Why Eclipse JUnit4 Runner does not receive META-INF / services files

Question

I am using Maven with Eclipse (using M2E) to create a project that relies on java.util.ServiceLoader to dynamically load some factory classes. It works fine when I run it in Maven, but when I run the test using the built-in Eclipse JUnit4 Runner, it cannot pick up the services and the tests fail.

Is there something I need to do to manually add META-INF / services to the JUnit build path? I could not get it to work either in src / main / resources / META-INF / services, or in src / main / java / META-INF / services. Is this related to how M2E sets the build path? I made a test in a completely new project, and it still failed.

Base code that doesn't work:

public class TestServiceLoader<S> { public TestServiceLoader(final Class<S> serviceClass) { ServiceLoader<S> serviceLoader = java.util.ServiceLoader.load(serviceClass, serviceClass.getClassLoader()); Iterator<S> services = serviceLoader.iterator(); if(!services.hasNext()) { throw new RuntimeException("Failed to get any services for this class"); } } } 

The test is as follows:

 @Test public final void testTestServiceLoader() { TestServiceLoader<TestFactory> serviceLoader = new TestServiceLoader<TestFactory>(TestFactory.class); } 

TestFactory is defined as:

 public interface TestFactory { } 

TestFactoryImpl is defined as:

 public class TestFactoryImpl implements TestFactory { } 

I originally used the MetaInfServices generator http://weblogs.java.net/blog/kohsuke/archive/2009/03/my_project_of_t.html , but when I deleted it and manually created the files manually, it still failed in the same way for Eclipse when it is executed at startup using the Maven Surefire plugin.

Answer 1

M2E developers believe that any resources will influence the maven assembly, even when META-INF / services / is a functional part, although the resource:

"Actually, the project resource folder really does not need to be added to the build path (Maven Builder will work without it), but it was considered convenient and looking better in the package explorer and other Eclipse views." Frequently Asked Questions M2E

If you want to hack it, you can apparently encode a special M2E profile in your pom.xml files to create an additional M2E build module and copy Sonata resources like the M2Eclipse Wiki