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Using Spring #PropertySource in a Maven submodule

In a Spring-boot application, I was having a single module and I was able to inject a configuration file, e.g. "my.properties", that was located in src/main/resources as follows:
#Configuration
#PropertySource("/my.properties")
public class MyConf{
}
Everything was ok, but then I created submodules and now I moved that configuration file in a submodule. When I start the main application I gedt the following exception:
org.springframework.beans.factory.BeanDefinitionStoreException: Failed to parse configuration class [com.myapp.MainApplication]; nested exception is java.io.FileNotFoundException: Could not open ServletContext resource [/home/jeanvaljean/workspace/mainmodule/secondarymodule/my.properties]
As I see, I can solve the issue by writing
#PropertySource("/src/main/resources/my.properties")
Doing this, the path is correct and the file can be loaded.
Anyway, that is an horrible solution, and I'm pretty sure that there is a more elegant and flexible alternative. Any solution?

Spring has a few different implementations of how to find a resource. By using the prefix classpath: you are telling Spring to search for the resource in all the classpath, rather than in the classes that are bundled with your application.
Depending on the ApplicationContenxt, Spring will use a different default Resource class. It looks like in your case, Spring was instantiating a FileSystemResource, which only finds files available on the filesystem with either relative or absolute paths (but not inside jars!). My rule of thumb is to never prefix something if it's in the same module/component/jar, and always prefix it with classpath: if I know it's in a different module/component/jar (some people get mad at this :).
You can read a more in the Spring Documentation - Resources

Loading the same properties(yml) files in testing enviornment?

I am trying to figure out whether I can load the same .yml property files in testing environment as I load in real.
For example I have a test:
\src\test\java\security\TokenTest.java
Annotated with:
#RunWith(SpringJUnit4ClassRunner.class)
#SpringApplicationConfiguration(classes = Application.class)
#WebAppConfiguration
#DirtiesContext(classMode = DirtiesContext.ClassMode.AFTER_EACH_TEST_METHOD)
#ActiveProfiles("dev")
Then I have:
\src\main\resources\application.yml
When I run the application, the environment picks up property-source from the yml location.
Whenever I run my test, the environment does not see this file - i.e. property-source is not created/populated.
The obvious solution is to put duplicate file to the test location:
\src\test\resources\application.yml
And it will load, but that is bad - in terms that it raises unnecessary confusion when perceiving the difference between test and main resources.
This previous problem gets enhanced if you have configuration file per environment.
Is there a way to load resources from src/main/resources for tests?
This is probably some basic classpath scanning concept which I don't know.
My case is that I already faced the nightmare when you have 5 yml properties files per enviornment in src/main/resources and then you have 5 corresponding yml properties files in src/test/resources and someone from your team WILL 100 % at some point introduce discrepancy between them making everyone else bleed in the long term.
So by any means tests must refer to the same configuration files not to be the lost within its own void context.
Solution: Try to "rebuild" the project.

Is there a way to load resources from src/main/resources for tests?
It works for me. Maybe your IDE is not copying changes to the output directory on save or something (I have heard IntelliJ users have to switch that feature on)?

I had the same problem as you, but I figured out that it was a classpath problem in my run configuration in intellij, when setting that up like it should have been it worked as a charm loading application.yml from the main/resources.

Spring Maven unitTest applicationContext loading wrong file

.I have a project that has a spring-config.xml file in src/main/webapp/WEB-INF and an applicationContext.xml file in src/test/resources. I also have an abstract test base class for my unit tests in src/test/java looks something like:
#ContextConfiguration(locations = {"classpath:/applicationContext.xml"})
public abstract class AbstractTestBase extends AbstractTransactionalJUnit4SpringContextTests {
//Common code and fields
}
All my unit tests extends this AbstractTestBase which points to the context within the src/test/resources or should. The problem arises when running my unit tests it is pulling in the spring-config.xml file.
There are other projects my team is working on that have the same file structure, same app context setup, and run as intended, but even when I have each file in the project side by side I don't see where their file runs and this one doesn't.
I am new to spring so I don't know what it is I should be looking for.
Are there any situations where Spring or Maven would not take the app context I'm handing it given all files exist? Is there anything I might be missing?
EDIT: corrected to reflect that one file is a spring-config file.

"classpath:/applicationContext.xml" should look under src/test/resources.
But it should be noticed that using that syntax will load the first one it finds and then stop as mentioned by '#chrylis'.
I once had similar problem.
You must have been using an IDE. There must have been applicationContext.xml file in your target/test-classes/ (in Eclipse IDE) in your project directory that is a copy of your xml file under src/main/webapp/WEB-INF or xml file like it.

Output classpath content from within Spring context configuration

Does Spring provide any way to output the actual content of the classpath environment variable when it is loading a resource in a context configuration file?
<!-- Import the special context -->
<import resource="classpath:mySpecialApplicationContext.xml"/>
I set the Log4J logging level to ALL for Springframework classes but this value does not appear to be logged by the framework. I am trying to figure out if Spring is loading this from a dependency, and I want to see the classpath setting during application runtime. The application is built by Maven with many dependencies.
If there are two or more mySpecialApplicationContext.xml's in the classpath, which one does Spring use?
Thank you.

You can see the relevant (I think) source code at http://goo.gl/9dK2c
In short:
No, the classpath is not logged
The details of what would be loaded when there is more than one matching resource in the classpath are ClassLoader dependent - the DefaultResourceLoader uses the thread's classloader, but typically, the first one found would be used.

Spring Dependency Injection and Plugin Jar

I have web application running with a default impl of a backend service. One should be able to implement the interface and drop the jar into the plugins folder (which is not in the apps classpath). Once the server is restarted, the idea is to load the new jar into the classloader, and have it take part in dependency injection. I am using Spring DI using #Autowired. The new plugin service impl will have #Primary annotation. So given two impls of the interface, the primary should be loaded.
I got the jar loaded into the classloader and can invoke the impl manually. But I haven't been able to get to to participate in the Dependency Injection, and have it replace the default impl.
Here's a simplified example:
#Controller
public class MyController {
#Autowired
Service service;
}
//default.jar
#Service
DefaultService implements Service {
public void print() {
System.out.println("printing DefaultService.print()");
}
}
//plugin.jar not in classpath yet
#Service
#Primary
MyNewService implements Service {
public void print() {
System.out.println("printing MyNewService.print()");
}
}
//For lack of better place, I loaded the plugin jar from the ContextListener
public class PluginContextLoaderListener extends org.springframework.web.context.ContextLoaderListener {
#Override
protected void customizeContext(ServletContext servletContext,
ConfigurableWebApplicationContext wac) {
System.out.println("Init Plugin");
PluginManager pluginManager = PluginManagerFactory.createPluginManager("plugins");
pluginManager.init();
//Prints the MyNewService.print() method
Service service = (Service) pluginManager.getService("service");
service.print();
}
}
<listener>
<listener-class>com.plugin.PluginContextLoaderListener</listener-class>
</listener>
Even after I have loaded the jar into the classloader, DefaultService is still being injected as service. Any idea how I get the plugin jar to participate into the spring's DI lifecycle?
Edited:
To put it simply, I have a war file that has a few plugin jars in a plugins directory inside the war. Based on a value from a configuration file that the app looks at, when the app is started, I want to load that particular plugin jar and run the application with it. That way, I can distribute the war to anyone, and they can choose which plugin to run based on a config value without having to to repackage everything. This is the problem I am trying to solve.

It seems like all You need is to create the Spring ApplicationContext properly. I think it's possible without classpath mingling. What matters most are the locations of the Spring configuration files within the classpath. So put all Your plugin jar's into WEB-INF/lib and read on.
Let's start with the core module. We'll make it to create it's ApplicationContext from files located at classpath*:META-INF/spring/*-corecontext.xml.
Now we'll make all plugins to have their config files elsewhere. I.e. 'myplugin1' will have its config location like this: classpath*:META-INF/spring/*-myplugin1context.xml. And anotherplugin will have the configs at classpath*:META-INF/spring/*-anotherplugincontext.xml.
What You see is a convension. You can also use subdirectiries if You like:
core: classpath*:META-INF/spring/core/*.xml
myplugin1: classpath*:META-INF/spring/myplugin1/*.xml
anotherplugin: classpath*:META-INF/spring/anotherplugin/*.xml
What matters is that the locations have to be disjoint.
All that remains is to pass the right locations to the ApplicationContext creator. For web applications the right place for this would be to extend the ContextLoaderListener and override the method customizeContext(ServletContext, ConfigurableWebApplicationContext).
All that remains is to read Your config file (its location can be passed as servlet init parameter). Than You need to construct the list of config locations:
String locationPrefix = "classpath*:META-INF/spring/";
String locationSiffix = "/*.xml";
List<String> configLocations = new ArrayList<String>();
configLocations.add(locationPrefix + "core" + locationSiffix);
List<String> pluginsTurnedOn = getPluginsTurnedOnFromConfiguration();
for (String pluginName : pluginsTurnedOn) {
configLocations.add(locationPrefix + pluginName + locationSiffix);
}
applicationContext.setConfigLocations(configLocations.toArray(new String[configLocations.size()]));
This way You can easily manage what is and what is not loaded into Spring ApplicationContext.
Update:
To make it work there's one more hidden assumption I made that I'm about to explain now. The base package of the core module and each plugin should also be disjoint. That is i.e.:
com.mycompany.myapp.core
com.mycompany.myapp.myplugin1
com.mycompany.myapp.anotherplugin
This way each module can use <context:componet-scan /> (on equivalent in JavaConfig) easily to add classpath scanning for it's own classes only. The core module should not contain any package scanning of any plugin packages. The plugins should extend configuration of ApplicationContext to add their own packages to classpath scanning.

If you restart the server, I see no reason why you can't just add the JAR to the WEB-INF/lib and have it in the CLASSPATH. All the complication of a custom class loader and context listener goes away, because you treat it just like any other class under Spring's control.
If you do it this way because you don't want to open or modify a WAR, why not put it in the server /lib directory? Let the server class loader pick it up. This makes all plugin classes available to all deployed apps.
The answer depends on how important the separate /plugin directory is. If it's key to the solution, and you can't add the JAR to the server's /lib directory, then that's that. I've got nothing. But I think it'd be worthwhile to at least revisit the solution you have to make sure that it's the only way to accomplish what you want.