Add ServiceUsage utility and OSGiServiceInjector test-rule

.gitmodules

@@ -1,4 +1,4 @@
 [submodule "m2e-core-tests"]
 	path = m2e-core-tests
-	url = https://github.com/tesla/m2e-core-tests.git
-	branch = master
+	url = https://github.com/HannesWell/m2e-core-tests.git
+	branch = serviceUtilities

org.eclipse.m2e.core.tests/src/org/eclipse/m2e/core/MavenBugsTest.java

@@ -26,7 +26,8 @@
 import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.FileLocator;
 import org.eclipse.core.runtime.NullProgressMonitor;
-import org.eclipse.m2e.core.internal.MavenPluginActivator;
+import org.eclipse.m2e.core.internal.M2EUtils;
+import org.eclipse.m2e.core.internal.project.registry.MavenProjectManager;
 import org.eclipse.m2e.core.project.IMavenProjectFacade;
 import org.eclipse.m2e.core.project.MavenProjectInfo;
 import org.eclipse.m2e.core.project.ProjectImportConfiguration;
@@ -86,8 +87,8 @@ public void testMNG6530() throws Exception {
 	public void testMultiModuleProjectDirectoryChild() throws Exception {
 		IProject project = createExisting("simple", "resources/projects/dotMvn/", false);
 		waitForJobsToComplete(monitor);
-		IMavenProjectFacade facade = MavenPluginActivator.getDefault().getMavenProjectManagerImpl().create(project.getFile("child/pom.xml"),
-			true, monitor);
+		IMavenProjectFacade facade = M2EUtils.useService(MavenProjectManager.class,
+				m -> m.create(project.getFile("child/pom.xml"), true, monitor));
 		Assert.assertNotNull(facade);
 		File[] multiModuleDirectory = new File[] { null }; 
 		facade.createExecutionContext().execute((context, monitor) -> multiModuleDirectory[0] = context.getExecutionRequest().getMultiModuleProjectDirectory(), null);

org.eclipse.m2e.core.tests/src/org/eclipse/m2e/core/internal/project/registry/RegistryTest.java

@@ -23,6 +23,8 @@
 import java.util.Collections;
 import java.util.Optional;
 
+import javax.inject.Inject;
+
 import org.eclipse.core.resources.IFile;
 import org.eclipse.core.resources.IMarker;
 import org.eclipse.core.resources.IProject;
@@ -31,40 +33,46 @@
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.m2e.core.embedder.ArtifactKey;
-import org.eclipse.m2e.core.internal.MavenPluginActivator;
+import org.eclipse.m2e.core.internal.M2EUtils;
 import org.eclipse.m2e.core.project.IMavenProjectFacade;
 import org.eclipse.m2e.core.project.MavenUpdateRequest;
 import org.eclipse.m2e.core.project.ProjectImportConfiguration;
 import org.eclipse.m2e.tests.common.AbstractMavenProjectTestCase;
+import org.eclipse.m2e.tests.common.OSGiServiceInjector;
 import org.junit.Assert;
 import org.junit.Ignore;
+import org.junit.Rule;
 import org.junit.Test;
 
 
 public class RegistryTest extends AbstractMavenProjectTestCase {
 
+	@Rule
+	public OSGiServiceInjector serviceInjector = OSGiServiceInjector.INSTANCE;
+
+	@Inject
+	private ProjectRegistryManager projectRegistryManager;
+
   @Test
   public void testDeletedFacadeIsRemoved() throws IOException, CoreException, InterruptedException {
     IProject project = createExisting(getClass().getSimpleName(), "resources/projects/simplePomOK", true);
     waitForJobsToComplete(monitor);
-    IMavenProjectFacade facade = MavenPluginActivator.getDefault().getMavenProjectManagerImpl().create(project,
-        monitor);
+	IMavenProjectFacade facade = projectRegistryManager.create(project, monitor);
     Assert.assertNotNull(facade);
     project.delete(true, monitor);
     waitForJobsToComplete(new NullProgressMonitor());
     Assert.assertTrue(facade.isStale());
     project = createExisting(getClass().getSimpleName(), "resources/projects/emptyPom", true);
     waitForJobsToComplete(monitor);
-    facade = MavenPluginActivator.getDefault().getMavenProjectManagerImpl().create(project, monitor);
+    facade = projectRegistryManager.create(project, monitor);
     Assert.assertNull(facade);
   }
 
   @Test
   public void testMissingParentCapabilityStored() throws IOException, CoreException, InterruptedException {
     IProject project = createExisting(getClass().getSimpleName(), "resources/projects/missingParent", true);
     waitForJobsToComplete(monitor);
-    MutableProjectRegistry registry = MavenPluginActivator.getDefault().getMavenProjectManagerImpl()
-        .newMutableProjectRegistry();
+	MutableProjectRegistry registry = projectRegistryManager.newMutableProjectRegistry();
     MavenCapability parentCapability = MavenCapability
         .createMavenParent(new ArtifactKey("missingGroup", "missingArtifactId", "1", null));
     assertEquals(Collections.singleton(project.getFile("pom.xml")), registry.getDependents(parentCapability, false));
@@ -75,14 +83,13 @@ public void testMultiRefreshKeepsCapabilities() throws IOException, CoreExceptio
     IProject dependentProject = createExisting("dependent", "resources/projects/dependency/dependent", true);
     IProject dependencyProject = createExisting("dependency", "resources/projects/dependency/dependency", true);
     waitForJobsToComplete(monitor);
-    ProjectRegistryManager registryManager = MavenPluginActivator.getDefault().getMavenProjectManagerImpl();
-    Collection<IFile> pomFiles = new ArrayList<>(2);
+	Collection<IFile> pomFiles = new ArrayList<>(2);
     pomFiles.add(dependentProject.getFile("pom.xml"));
     pomFiles.add(dependencyProject.getFile("pom.xml"));
-    MutableProjectRegistry state = MavenPluginActivator.getDefault().getMavenProjectManagerImpl().newMutableProjectRegistry();
+    MutableProjectRegistry state = projectRegistryManager.newMutableProjectRegistry();
     state.clear();
-    registryManager.getMaven().execute(false, false, (context, aMonitor) -> {
-      registryManager.refresh(state, pomFiles, aMonitor);
+    projectRegistryManager.getMaven().execute(false, false, (context, aMonitor) -> {
+      projectRegistryManager.refresh(state, pomFiles, aMonitor);
       return null;
     }, monitor);
     Assert.assertNotEquals(Collections.emptyMap(), state.requiredCapabilities);
@@ -115,7 +122,9 @@ public void testResolvedParentConfiguration() throws Exception {
         request.addPomFile(parent.getFile("pom.xml"));
         IFile childPom = child.getFile("pom.xml");
         request.addPomFile(childPom);
-        MavenPluginActivator.getDefault().getProjectManagerRefreshJob().refresh(request);
+		try (var refreshJob = M2EUtils.useService(ProjectRegistryRefreshJob.class)) {
+			refreshJob.get().refresh(request);
+		}
         waitForJobsToComplete();
         IMarker[] markers = childPom.findMarkers(IMarker.PROBLEM, true, IResource.DEPTH_INFINITE);
         assertArrayEquals(new IMarker[0], markers);

org.eclipse.m2e.core.ui/src/org/eclipse/m2e/core/ui/internal/preferences/launch/MavenInstallationsPreferencePage.java

@@ -48,7 +48,8 @@
 import org.eclipse.m2e.core.MavenPlugin;
 import org.eclipse.m2e.core.embedder.IMaven;
 import org.eclipse.m2e.core.embedder.IMavenConfiguration;
-import org.eclipse.m2e.core.internal.MavenPluginActivator;
+import org.eclipse.m2e.core.internal.M2EUtils;
+import org.eclipse.m2e.core.internal.M2EUtils.ServiceUsage;
 import org.eclipse.m2e.core.internal.launch.AbstractMavenRuntime;
 import org.eclipse.m2e.core.internal.launch.MavenRuntimeManagerImpl;
 import org.eclipse.m2e.core.ui.internal.Messages;
@@ -62,6 +63,8 @@
 @SuppressWarnings("restriction")
 public class MavenInstallationsPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {
 
+  final ServiceUsage<MavenRuntimeManagerImpl> runtimeManagerUsage;
+
   final MavenRuntimeManagerImpl runtimeManager;
 
   final IMavenConfiguration mavenConfiguration;
@@ -76,8 +79,8 @@ public class MavenInstallationsPreferencePage extends PreferencePage implements
 
   public MavenInstallationsPreferencePage() {
     setTitle(Messages.MavenInstallationsPreferencePage_title);
-
-    this.runtimeManager = MavenPluginActivator.getDefault().getMavenRuntimeManager();
+    this.runtimeManagerUsage = M2EUtils.useService(MavenRuntimeManagerImpl.class);
+    this.runtimeManager = runtimeManagerUsage.get();
     this.mavenConfiguration = MavenPlugin.getMavenConfiguration();
     this.maven = MavenPlugin.getMaven();
   }
@@ -105,6 +108,12 @@ public boolean performOk() {
     return true;
   }
 
+  @Override
+  public void dispose() {
+    runtimeManagerUsage.close();
+    super.dispose();
+  }
+
   @Override
   protected Control createContents(Composite parent) {
 

org.eclipse.m2e.core.ui/src/org/eclipse/m2e/core/ui/internal/wizards/MavenPomSelectionComponent.java

@@ -64,7 +64,7 @@
 import org.eclipse.m2e.core.MavenPlugin;
 import org.eclipse.m2e.core.embedder.ArtifactKey;
 import org.eclipse.m2e.core.internal.IMavenConstants;
-import org.eclipse.m2e.core.internal.MavenPluginActivator;
+import org.eclipse.m2e.core.internal.M2EUtils;
 import org.eclipse.m2e.core.internal.index.IIndex;
 import org.eclipse.m2e.core.internal.index.IndexedArtifact;
 import org.eclipse.m2e.core.internal.index.IndexedArtifactFile;
@@ -256,14 +256,14 @@ public void init(String queryText, String queryType, IProject project, Set<Artif
       if(!selection.isEmpty()) {
         List<IndexedArtifactFile> files = getSelectedIndexedArtifactFiles(selection);
 
-        ArtifactFilterManager filterManager = MavenPluginActivator.getDefault().getArifactFilterManager();
-
-        for(IndexedArtifactFile file : files) {
-          ArtifactKey key = file.getAdapter(ArtifactKey.class);
-          IStatus status = filterManager.filter(MavenPomSelectionComponent.this.project, key);
-          if(!status.isOK()) {
-            setStatus(IStatus.ERROR, status.getMessage());
-            return; // TODO not nice to exit method like this
+        try (var filterManager = M2EUtils.useService(ArtifactFilterManager.class)) {
+          for(IndexedArtifactFile file : files) {
+            ArtifactKey key = file.getAdapter(ArtifactKey.class);
+            IStatus status = filterManager.get().filter(MavenPomSelectionComponent.this.project, key);
+            if(!status.isOK()) {
+              setStatus(IStatus.ERROR, status.getMessage());
+              return; // TODO not nice to exit method like this
+            }
           }
         }
 

org.eclipse.m2e.core/src/org/eclipse/m2e/core/internal/M2EUtils.java

@@ -14,12 +14,20 @@
 package org.eclipse.m2e.core.internal;
 
 import java.io.File;
+import java.lang.StackWalker.Option;
 import java.util.Collection;
 import java.util.ConcurrentModificationException;
 import java.util.HashSet;
+import java.util.NoSuchElementException;
 import java.util.Properties;
 import java.util.Set;
 import java.util.Stack;
+import java.util.function.Function;
+import java.util.function.Supplier;
+
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.FrameworkUtil;
+import org.osgi.framework.ServiceReference;
 
 import org.eclipse.core.resources.IContainer;
 import org.eclipse.core.resources.IFile;
@@ -170,4 +178,73 @@ public static void copyProperties(Properties to, Properties from) {
       }
     }
   }
+
+  public interface ServiceUsage<T> extends AutoCloseable, Supplier<T> {
+    @Override
+    void close(); // do not throw checked exception
+
+    boolean isAvailable();
+  }
+
+  private static final StackWalker WALKER = StackWalker.getInstance(Option.RETAIN_CLASS_REFERENCE);
+
+  public static <T> ServiceUsage<T> useService(Class<T> serviceClass) {
+    Class<?> callerClass = WALKER.getCallerClass();
+    BundleContext ctx = FrameworkUtil.getBundle(callerClass).getBundleContext();
+    return useService(serviceClass, ctx);
+  }
+
+  public static <T, R> R useService(Class<T> serviceClass, Function<T, R> function) {
+    Class<?> callerClass = WALKER.getCallerClass();
+    BundleContext ctx = FrameworkUtil.getBundle(callerClass).getBundleContext();
+    try (var service = useService(serviceClass, ctx)) {
+      return function.apply(service.get());
+    }
+  }
+
+  private static <T> ServiceUsage<T> useService(Class<T> serviceClass, BundleContext ctx) {
+    ServiceReference<T> reference = ctx != null ? ctx.getServiceReference(serviceClass) : null;
+    return useService(serviceClass, reference, ctx);
+  }
+
+  private static <T> ServiceUsage<T> useService(Class<T> serviceClass, ServiceReference<T> reference,
+      BundleContext ctx) {
+    T service = reference != null ? ctx.getService(reference) : null;
+    return service == null ? getUnavailableServiceUsage(serviceClass.getName()) : new ServiceUsage<>() {
+      @Override
+      public T get() {
+        return service;
+      }
+
+      @Override
+      public boolean isAvailable() {
+        return true;
+      }
+
+      @Override
+      public void close() {
+        ctx.ungetService(reference);
+      }
+    };
+  }
+
+  private static <T> ServiceUsage<T> getUnavailableServiceUsage(String serviceName) {
+    return new ServiceUsage<>() {
+
+      @Override
+      public boolean isAvailable() {
+        return false;
+      }
+
+      @Override
+      public T get() {
+        throw new NoSuchElementException("Service '" + serviceName + "' is not available"); //$NON-NLS-1$ //$NON-NLS-2$
+      }
+
+      @Override
+      public void close() { // nothing to do
+      }
+    };
+  }
+
 }

org.eclipse.m2e.core/src/org/eclipse/m2e/core/internal/MavenPluginActivator.java

@@ -59,12 +59,9 @@
 import org.eclipse.m2e.core.embedder.MavenModelManager;
 import org.eclipse.m2e.core.internal.archetype.ArchetypeCatalogFactory;
 import org.eclipse.m2e.core.internal.archetype.ArchetypeManager;
-import org.eclipse.m2e.core.internal.index.filter.ArtifactFilterManager;
-import org.eclipse.m2e.core.internal.launch.MavenRuntimeManagerImpl;
 import org.eclipse.m2e.core.internal.lifecyclemapping.LifecycleMappingFactory;
 import org.eclipse.m2e.core.internal.markers.IMavenMarkerManager;
 import org.eclipse.m2e.core.internal.project.registry.ProjectRegistryManager;
-import org.eclipse.m2e.core.internal.project.registry.ProjectRegistryRefreshJob;
 import org.eclipse.m2e.core.project.IMavenProjectRegistry;
 import org.eclipse.m2e.core.project.IProjectConfigurationManager;
 import org.eclipse.m2e.core.project.IWorkspaceClassifierResolverManager;
@@ -217,10 +214,6 @@ public ProjectRegistryManager getMavenProjectManagerImpl() {
     return getService(ProjectRegistryManager.class);
   }
 
-  public MavenRuntimeManagerImpl getMavenRuntimeManager() {
-    return getService(MavenRuntimeManagerImpl.class);
-  }
-
   public ArchetypeManager getArchetypeManager() {
     synchronized(this) {
       if(this.archetypeManager == null) {
@@ -258,11 +251,6 @@ public IProjectConfigurationManager getProjectConfigurationManager() {
     return getService(IProjectConfigurationManager.class);
   }
 
-  /** for use by unit tests */
-  public ProjectRegistryRefreshJob getProjectManagerRefreshJob() {
-    return getService(ProjectRegistryRefreshJob.class);
-  }
-
   public static String getVersion() {
     return plugin.version;
   }
@@ -283,10 +271,6 @@ public RepositorySystem getRepositorySystem() throws CoreException {
     return getMaven().lookup(RepositorySystem.class);
   }
 
-  public ArtifactFilterManager getArifactFilterManager() {
-    return getService(ArtifactFilterManager.class);
-  }
-
   /**
    * @return
    */

org.eclipse.m2e.launching/src/org/eclipse/m2e/internal/launch/MavenLaunchUtils.java

@@ -27,7 +27,7 @@
 
 import org.eclipse.m2e.actions.MavenLaunchConstants;
 import org.eclipse.m2e.core.internal.Bundles;
-import org.eclipse.m2e.core.internal.MavenPluginActivator;
+import org.eclipse.m2e.core.internal.M2EUtils;
 import org.eclipse.m2e.core.internal.launch.AbstractMavenRuntime;
 import org.eclipse.m2e.core.internal.launch.MavenRuntimeManagerImpl;
 import org.eclipse.m2e.workspace.WorkspaceState;
@@ -44,9 +44,8 @@ private MavenLaunchUtils() { // static use only
   }
 
   public static AbstractMavenRuntime getMavenRuntime(ILaunchConfiguration configuration) throws CoreException {
-    MavenRuntimeManagerImpl runtimeManager = MavenPluginActivator.getDefault().getMavenRuntimeManager();
     String name = configuration.getAttribute(MavenLaunchConstants.ATTR_RUNTIME, ""); //$NON-NLS-1$
-    AbstractMavenRuntime runtime = runtimeManager.getRuntime(name);
+    AbstractMavenRuntime runtime = M2EUtils.useService(MavenRuntimeManagerImpl.class, rm -> rm.getRuntime(name));
     if(runtime == null) {
       throw new CoreException(new Status(IStatus.ERROR, MavenLaunchConstants.PLUGIN_ID, -1, //
           NLS.bind(Messages.MavenLaunchUtils_error_no_maven_install, name), null));