how to call a applet in spring control class?
Spring is mostly used on server-side, and applets - on client side. So I'd assume two scenarios:
you want to use spring in your applet - then simply ship the spring jars, the applicationContext.xml and start with instantiating ClassPathXmlApplicationContext for example.
you want to reuse functionality from an applet on the server side - in that case move that functionality to a helper class, and import it in both the applet and the spring beans.
Related
Let's say we have a Spring MVC project which is a banking web application. I am trying to identify the sub-systems ,modules and components of this project.
1.Subsystems - from what I have red the subsystems in MVC architecture are only 3- the Model,View and Controller is that correct?
2.Modules - are these a group of classes that do something particular as a group.For example LoginController.java,RegisterControler.java form a module let's call it Authentication
3.Components - for components I am not sure which they are in a Spring MVC project.
If someone can explain with examples in terms of a banking web application or other Spring MVC app it would be great!
Spring MVC follows the Model-View-Controller design pattern.
Model - A model contains the data of the application. A data can be a single object or a collection of objects.
Controller - A controller contains the business logic of an application. Here, the #Controller annotation is used to mark the class as the controller.
View - A view represents the provided information in a particular format. Generally, JSP+JSTL is used to create a view page. Although spring also supports other view technologies such as Apache Velocity, Thymeleaf and FreeMarker.
Spring Boot Framework has mainly four major Components.
Spring Boot Starters.
Spring Boot AutoConfigurator.
Spring Boot CLI.
Spring Boot Actuator.
Please check out : https://www.journaldev.com/7989/key-components-and-internals-of-spring-boot-framework
In project-specific terms,
Module: It can be something that can be built separately in an application. ex: Login Module, Sign-up module, Transactions module, etc., You can say a module is a group of components.
Sub-systems: As far as I know, subsystems are the service package related stuff.
Components: Annotating a class with #Component tells Spring that it is available for fulfilling injections.
Spring Component annotation is used to denote a class as a Component. It means that the Spring framework will autodetect these classes for dependency injection when annotation-based configuration and classpath scanning is used
I am looking for a feature that is similar to what #WebMvcTest does.
What #WebMvcTest does .
1. only instantiating the web layer, not the whole context
2. Only works with Spring Boot application (as it is in the package - org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest).
What I want to achieve
Write unit test case on Controller only instantiating the web layer, not the whole context on Spring MVC application (not Spring Boot application)?
Is there a way to achieve that?
I have a Spring Boot Jersey Application. I want to use a custom class loader with it to allow loading classes and resources from outside of standard web application classpath. (I need it to allow customers to add "plugins" to the application without disturbing original application file structure). Any suggestions how can I do that?
I have a web project, and I depoly it on tomcat easily. Infact I have a WebAppInitializer class that implements WebApplicationInitializer (this class it's really fat), as you know every application server that supports servlet 3.0, it can easily detect it and try to boot it. Now I wonder that it could be possible to use spring boot starter and without any further configuration, I pass my WebAppInitializer to it and spring boot based on my WebAppInitializer boots my project?
I just want to use the approach of spring-boot to deploy application on Tomcat and I don't want to use other spring-boot's facilities.
Yes, it's an old question. But I do not see an accepted answer and the one closest to a working one only has a link to an external resource. So here it is.
https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#boot-features-embedded-container-context-initializer
28.4.2 Servlet Context Initialization
Embedded servlet containers do not directly execute the Servlet 3.0+
javax.servlet.ServletContainerInitializer interface or Spring’s
org.springframework.web.WebApplicationInitializer interface. This is
an intentional design decision intended to reduce the risk that third
party libraries designed to run inside a war may break Spring Boot
applications.
If you need to perform servlet context initialization in a Spring Boot
application, you should register a bean that implements the
org.springframework.boot.web.servlet.ServletContextInitializer
interface. The single onStartup method provides access to the
ServletContext and, if necessary, can easily be used as an adapter to
an existing WebApplicationInitializer.
Scanning for Servlets, Filters, and listeners
When using an embedded
container, automatic registration of classes annotated with
#WebServlet, #WebFilter, and #WebListener can be enabled by using
#ServletComponentScan.
[Tip] #ServletComponentScan has no effect in a standalone container,
where the container’s built-in discovery mechanisms are used instead.
I've tried it. It works
In my use case I have project containing a few dozens of webapps, designed to run on Tomcat as WAR. Lots of logics was neatly crafted into WebApplicationInitializers and it seemed there should be an easier way to reuse all this. Adding implements ServletContextInitializer to those initializers and exposing them as beans through #Configuration classes lit my webservers up with SpringBoot's embedded Tomcat.
http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-create-a-deployable-war-file describes precisely how to do it
From the Spring Boot docs:
Servlet 3.0+ applications might translate pretty easily if they already use the Spring Servlet 3.0+ initializer support classes. Normally all the code from an existing WebApplicationInitializer can be moved into a SpringBootServletInitializer. If your existing application has more than one ApplicationContext (e.g. if it uses AbstractDispatcherServletInitializer) then you might be able to squash all your context sources into a single SpringApplication. The main complication you might encounter is if that doesn’t work and you need to maintain the context hierarchy. See the entry on building a hierarchy for examples. An existing parent context that contains web-specific features will usually need to be broken up so that all the ServletContextAware components are in the child context.
So yes, it's possible but you need to convert it to SpringBootServletInitializer, which seems to be quite similar.
We are developing a web application which uses spring mvc, rest, jquery, ajax and json. Also we use mongodb as our db. We use maven as build tool.
I have a project structure like below:
eem (parent pom)
eem-db (sub module, and it is a Eclipse project for mongo db dao level and model resides here)
eem-net (sub module, and it is again a Eclipse project for some networking code)
eem-webapp (sub module, and it is a Eclipse web app project for web application, which has Spring MVC)
My doubt is about the design of our web application in which I'm not knowing how to use spring container on this web app.
Below are my requirements and need help:
Is it a correct way to have mongodb related dao in a separate project?
(we use dependency on eem-webapp to get db code (as .jar) on our web app).
How can i use #Autowired on the model in my controller to get mongo db model "emp" (say, com.eem.db.model.emp)? i.e What configuration do i need to provide on my eem-webapp to autowire emp (and all model classes) model to my controller?
I want to instantiate a class (say, com.eem.net.discovery.discover) from eem-net on my controller. How should i do this from spring config file. I know using new is not necessary when we are on spring container. What kinda DI i should use for this situation?
Any pointers for my learning?
The best practique is create one session factory bean (scope=singleton) that you can #Autowired in all your Controllers, you can also create one pool connections to managing your clients db requests.
For this you can create your own .jar, and use your own .jar classes to register your bean in your spring container.