How to integrate the spring boot project generated by swagger with OSGi and deploy it in Apache karaf?
How should I write my pom.xml and how to modify the startup class. If there is something not detailed, I will add it. Thank you!
You don't. It's not strictly impossible but it would be a lot of work and struggle and you will not get any benefits out of it.
If you want SpringBoot - stick to that. You will sacrifice modularity, strong encapsulation, enforced clean architecture and bunch of other architectural thing that will matter a lot in the long run. But you will gain something that is easy to work with in the beginning and tons of code to copy/paste.
If you are playing the long game - I'd recommend to forget about SpringBoot and learn how to build modular OSGi applications. Recent version allow you to use popular technologies like JAX-RS and CDI. You can probably use one of the Swagger's JAX-RS generators and then convert the outcome to proper modular code. It may even be that there is a generator that generates OSGi JAX-RS code already.
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I do not wish to use Spring annotations or xml or any declarative, non-compile-time-safe code or anything that relies on reflection. However, I'm guessing Spring does have traditional libraries (like Apache Commons libraries) that you can call from your code rather than your annotated code getting called by the framework.
What Spring projects are libraries? I'm assuming some of them are.
The core of Spring is the Spring Framework. Which is uses reflection, annotations etc without remorse. Using spring as a library completely misses the point. You could use, say JdbcTemplates with the correct dependency but why?
If you do use Spring as a Library bare in mind you are only getting tiny bits of functionality, most of which is just bootstrap code you avoid writing. Spring is designed to be used within it's framework and built upon. Some do use libraries such as Apache Commons. Using Spring Framework as a library however does just complicate your own project and people would probably ask - "why".
Is it possible to use Ceylon classes in a Spring Boot application? What would that look like - the Ceylon classes as a separate dependency, or could they be in the same project?
I've got a particularly knotty Java problem that would really benefit from reified generics and an absence of type erasure. However, the main reason I'm writing it in Java in the first place is because I want to exploit a Java library for interacting with a thing. I don't want to learn any more Ceylon than is necessary for solving the problem, if at all possible.
Ceylon integration with java is really smooth, you can use all the springboot stack and use java classes and even libs (maven) without problems, I have a small project ceylon with springboot using Discovery, Gateway and microservices that you can use as example. Its not documented yet but if you know about springboot then I think its enough as start point for you. I hope it's enough , otherwise I am available to help.
Its working/using ceylon from current development, I didnt try with 1.2.2 release.
This question already has answers here:
When is it necessary or convenient to use Spring or EJB3 or all of them together?
(2 answers)
Closed 6 years ago.
I am currently preparing my final project study. I have to develop a distributed application for the management of human resources, but on my benchmark for technologies to use I found it confusing to decide between Spring or the EJB 3.1.
I do not know which will be the best suitable and easiest to use. I am a beginner for both technologies and therefore I hope so someone can help me.
You do not choose between EJB and Spring, you actually choose between Java EE and Spring because EJB is only a part of Java EE which includes also other components like JMS, Servlets, JSP, JSF, CDI, etc. In its early days (J2EE 1.4) programming model of enterprise edition of Java had a lot of flaws and deficiencies, but the most important ones were that it was tedious and verbose with a lot of boiler-plate code and tons of xml configurations. Spring was introduced as an alternative framework favoring convention-over-configuration principle. In other words, in Spring there were some sensible defaults that could be reconfigured if you need it. Java EE 5 introduced significant changes adopting the same convention-over-configuration principle from Spring, drastically reducing code amount and complexity required to get things going, so in this area Spring does not hold any sensible advantage any more.
It is also important to bear in mind that Java EE is just a specification. To build a real world app you need an implementation and there are plenty of them today - Glassfish, JBoss, TomcatEE, etc. all provide different implementations of Java EE specification introducing additional complexity - I mean, now you have to choose which Java EE implementation to choose. You can contrast that with Spring which comes from a single source.
Both frameworks gives you pretty much similar functionality. All support transactions, ORM, provide tools for building business logic, support CDI, AOP. In both Spring and Java EE you can only use the parts that you need, in other words you don't have to use the whole framework. You can even use them together - they can interoperate. Thanks to introduction of embeddable containers you now can even use Java EE features you need in areas like desktop applications which traditionally were the realm of Spring.
But one area where Java EE still lacks behind Spring is comfortable testability. It is not easy to write unit tests for EJB - for this you have to use a special third-party framework (Arquillian) and write some boilerplate code inside your tests (e.g. for building the test deployment package and deploying it onto the container, etc.). In fact, Java EE lacks any support for testing EJBs out of the box. In contrast, Spring is built with testability and TDD in mind. Testing Spring beans is easy since Spring includes bundled support for both testing (unit testing, integration testing) of all parts of the application as well as mocking.
I have a Spring3 application which takes about 3 minutes to load a big domain model on startup... this is fine when the application is deployed to a production environment every once in a while but its a massive pain when making development changes due to the stopping/starting of the application.
I've done a bit of investigation and I like the idea of separating my application in modules using OSGi so that I can deploy only the parts of my application which are changing (e.g. No need to deploy the Domain Model when I'm making changes to the Persistence layer); However I've found the barrier to entry for OSGi to be quite high.
Is it possible to use both Blueprint to inject the services provided between modules (e.g to expose implementations of the domain model to my web tier) and to continue to use the Spring framework (not Spring Dynamic Modules) inside each of my modules?
You can not mix blueprint and spring. They are two separate technologies that are similar but incompatible.
I would also not recommend using spring dm in OSGi. While it works for some simple cases it has a horrible classloading model that leads to massive problems in OSGi. See this article from Guillaume Nodet. Besides that spring dm was abandoned by springsource. There are not even bug fixes since ages.
Spring Gemini is also practically abandoned. Springsource donated it to eclipse and then ceased to really work on it.
So if you want to go this step to OSGi you will have to switch to aries blueprint or to declarative services. So do not underestimate the effort.
Is the any way to perform integration CQ5 platform with Spring framework?
I would like to use Spring IoC capabilities to make my code more clear and efficient.
UPDATE
Hello againg, seems that I found solution.
Guys here developed Slice framework that really redices amound of code and made CQ5 development easier.
You probably want to check out Eclipse Gemini Blueprint, or it's original incarnation Spring Dynamic Modules. The Blueprint project basically gives you an easy way to create Spring enabled bundles in an OSGi environment.
As shsteimer mentions, Spring distributions before 3.2.0 were OSGi bundles, so could be dropped into an OSGi environment and you could probably use them directly. Spring 3.2.0 bundles and above are now available through the SpringSource ERB. However, Blueprint gets around or helps with some of the boilerplate OSGi stuff that you would otherwise have to do.
On a past project, I was able to get Spring JDBC working inside of CQ (to support some legacy code so we didn't have to re-write it). My memory is that the spring jar files already come "OSGI-ified" and so it was just a matter of figuring out all the layers of dependency needed for JDBC to work inside of CQ, and adding all the jars to the repository in an /apps/myApp/install folder.
Long story short, I'm not sure about IoC, but you might check to see if it's already packaged as an OSGI version which you can simply use without too much hassle.