessible one since you don't have to learn Groovy. If you don't like the generation tooling I advice you the stick to the Spring stack and just adopt Spring/JPA/etc.

As for IDE, the only Java IDEs worth their salt IMHO are Eclipse and Netbeans, especially since both of them are free. Use Eclipse for extensibility and ease-of-use, use Netbeans if you need to rapidly develop a GUI.

What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?

May I know what is the difference between:-
Spring
Struts
Struts 2
Hibernate
JavaServer Faces
JavaServer Pages
Tapestry
Are these technologies/framework complementary to each other? Or they are alternatives to each other (after I use one of them, then I don't need to use the other)?
Thanks.

Spring is an IoC container (at least the core of Spring) and is used to wire things using dependency injection. Spring provides additional services like transaction management and seamless integration of various other technologies.
Struts is an action-based presentation framework (but don't use it for a new development).
Struts 2 is an action-based presentation framework, the version 2 of the above (created from a merge of WebWork with Struts).
Hibernate is an object-relational mapping tool, a persistence framework.
JavaServer Faces is component-based presentation framework.
JavaServer Pages is a view technology used by all mentioned presentation framework for the view.
Tapestry is another component-based presentation framework.
So, to summarize:
Struts 2, JSF, Tapestry (and Wicket, Spring MVC, Stripes) are presentation frameworks. If you use one of them, you don't use another.
Hibernate is a persistence framework and is used to persist Java objects in a relational database.
Spring can be used to wire all this together and to provide declarative transaction management.
I don't want to make things more confusing but note that Java EE 6 provides modern, standardized and very nice equivalent of the above frameworks: JSF 2.0 and Facelets for the presentation, JPA 2.0 for the persistence, Dependency Injection, etc. For a new development, this is IMO a serious option, Java EE 6 is a great stack.
See also
Choosing a Java Web Framework now?
Java - JDBC alternatives
JEE6 vs. Spring 3 stack
What to learn for making Java web applications in Java EE 6?

Generally...
Hibernate is used for handling database operations. There is a rich set of database utility functionality, which reduces your number of lines of code. Especially you have to read #Annotation of hibernate. It is an ORM framework and persistence layer.
Spring provides a rich set of the Injection based working mechanism. Currently, Spring is well-known. You have to also read about Spring AOP. There is a bridge between Struts and Hibernate. Mainly Spring provides this kind of utility.
Struts2 provides action based programming. There are a rich set of Struts tags. Struts prove action based programming so you have to maintain all the relevant control of your view.
In Addition, Tapestry is a different framework for Java. In which you have to handle only .tml (template file). You have to create two main files for any class. One is JAVA class and another one is its template. Both names are same. Tapestry automatically calls related classes.

You can see the overview and ranking for yourself here. Hibernate is an ORM, so you can use either struts+Hiberante or spring+hibernate to build a web app. Different web frameworks and many are alternatives to each other.

Spring is an application framework which deals with IOC (Inversion of Control).
Struts 2 is a web application MVC framework which deals with actions.
Hibernate is an ORM (Object-Relational Mapping) that deals with persistent data.

In short,
Struts is for Front-end development of website
Hibernate is for back-end development of website
Spring is for full stack development of website in which
Spring MVC(Model-View-Controller) is for Front-end.
ORM, JDBC for Data Access / Integration(backend). etc

In hibernate you need not bother about how to create table in SQL and you need not to remember connection ,prepared statement like that data is persisted in a database. So, basically it makes a developer's life easy.

Spring is a light weight and open source framework created by Rod Johnson in 2003. Spring is a complete and a modular framework, Spring framework can be used for all layer implementations for a real time application or spring can be used for the development of particular layer of a real time application.
Struts is an open-source web application framework for developing Java EE web applications. It uses and extends the Java Servlet API to encourage developers to adopt a model–view–controller (MVC) architecture. It was originally created by Craig McClanahan and donated to the Apache Foundation in May, 2000.
Listed below is the comparison chart of difference between Spring and Strut Framework

Tapestry pages and components are simple POJO's(Plain Old Java Object) consisting of getters and setters for easy access to Java language features.

Difference between Spring, Struts and Hibernate are following:
Spring is an Application Framework but Struts and hibernate is not.
Spring and Hibernate are Light weighted but Struts 2 is not.
Spring and Hibernate has layered architecture but Struts 2 doesn't.
Spring and Hibernate support loose coupling but Struts 2 doesn't.
Struts 2 and Hibernate have tag library but Spring doesn't.
Spring and Hibernate have easy integration with ORM technologies but Struts doesn't.
Struts 2 has easy integration with client-side technologies but Spring and Hibernate don't have.

How to boost productivity in my Flex/Java stack?

I am embarking on a new RIA project with Java on the backend. I'm the only developer, and the app is a line-of-business application. My current stack looks like this:
MySQL || Spring(JdbcTemplate for data access) || BlazeDS (remoting) || Flex(Cairngorm)
My question is: what changes can I make to improve productivity? Manually coding SQL, server-side entity objects, client-side value objects and all the Cairngorm stuff is obviously a drag, but I'm not sure what higher-level frameworks to introduce.
What Flex/Java stack has served you well?

Manually coding SQL
Hibernate is an option to cut this out.
One thing that may be of interest is Grails with the available Flex Plugin. It's built on Spring, Hibernate and BlazeDS, so it's all there for you. It was unbelieveably easy to get it remoting stored objects and responding to AMF calls. I was using this and then moved over to a RESTful E4X implementation as I found it a lot easier to debug and tweak as I could inspect the server output in a browser and have tighter control over exactly what I returned to my Flex app (lazy loading problems in collections using BlazeDS were a headache at times).
Here is a quick tutorial showing how easy the whole Grails + Flex Plugin stack is: BlazeDS in Grails

I would seriously reconsider using Cairngorm. In my opinion it's a pretty bloated framework that introduces a lot of abstraction you'll never use. Check out:
http://code.google.com/p/swizframework
http://www.spicefactory.org
Both introduce the concept of dependency-injection into your Flex app.
Also +1 for Hibernate. I would use the standard JPA annotations on a Java class and extend that with Hibernate Annotations as you find you need additional functionality.

Check out springsource.org's new Spring BlazeDS Integration Project
Spring BlazeDS Integration is a new
addition to the Spring portfolio, and
a component of the complete Spring Web
stack. This project's purpose is to
make it easier to build Spring-powered
Rich Internet Applications using Adobe
Flex as the front-end client. It aims
to achieve this purpose by providing
first-class support for using the open
source Adobe BlazeDS project and its
powerful remoting and messaging
facilities in combination with the
familiar Spring programming model.

As alternative to hand-coding sql, aside from hibernate, you might wanna consider JPA/Toplink. And since you are already from a Spring camp, check out Spring ActionScript (formerly known as Prana), it's an IOC framework for Flex. It solves many inherent problems in Cairngorm. Also a good IDE that supports Flex/Actionscript like IntelliJ IDEA 8.
Whats missing between Flex and BlazeDS is, it doesnt have any sort of landing page where you have a listing of all the available services by just typing a url on the browser (similar to webservice endpoint).

You can try GraniteDS. It's an alternative to BlazeDS, with an actionScript generator, Spring integration (an Spring security), and if you use an JPA implementation, help you with the Lazy Initialization (in a transparent way).