Is it possible to take a project that I've been working on , import it into Spring STS and apply all the goodies that STS provides for easy Spring development to the project? For example, I'd like to be able to take this existing project which is not a Spring MVC application at the moment and treat it as though it was created as a Spring MVC template (kind of like wrapping the project in an STS MVC template). I hope this makes sense :)
As far as I am aware you can't decorate an existing project with Spring goodies just by importing it in to STS.
The best you can do is import and add the Spring project nature. This can be found by right-clicking on the project and selecting Spring Tools --> Add Spring Project nature.
Related
I have a large application with a database, Swing UI etc. Now I want to add a REST API for this application. Spring Boot allows easy generation of a REST API with useful features such as OpenApi documentation and authentication.
However when I run the Spring Boot application from within the large non Spring Boot application the Spring Boot application gets confused by the dependencies of the parent application and fails to run.
So my requirement is this: run a Spring Boot application from withing a non Spring Boot application without dependency interference from the parent application. I am currently running the Spring Boot application by adding the executable jar as a dependency and then calling
org.springframework.boot.loader.JarLauncher.main(new String[0]);
to run the Spring Boot application. I am not set on this way of doing it and any suggestions will be greatly appreciated.
Spring is a huge collection of highly configurable software libraries that can be used to setup (among other things) REST API endpoints and OpenAPI documentation and UI.
Spring Boot is a project to simplify the process of using these libraries by applying an opinionated view of how to run them within a standalone process.
By asking how to run a Spring Boot application within a larger application you are trying to get the benefit of the opinionated setup while violating the assumptions that the setup is based on. I guess in theory it might be possible using some sort of handrolled classloader isolation, but once you've solved the dependency problem you'll probably end up with class version conflicts, issues with configuration locations, etc. In short if it is possible at all the effort of doing so would negate the benefit.
There are two ways of resolving the issue.
Use Spring Boot to build your API as a standalone process. Configure the new process to talk to the same database as the existing application. If neccessary factor out any code common to both the existing application and the API (JPA entities, DAO classes etc) into a shared library. If you go with this option you will have the overhead of having to manage multiple kinds of process in your production environment, which is more complex - but has advantages in terms of decoupling scaling, release cycles, restart times. See the debate on microservices (https://martinfowler.com/articles/microservices.html).
Use the Spring libraries that provide REST and OpenAPI features as part of your existing application, without using Spring Boot. You'll need to have SpringMVC set up in order to use #RestController annotated classes. If your existing application is a web application that's not too bad (https://docs.spring.io/spring-framework/docs/3.2.x/spring-framework-reference/html/mvc.html). If it's not run in a webserver already you'll have to launch the SpringMVC framework in an embedded webserver (https://devcenter.heroku.com/articles/create-a-java-web-application-using-embedded-tomcat). There's a good article on adding OpenAPI to an MVC application here: https://www.baeldung.com/spring-rest-openapi-documentation.
you can simply exclude auto-configure dependencies. Here is an informative link https://www.marcobehler.com/guides/spring-boot
Here is a code snippet of how to exclude when applications get started.
#SpringBootApplication(exclude = {DataSourceAutoConfiguration.class)
public class Application {
public static void main(String[] args) {
SpringApplication.run(PayPalApplication.class, args);
}
}
or the other ways
spring.autoconfigure.exclude=org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration
I want to share another Spring Framework dependencies https://www.marcobehler.com/guides/spring-framework
Is there any way like eclipse plugin or something to generate Spring beans java classes automatically from a XML beans configuration file.
Or any similar kind of way. As I am doing a new project setup for REST API/ Spring/ Hibernate.
Thanks in advance.
Look at spring boot project starters. They can get you up and running quickly and there are many archetypes for common project requirements.
Please advise me a project where I can see how to use Spring MVC and Hibernate together in the right way. I'm new to these frameworks.
Appfuse has a Maven archetype for this stack.
Strongly suggest you have a peak.
Alternatively the book Spring in Action was a great resource for me in learning spring and hibernate/spring interaction - use Annotation driven transaction management as well and you have a really great start.
see here: http://appfuse.org/display/APF/Using+Spring+MVC
appfuse-basic-spring is the basic project archetype.
Using maven modules is a better practice. ie)
appfuse-modular-spring
If you install m2e (maven 2 eclipse plugin) creating a new maven project will allow you to select the archetype.
better answer:
If I was going to recommend HOW to learn these technologies, I would say learn how to build a hibernate/maven/xml project first by following this:
http://www.mkyong.com/hibernate/quick-start-maven-hibernate-mysql-example/
Then learn how to use spring for dependency injection with maven/hibernate and xml:
http://www.mkyong.com/spring/maven-spring-hibernate-mysql-example/
Take special note of layering of the bo/dao pattern and how you use interfaces but wire in implementations with spring di - this is crucial for writing quality code
Next check hibernate annotations and annotation driven transactions:
http://www.springbyexample.org/examples/hibernate-transaction-annotation-config.html
http://www.springbyexample.org/examples/hibernate-transaction-annotation-config-code-example.html
http://www.mkyong.com/hibernate/maven-hibernate-annonation-mysql-example/
Finally, you can learn your mvc framework of choice. I actually recommend struts2 but it won't matter much. use spring DI by implementing interfaces and wiring implementations at runtime for you actions/controller. If you don't understand this how, you will after the hibernate/spring tutorials. Spring in action will be a good reference to keep on your desk but will take a few weeks to digest as you learn. Good luck! You can do it - I did and am now working as a java dev!
the petclinic app includes these, and many more things
spring-roo can create a skeleton project using these technologies for you.
If you are new to Spring MVC and Hibernate, I advice you to follow the Spring MVC step by step guide. The only problem with this is the version, the guide uses version 2.5 and the current release is 3.1.x, but it's a very good starting point to accumulate knowledge.
Spring MVC quickstart archetype provide simple spring-mvc and hibernate configuration.
Can anybody tell me a basic configuration to use String dependency injection? What are the minimum required jars?
At the moment I'd like to use only Inversion Of Controll, maybe later I'll integrate ORM.
Thanks
Try Spring roo, there is nothing simpler than that to get a full fledged Spring based web application working, with all the dependencies wired together.
Spring STS (an Eclipse distribution customized for Spring available for free from SpringSource) contains several Spring project wizards that produce IoC enabled projects that you could use as examples.
Almost all Spring examples use Maven to define dependencies and download jars automatically from repositories available on the internet.
I am experimenting with Spring Roo in a new GWT application. The Spring Roo GWT support is some way off ready for real use just yet, so I want to build the GWT stuff by hand using as much of the GWT 2.1 MVP stuff as possible. The problem I have is that Spring Roo "notices" my MVP-related classes and generates a whole lot of extra (broken) stuff for my entities.
How can I get Spring Roo to ignore the GWT side of my project?
"I want to build the GWT stuff by hand using as much of the GWT 2.1 MVP stuff as possible"
If you're building GWT by hand, it sounds like you're interested in using Spring Roo to generate your data model code — but don't want (or need) any of Spring Roo's web controller code. If that's the case then you can separate your project into two modules:
A module containing model and persistence code that is created by Spring Roo
A GWT web application that you create by hand.
Make the first (Roo) module a dependency of the second (GWT) module. Basically you're using Roo to create a JAR library that's used by your web application. As long as you don't run the controller command the Roo won't add any web application code to your module.
I renamed my gwt.scaffold package to gwt.shell and gwt.request to gwt.req and Spring Roo is leaving my stuff alone.