Does spring have a mechanism which allows multi war projects communicate with each other?
I want to create a solution whereby the features in my application are controlled by a central point (possibly a html page in one of the WAR files) and when an update is made to turn on/off the feature this change is propagated down to the correct WAR which may use annotations or possibly spring profiles to act on the communicated change.
I've looked at a couple of frameworks like Togglz and Fitchy which provide a feature toggle solution however neither is ideal for my requirements.
All suggestions welcome.
Thanks,
Spring have an integration with JMS that can be used in such situation. Check it out. All available options are listed here (including RMI, Spring's HTTP invoker, Hessian, Burlap, JAX-RPC and JAX-WS). Advantage of asyncronous approach like JMS is that it is better from fault tolerance point of view (you can more easily handle the situation where app1 sends a message to app2 which is temporarily turned off). On the other hand if fault tolerance does not metter then some syncronous solution like JAX-WS may be more easy to do. Hope it helps.
Related
I mean the Eclipse preference under Window|Preferences|Spring|Beans Support
"Disable Auto Config Detection".
When this option is not checked, I notice a delay when saving Java files:
Building Workspace...
Loading ...ServerApplication
or
Loading ...DaoConfig
These messages are for Spring Boot main application classes (ServerApplication) or Spring configuration classes with #ComponentScan (DaoConfig) which are located in the workspace.
This can take a few seconds, which is a bit annoying.
When I check the above preference option, I don't notice the delay for loading these classes (at least for the Spring Boot main classes).
What are the consequences of disabling Auto Config Detection, e.g. what does this option really do, what functionality do I loose? Any pointers to documentation?
Can I speed up the save process without having to disable Auto Config Detection?
In STS3, the IDE creates an internal model of your Spring application, so that it can display a nice overview of your Spring elements in the Spring Explorer view, provide content-assist in Spring XML config files and more. In order to build up this internal Spring beans model, it needs to know where to start from when building that model. You can define those entry points manually in the properties for each project: Spring -> Beans Support. That preference allows you to define Spring XML config files and/or Spring-annotated configuration classes to be used by the IDE internally to build up that model.
In addition to that there is a mechanism to detect those files (Spring XML config files and Spring Boot application configuration annotations) automatically, so that you don't need to configure them manually. But the result is the same. Those files/classes end up being configured to be used by the IDE to built this internal model.
I guess that the delay that you see comes from building this internal beans model - this is at least what the messages indicate that you mentioned.
So far for the background. You can disable that auto-config mechanism and you don't need to configure those files/classes manually. This will result in the Spring Explorer, for example, not showing anything meaningful for those projects.
As an alternative and in case you are working mostly with Spring Boot projects, I would strongly recommend to switch to the all-new Spring Tools 4 (also available as a ready-to-use Eclipse distribution). It provides a slightly different set of features and is implemented in a different way, so that it doesn't need the expensive internal bean model creation. You should give it a try. And if you are missing something that you love in STS3 that is not yet part of Spring Tools 4, let us know.
I have a use case where I would like build a common interface or service which can update entities of application. Example case is shown as below:
Now every application has to handle update functionality of entities. Rather than implementing update functionality in n application module. I would like to build a common interface or server in spring boot.
Service will be like below:
My question is how to design service/interface which can used for above scenario. Any api or tool which can help me to achieve this. I dont want to write code for update in every application module.
Thanks in advance.
Last year I was thinking about the similar concept to yours, but in Apache Camel framework context. I haven't got enough time and motivation to do so, but your post encouraged me to give it a try - perhaps mostly because I've found your concept very similar to mine.
This is how I see it:
So basically I considered an environment with application that might uses N modules/plugins that enriches application's features, i.e. processing feature etc. Application uses module/plugin when it is available in the classpath - considering Java background. When the module is not available application works without its functionality like it was never there. Moreover I wanted to implement it purely using framework capabilities - in this case Spring - without ugly hacks/ifs in the source code.
Three solutions come to my mind:
- using request/response interceptors and modifying(#ControllerAdvice)
- using Spring AOP to intercept method invocations in *Service proxy classes
- using Apache Camel framework to create a routes for processing entities
Here's the brief overview of POC that I implemented:
I've chosen Spring AOP because I've never been using it before on my own.
simple EmployeeService that simulates saving employee - EmployeeEntity
3 processors that simulates Processing Modules that could be located outside the application. These three modules change properties of EmployeeEntity in some way.
one Aspect that intercepts "save" method in EmployeeService and handles invocation of available processors
In the next steps I'd like to externalize these Processors so these are some kind of pluggable jar files.
I'm wondering if this is something that you wanted to achieve?
link to Spring AOP introduction here: https://docs.spring.io/spring/docs/5.0.5.RELEASE/spring-framework-reference/core.html#aop
link to repository of mentioned POC: https://github.com/bkpawlowski/spring-aop
I am using Spring framework in my application and it is deployed on MULE server.
Based on debug or info level, the amount of logging and the percentage of logging will vary.
Till date, I write the log statements explicitly in all my business logic.
Is there any way to do this through configuration, say configure at some point -
CLASS NAME - METHOD NAME - LOG AT ENTRY POINT WITH INPUT PARAMETERS - LOG AT EXIT POINT WITH RETURN
This way my code will not look very clutter.
I am not sure exactly what you are asking, but it sounds like you would like to automatically log entry and exit from methods along with parameters. If that is the case, you might consider some form of Aspect Oriented Programing (AOP). Here and here and here are some links to pages with good examples of implementing exactly this kind of logging with PostSharp. Since you are using Spring (.NET or just Spring?), you might know that Spring.NET has an AOP solution (or here for Spring). Here is a project from CodeProject that provides a log4net logging aspect already written for PostSharp (not sure if this is currently up to date or not). There are other AOP solutions out there, PostSharp is one of the more popular.
I answered with a .NET slant because that is what I am more familiar with and you didn't indicate a language preference (via the tags) in your question.
As wageoghe mentioned, using Spring AOP is an option.
Another one, since you're running in Mule, is to use component interceptors around your Spring beans.
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
Does anybody has an experience with Spring Integration project as embedded ESB?
I'm highly interesting in such use cases as:
Reading files from directory on schedule basis
Getting data from JDBC data source
Modularity and possibility to start/stop/redeploy module on the fly (e.g. one module can scan directory on schedule basis, another call query from jdbc data source etc.)
repeat/retry policy
UPDATE:
I found answers on all my questions except "Getting data from JDBC data source". Is it technically possible?
Remember, "ESB" is just a marketing term designed to sell more expensive software, it's not a magic bullet. You need to consider the specific jobs you need your software to do, and pick accordingly. If Spring Integration seems to fit the bill, I wouldn't be too concerned if it doesn't look much like an uber-expensive server installation.
The Spring Integration JDBC adapters are available in 2.0, and we just released GA last week. Here's the relevant section from the reference manual: http://static.springsource.org/spring-integration/docs/latest-ga/reference/htmlsingle/#jdbc
This link describes the FileSucker with Spring Integration. Read up on your Enterprise Integration patterns for more info I think.
I kinda think you need to do a bit more investigation your self, or do a couple of tries on some of your usecases. Then we can discuss whats good and bad
JDBC Adapters appear to be a work in progress.
Even if there is no specific adapter available, remember that Spring Integration is a thin wrapper around POJOs. You'll be able to access JDBC in any component e.g. your service activators.
See here for a solution based on a polling inbound channel adapter too.