Lazy loading (and reloading) of project resources.

Change-Id: I4a725d523ae14ba8b487076e230fe9d622d5d281

9 files changed, 188 insertions, 127 deletions

diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/build/builders/PreCompilerBuilder.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/build/builders/PreCompilerBuilder.java
index 5183658bf..73d183cec 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/build/builders/PreCompilerBuilder.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/build/builders/PreCompilerBuilder.java
@@ -323,17 +323,22 @@ public class PreCompilerBuilder extends BaseBuilder {
 
                     // Notify the ResourceManager:
                     ResourceManager resManager = ResourceManager.getInstance();
-                    ProjectResources projectResources = resManager.getProjectResources(project);
 
                     if (ResourceManager.isAutoBuilding()) {
+                        ProjectResources projectResources = resManager.getProjectResources(project);
+
                         IdeScanningContext context = new IdeScanningContext(projectResources,
                                 project, true);
 
-                        resManager.processDelta(delta, context);
+                        boolean wasCleared = projectResources.ensureInitialized();
+
+                        if (!wasCleared) {
+                            resManager.processDelta(delta, context);
+                        }
 
                         // Check whether this project or its dependencies (libraries) have
                         // resources that need compilation
-                        if (context.needsFullAapt()) {
+                        if (wasCleared || context.needsFullAapt()) {
                             mMustCompileResources = true;
 
                             // Must also call markAaptRequested on the project to not just
@@ -735,6 +740,10 @@ public class PreCompilerBuilder extends BaseBuilder {
 
         // Also clean up lint
         EclipseLintClient.clearMarkers(project);
+
+        // clean the project repo
+        ProjectResources res = ResourceManager.getInstance().getProjectResources(project);
+        res.clear();
     }
 
     @Override
diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ProjectResources.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ProjectResources.java
index ccd16664a..68c225712 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ProjectResources.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ProjectResources.java
@@ -16,6 +16,7 @@
 
 package com.android.ide.eclipse.adt.internal.resources.manager;
 
+import com.android.SdkConstants;
 import com.android.annotations.NonNull;
 import com.android.ide.common.rendering.api.ResourceValue;
 import com.android.ide.common.resources.IntArrayWrapper;
@@ -26,6 +27,7 @@ import com.android.ide.common.resources.configuration.FolderConfiguration;
 import com.android.ide.eclipse.adt.internal.sdk.ProjectState;
 import com.android.ide.eclipse.adt.internal.sdk.Sdk;
 import com.android.ide.eclipse.adt.io.IFolderWrapper;
+import com.android.io.IAbstractFolder;
 import com.android.resources.ResourceType;
 import com.android.util.Pair;
 
@@ -48,6 +50,7 @@ import java.util.Map.Entry;
  *       on the fly.</li>
  *</ul>
  */
+@SuppressWarnings("deprecation")
 public class ProjectResources extends ResourceRepository {
     // project resources are defined as 0x7FXX#### where XX is the resource type (layout, drawable,
     // etc...). Using FF as the type allows for 255 resource types before we get a collision
@@ -65,12 +68,18 @@ public class ProjectResources extends ResourceRepository {
 
     private final IProject mProject;
 
+    public static ProjectResources create(IProject project) {
+        IFolder resFolder = project.getFolder(SdkConstants.FD_RESOURCES);
+
+        return new ProjectResources(project, new IFolderWrapper(resFolder));
+    }
+
     /**
      * Makes a ProjectResources for a given <var>project</var>.
      * @param project the project.
      */
-    public ProjectResources(IProject project) {
-        super(false /*isFrameworkRepository*/);
+    private ProjectResources(IProject project, IAbstractFolder resFolder) {
+        super(resFolder, false /*isFrameworkRepository*/);
         mProject = project;
     }
 
@@ -85,6 +94,7 @@ public class ProjectResources extends ResourceRepository {
     @NonNull
     public Map<ResourceType, Map<String, ResourceValue>> getConfiguredResources(
             @NonNull FolderConfiguration referenceConfig) {
+        ensureInitialized();
 
         Map<ResourceType, Map<String, ResourceValue>> resultMap =
             new EnumMap<ResourceType, Map<String, ResourceValue>>(ResourceType.class);
diff --git a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ResourceManager.java b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ResourceManager.java
index 1e12861d9..e407b6a78 100644
--- a/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ResourceManager.java
+++ b/eclipse/plugins/com.android.ide.eclipse.adt/src/com/android/ide/eclipse/adt/internal/resources/manager/ResourceManager.java
@@ -49,7 +49,6 @@ import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.QualifiedName;
 
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
@@ -151,14 +150,14 @@ public final class ResourceManager {
     /**
      * Returns the resources of a project.
      * @param project The project
-     * @return a ProjectResources object or null if none was found.
+     * @return a ProjectResources object
      */
     public ProjectResources getProjectResources(IProject project) {
         synchronized (mMap) {
             ProjectResources resources = mMap.get(project);
 
             if (resources == null) {
-                resources = new ProjectResources(project);
+                resources = ProjectResources.create(project);
                 mMap.put(project, resources);
             }
 
@@ -253,7 +252,7 @@ public final class ResourceManager {
 
                             // if it doesn't exist, we create it.
                             if (resources == null) {
-                                resources = new ProjectResources(project);
+                                resources = ProjectResources.create(project);
                                 mMap.put(project, resources);
                             }
                         }
@@ -491,16 +490,11 @@ public final class ResourceManager {
 
         FolderWrapper frameworkRes = new FolderWrapper(osResourcesPath);
         if (frameworkRes.exists()) {
-            FrameworkResources resources = new FrameworkResources();
-
-            try {
-                resources.loadResources(frameworkRes);
-                resources.loadPublicResources(frameworkRes, AdtPlugin.getDefault());
-                return resources;
-            } catch (IOException e) {
-                // since we test that folders are folders, and files are files, this shouldn't
-                // happen. We can ignore it.
-            }
+            FrameworkResources resources = new FrameworkResources(frameworkRes);
+
+            resources.loadResources();
+            resources.loadPublicResources(AdtPlugin.getDefault());
+            return resources;
         }
 
         return null;
@@ -512,62 +506,13 @@ public final class ResourceManager {
      */
     private void createProject(IProject project) {
         if (project.isOpen()) {
-            try {
-                if (project.hasNature(AdtConstants.NATURE_DEFAULT) == false) {
-                    return;
-                }
-            } catch (CoreException e1) {
-                // can't check the nature of the project? ignore it.
-                return;
-            }
-
-            IFolder resourceFolder = project.getFolder(SdkConstants.FD_RESOURCES);
-
-            ProjectResources projectResources;
             synchronized (mMap) {
-                projectResources = mMap.get(project);
+                ProjectResources projectResources = mMap.get(project);
                 if (projectResources == null) {
-                    projectResources = new ProjectResources(project);
+                    projectResources = ProjectResources.create(project);
                     mMap.put(project, projectResources);
                 }
             }
-            IdeScanningContext context = new IdeScanningContext(projectResources, project, true);
-
-            if (resourceFolder != null && resourceFolder.exists()) {
-                try {
-                    IResource[] resources = resourceFolder.members();
-
-                    for (IResource res : resources) {
-                        if (res.getType() == IResource.FOLDER) {
-                            IFolder folder = (IFolder)res;
-                            ResourceFolder resFolder = projectResources.processFolder(
-                                    new IFolderWrapper(folder));
-
-                            if (resFolder != null) {
-                                // now we process the content of the folder
-                                IResource[] files = folder.members();
-
-                                for (IResource fileRes : files) {
-                                    if (fileRes.getType() == IResource.FILE) {
-                                        IFile file = (IFile)fileRes;
-
-                                        context.startScanning(file);
-
-                                        resFolder.processFile(new IFileWrapper(file),
-                                                ResourceHelper.getResourceDeltaKind(
-                                                        IResourceDelta.ADDED), context);
-
-                                        context.finishScanning(file);
-                                    }
-                                }
-                            }
-                        }
-                    }
-                } catch (CoreException e) {
-                    // This happens if the project is closed or if the folder doesn't exist.
-                    // Since we already test for that, we can ignore this exception.
-                }
-            }
         }
     }
 
diff --git a/eclipse/plugins/com.android.ide.eclipse.tests/src/com/android/ide/eclipse/tests/functests/layoutRendering/ApiDemosRenderingTest.java b/eclipse/plugins/com.android.ide.eclipse.tests/src/com/android/ide/eclipse/tests/functests/layoutRendering/ApiDemosRenderingTest.java
index 5cb56473a..30f23de05 100644
--- a/eclipse/plugins/com.android.ide.eclipse.tests/src/com/android/ide/eclipse/tests/functests/layoutRendering/ApiDemosRenderingTest.java
+++ b/eclipse/plugins/com.android.ide.eclipse.tests/src/com/android/ide/eclipse/tests/functests/layoutRendering/ApiDemosRenderingTest.java
@@ -26,6 +26,7 @@ import com.android.ide.common.rendering.api.ResourceReference;
 import com.android.ide.common.rendering.api.ResourceValue;
 import com.android.ide.common.rendering.api.SessionParams;
 import com.android.ide.common.rendering.api.SessionParams.RenderingMode;
+import com.android.ide.common.resources.ResourceItem;
 import com.android.ide.common.resources.ResourceRepository;
 import com.android.ide.common.resources.ResourceResolver;
 import com.android.ide.common.resources.configuration.DensityQualifier;
@@ -43,7 +44,6 @@ import com.android.ide.common.resources.configuration.SmallestScreenWidthQualifi
 import com.android.ide.common.resources.configuration.TextInputMethodQualifier;
 import com.android.ide.common.resources.configuration.TouchScreenQualifier;
 import com.android.ide.common.sdk.LoadStatus;
-import com.android.ide.eclipse.adt.internal.resources.manager.ProjectResources;
 import com.android.ide.eclipse.adt.internal.resources.manager.ResourceManager;
 import com.android.ide.eclipse.adt.internal.sdk.AndroidTargetData;
 import com.android.ide.eclipse.tests.SdkTestCase;
@@ -215,8 +215,13 @@ public class ApiDemosRenderingTest extends SdkTestCase {
         ResourceRepository framework = ResourceManager.getInstance().loadFrameworkResources(target);
 
         // now load the project resources
-        ProjectResources project = new ProjectResources(null /*project*/);
-        project.loadResources(resFolder);
+        ResourceRepository project = new ResourceRepository(resFolder, false) {
+            @Override
+            protected ResourceItem createResourceItem(String name) {
+                return new ResourceItem(name);
+            }
+
+        };
 
         // Create a folder configuration that will be used for the rendering:
         FolderConfiguration config = getConfiguration();
diff --git a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/common/resources/platform/AttributeInfoTest.java b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/common/resources/platform/AttributeInfoTest.java
index 7ae96a8a2..cde12e597 100644
--- a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/common/resources/platform/AttributeInfoTest.java
+++ b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/common/resources/platform/AttributeInfoTest.java
@@ -18,11 +18,15 @@ package com.android.ide.common.resources.platform;
 import static com.android.SdkConstants.ANDROID_URI;
 import static com.android.SdkConstants.DOT_XML;
 
+import com.android.SdkConstants;
 import com.android.annotations.NonNull;
 import com.android.ide.common.api.IAttributeInfo.Format;
 import com.android.ide.common.resources.ResourceItem;
 import com.android.ide.common.resources.ResourceRepository;
 import com.android.ide.eclipse.adt.internal.editors.layout.gle2.DomUtilities;
+import com.android.ide.eclipse.mock.Mocks;
+import com.android.io.IAbstractFolder;
+import com.android.io.IAbstractResource;
 import com.android.resources.ResourceType;
 import com.android.utils.StdLogger;
 import com.google.common.base.Charsets;
@@ -219,11 +223,14 @@ public class AttributeInfoTest extends TestCase {
     }
 
     public void testResourcesExist() throws Exception {
+        IAbstractFolder folder = Mocks.createAbstractFolder(
+                SdkConstants.FD_RESOURCES, new IAbstractResource[0]);
+
         AttributeInfo info = new AttributeInfo("test", Format.REFERENCE_SET);
-        TestResourceRepository projectResources = new TestResourceRepository(false);
+        TestResourceRepository projectResources = new TestResourceRepository(folder,false);
         projectResources.addResource(ResourceType.STRING, "mystring");
         projectResources.addResource(ResourceType.DIMEN, "mydimen");
-        TestResourceRepository frameworkResources = new TestResourceRepository(true);
+        TestResourceRepository frameworkResources = new TestResourceRepository(folder, true);
         frameworkResources.addResource(ResourceType.LAYOUT, "mylayout");
 
         assertTrue(info.isValid("@string/mystring", null, null));
@@ -247,8 +254,8 @@ public class AttributeInfoTest extends TestCase {
     private class TestResourceRepository extends ResourceRepository {
         private Multimap<ResourceType, String> mResources = ArrayListMultimap.create();
 
-        protected TestResourceRepository(boolean isFrameworkRepository) {
-            super(isFrameworkRepository);
+        protected TestResourceRepository(IAbstractFolder resFolder, boolean isFrameworkRepository) {
+            super(resFolder, isFrameworkRepository);
         }
 
         void addResource(ResourceType type, String name) {
diff --git a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/resources/manager/ConfigMatchTest.java b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/resources/manager/ConfigMatchTest.java
index b45242b79..a6da135b6 100644
--- a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/resources/manager/ConfigMatchTest.java
+++ b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/resources/manager/ConfigMatchTest.java
@@ -16,8 +16,10 @@
 
 package com.android.ide.eclipse.adt.internal.editors.resources.manager;
 
+import com.android.SdkConstants;
 import com.android.ide.common.resources.ResourceFile;
 import com.android.ide.common.resources.ResourceFolder;
+import com.android.ide.common.resources.ResourceItem;
 import com.android.ide.common.resources.ResourceRepository;
 import com.android.ide.common.resources.SingleResourceFile;
 import com.android.ide.common.resources.configuration.FolderConfiguration;
@@ -25,6 +27,8 @@ import com.android.ide.eclipse.adt.internal.resources.manager.ProjectResources;
 import com.android.ide.eclipse.adt.io.IFileWrapper;
 import com.android.ide.eclipse.adt.io.IFolderWrapper;
 import com.android.ide.eclipse.mock.Mocks;
+import com.android.io.IAbstractFolder;
+import com.android.io.IAbstractResource;
 import com.android.resources.Keyboard;
 import com.android.resources.KeyboardState;
 import com.android.resources.Navigation;
@@ -46,7 +50,7 @@ public class ConfigMatchTest extends TestCase {
     private static final String MISC2_FILENAME = "bar.xml"; //$NON-NLS-1$
 
     private FolderConfiguration mDefaultConfig;
-    private ProjectResources mResources;
+    private ResourceRepository mResources;
     private FolderConfiguration config4;
     private FolderConfiguration config3;
     private FolderConfiguration config2;
@@ -60,8 +64,16 @@ public class ConfigMatchTest extends TestCase {
         mDefaultConfig = new FolderConfiguration();
         mDefaultConfig.createDefault();
 
+        IAbstractFolder folder = Mocks.createAbstractFolder(
+                SdkConstants.FD_RESOURCES, new IAbstractResource[0]);
+
         // create the project resources.
-        mResources = new ProjectResources(null /*project*/);
+        mResources = new ResourceRepository(folder, false) {
+            @Override
+            protected ResourceItem createResourceItem(String name) {
+                return new ResourceItem(name);
+            }
+        };
 
         // create 2 arrays of IResource. one with the filename being looked up, and one without.
         // Since the required API uses IResource, we can use MockFolder for them.
diff --git a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/mock/Mocks.java b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/mock/Mocks.java
index b57f3da29..65e2144be 100644
--- a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/mock/Mocks.java
+++ b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/mock/Mocks.java
@@ -25,6 +25,9 @@ import static org.easymock.EasyMock.expectLastCall;
 import static org.easymock.EasyMock.isA;
 import static org.easymock.EasyMock.replay;
 
+import com.android.io.IAbstractFolder;
+import com.android.io.IAbstractResource;
+
 import org.easymock.Capture;
 import org.easymock.EasyMock;
 import org.easymock.IAnswer;
@@ -145,6 +148,16 @@ public class Mocks {
         return file;
     }
 
+    public static IAbstractFolder createAbstractFolder(String name, IAbstractResource[] members) {
+        IAbstractFolder folder = createNiceMock(IAbstractFolder.class);
+        expect(folder.getName()).andReturn(name).anyTimes();
+        // expect(file.getLocation()).andReturn(new Path(name)).anyTimes();
+        expect(folder.listMembers()).andReturn(members).anyTimes();
+        replay(folder);
+
+        return folder;
+    }
+
     /**
      * Mock implementation of {@link IProject}.
      * <p/>
diff --git a/sdk_common/src/com/android/ide/common/resources/FrameworkResources.java b/sdk_common/src/com/android/ide/common/resources/FrameworkResources.java
index fbf592669..0e7e58a4f 100755
--- a/sdk_common/src/com/android/ide/common/resources/FrameworkResources.java
+++ b/sdk_common/src/com/android/ide/common/resources/FrameworkResources.java
@@ -59,8 +59,8 @@ public class FrameworkResources extends ResourceRepository {
     protected final Map<ResourceType, List<ResourceItem>> mPublicResourceMap =
         new EnumMap<ResourceType, List<ResourceItem>>(ResourceType.class);
 
-    public FrameworkResources() {
-        super(true /*isFrameworkRepository*/);
+    public FrameworkResources(@NonNull IAbstractFolder resFolder) {
+        super(resFolder, true /*isFrameworkRepository*/);
     }
 
     /**
@@ -102,8 +102,8 @@ public class FrameworkResources extends ResourceRepository {
      * @param resFolder The root folder of the resources
      * @param logger a logger to report issues to
      */
-    public void loadPublicResources(@NonNull IAbstractFolder resFolder, @Nullable ILogger logger) {
-        IAbstractFolder valueFolder = resFolder.getFolder(SdkConstants.FD_RES_VALUES);
+    public void loadPublicResources(@Nullable ILogger logger) {
+        IAbstractFolder valueFolder = getResFolder().getFolder(SdkConstants.FD_RES_VALUES);
         if (valueFolder.exists() == false) {
             return;
         }
diff --git a/sdk_common/src/com/android/ide/common/resources/ResourceRepository.java b/sdk_common/src/com/android/ide/common/resources/ResourceRepository.java
index 4f50f63ac..02c61d188 100755
--- a/sdk_common/src/com/android/ide/common/resources/ResourceRepository.java
+++ b/sdk_common/src/com/android/ide/common/resources/ResourceRepository.java
@@ -31,7 +31,6 @@ import com.android.resources.FolderTypeRelationship;
 import com.android.resources.ResourceFolderType;
 import com.android.resources.ResourceType;
 
-import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -59,32 +58,95 @@ import java.util.TreeSet;
  */
 public abstract class ResourceRepository {
 
-    protected final Map<ResourceFolderType, List<ResourceFolder>> mFolderMap =
+    private final IAbstractFolder mResourceFolder;
+
+    protected Map<ResourceFolderType, List<ResourceFolder>> mFolderMap =
         new EnumMap<ResourceFolderType, List<ResourceFolder>>(ResourceFolderType.class);
 
-    protected final Map<ResourceType, Map<String, ResourceItem>> mResourceMap =
+    protected Map<ResourceType, Map<String, ResourceItem>> mResourceMap =
             new EnumMap<ResourceType, Map<String, ResourceItem>>(
-            ResourceType.class);
+                    ResourceType.class);
 
-    private final Map<Map<String, ResourceItem>, Collection<ResourceItem>> mReadOnlyListMap =
+    private Map<Map<String, ResourceItem>, Collection<ResourceItem>> mReadOnlyListMap =
             new IdentityHashMap<Map<String, ResourceItem>, Collection<ResourceItem>>();
 
     private final boolean mFrameworkRepository;
+    private boolean mCleared = true;
+    private boolean mInitializing = false;
 
     protected final IntArrayWrapper mWrapper = new IntArrayWrapper(null);
 
     /**
      * Makes a resource repository
+     * @param resFolder the resource folder of the repository.
      * @param isFrameworkRepository whether the repository is for framework resources.
      */
-    protected ResourceRepository(boolean isFrameworkRepository) {
+    protected ResourceRepository(@NonNull IAbstractFolder resFolder,
+            boolean isFrameworkRepository) {
+        mResourceFolder = resFolder;
         mFrameworkRepository = isFrameworkRepository;
     }
 
+    public IAbstractFolder getResFolder() {
+        return mResourceFolder;
+    }
+
     public boolean isFrameworkRepository() {
         return mFrameworkRepository;
     }
 
+    public synchronized void clear() {
+        mCleared = true;
+        mFolderMap = new EnumMap<ResourceFolderType, List<ResourceFolder>>(
+                ResourceFolderType.class);
+        mResourceMap = new EnumMap<ResourceType, Map<String, ResourceItem>>(
+                ResourceType.class);
+
+        mReadOnlyListMap =
+            new IdentityHashMap<Map<String, ResourceItem>, Collection<ResourceItem>>();
+    }
+
+    /**
+     * Ensures that the repository has been initialized again after a call to
+     * {@link ResourceRepository#clear()}
+     *
+     * @return true if the repository was just re-initialized.
+     */
+    public synchronized boolean ensureInitialized() {
+        if (mCleared && !mInitializing) {
+            ScanningContext context = new ScanningContext(this);
+            mInitializing = true;
+
+            IAbstractResource[] resources = mResourceFolder.listMembers();
+
+            for (IAbstractResource res : resources) {
+                if (res instanceof IAbstractFolder) {
+                    IAbstractFolder folder = (IAbstractFolder)res;
+                    ResourceFolder resFolder = processFolder(folder);
+
+                    if (resFolder != null) {
+                        // now we process the content of the folder
+                        IAbstractResource[] files = folder.listMembers();
+
+                        for (IAbstractResource fileRes : files) {
+                            if (fileRes instanceof IAbstractFile) {
+                                IAbstractFile file = (IAbstractFile)fileRes;
+
+                                resFolder.processFile(file, ResourceDeltaKind.ADDED, context);
+                            }
+                        }
+                    }
+                }
+            }
+
+            mInitializing = false;
+            mCleared = false;
+            return true;
+        }
+
+        return false;
+    }
+
     /**
      * Adds a Folder Configuration to the project.
      * @param type The resource type.
@@ -140,6 +202,8 @@ public abstract class ResourceRepository {
             @NonNull ResourceFolderType type,
             @NonNull IAbstractFolder removedFolder,
             @Nullable ScanningContext context) {
+        ensureInitialized();
+
         // get the list of folders for the resource type.
         List<ResourceFolder> list = mFolderMap.get(type);
 
@@ -173,6 +237,8 @@ public abstract class ResourceRepository {
     public boolean hasResourceItem(@NonNull String url) {
         assert url.startsWith("@") || url.startsWith("?") : url;
 
+        ensureInitialized();
+
         int typeEnd = url.indexOf('/', 1);
         if (typeEnd != -1) {
             int nameBegin = typeEnd + 1;
@@ -204,6 +270,8 @@ public abstract class ResourceRepository {
      * @return true if the resource is known
      */
     public boolean hasResourceItem(@NonNull ResourceType type, @NonNull String name) {
+        ensureInitialized();
+
         Map<String, ResourceItem> map = mResourceMap.get(type);
 
         if (map != null) {
@@ -227,6 +295,8 @@ public abstract class ResourceRepository {
      */
     @NonNull
     protected ResourceItem getResourceItem(@NonNull ResourceType type, @NonNull String name) {
+        ensureInitialized();
+
         // looking for an existing ResourceItem with this type and name
         ResourceItem item = findDeclaredResourceItem(type, name);
 
@@ -308,6 +378,8 @@ public abstract class ResourceRepository {
      */
     @Nullable
     public ResourceFolder processFolder(@NonNull IAbstractFolder folder) {
+        ensureInitialized();
+
         // split the name of the folder in segments.
         String[] folderSegments = folder.getName().split(SdkConstants.RES_QUALIFIER_SEP);
 
@@ -332,11 +404,15 @@ public abstract class ResourceRepository {
      */
     @Nullable
     public List<ResourceFolder> getFolders(@NonNull ResourceFolderType type) {
+        ensureInitialized();
+
         return mFolderMap.get(type);
     }
 
     @NonNull
     public List<ResourceType> getAvailableResourceTypes() {
+        ensureInitialized();
+
         List<ResourceType> list = new ArrayList<ResourceType>();
 
         // For each key, we check if there's a single ResourceType match.
@@ -381,6 +457,8 @@ public abstract class ResourceRepository {
      */
     @NonNull
     public Collection<ResourceItem> getResourceItemsOfType(@NonNull ResourceType type) {
+        ensureInitialized();
+
         Map<String, ResourceItem> map = mResourceMap.get(type);
 
         if (map == null) {
@@ -402,6 +480,8 @@ public abstract class ResourceRepository {
      * @return true if the repository contains resources of the given type, false otherwise.
      */
     public boolean hasResourcesOfType(@NonNull ResourceType type) {
+        ensureInitialized();
+
         Map<String, ResourceItem> items = mResourceMap.get(type);
         return (items != null && items.size() > 0);
     }
@@ -413,15 +493,9 @@ public abstract class ResourceRepository {
      */
     @Nullable
     public ResourceFolder getResourceFolder(@NonNull IAbstractFolder folder) {
-        Collection<List<ResourceFolder>> values = mFolderMap.values();
+        ensureInitialized();
 
-        if (values.isEmpty()) { // This shouldn't be necessary, but has been observed
-            try {
-                loadResources(folder.getParentFolder());
-            } catch (IOException e) {
-                e.printStackTrace();
-            }
-        }
+        Collection<List<ResourceFolder>> values = mFolderMap.values();
 
         for (List<ResourceFolder> list : values) {
             for (ResourceFolder resFolder : list) {
@@ -445,6 +519,8 @@ public abstract class ResourceRepository {
     @Nullable
     public ResourceFile getMatchingFile(@NonNull String name, @NonNull ResourceFolderType type,
             @NonNull FolderConfiguration config) {
+        ensureInitialized();
+
         // get the folders for the given type
         List<ResourceFolder> folders = mFolderMap.get(type);
 
@@ -486,6 +562,7 @@ public abstract class ResourceRepository {
     @Nullable
     public List<ResourceFile> getSourceFiles(@NonNull ResourceType type, @NonNull String name,
             @Nullable FolderConfiguration referenceConfig) {
+        ensureInitialized();
 
         Collection<ResourceItem> items = getResourceItemsOfType(type);
 
@@ -517,6 +594,8 @@ public abstract class ResourceRepository {
     @NonNull
     public Map<ResourceType, Map<String, ResourceValue>> getConfiguredResources(
             @NonNull FolderConfiguration referenceConfig) {
+        ensureInitialized();
+
         return doGetConfiguredResources(referenceConfig);
     }
 
@@ -530,6 +609,7 @@ public abstract class ResourceRepository {
     @NonNull
     protected final Map<ResourceType, Map<String, ResourceValue>> doGetConfiguredResources(
             @NonNull FolderConfiguration referenceConfig) {
+        ensureInitialized();
 
         Map<ResourceType, Map<String, ResourceValue>> map =
             new EnumMap<ResourceType, Map<String, ResourceValue>>(ResourceType.class);
@@ -547,6 +627,8 @@ public abstract class ResourceRepository {
      */
     @NonNull
     public SortedSet<String> getLanguages() {
+        ensureInitialized();
+
         SortedSet<String> set = new TreeSet<String>();
 
         Collection<List<ResourceFolder>> folderList = mFolderMap.values();
@@ -569,6 +651,8 @@ public abstract class ResourceRepository {
      */
     @NonNull
     public SortedSet<String> getRegions(@NonNull String currentLanguage) {
+        ensureInitialized();
+
         SortedSet<String> set = new TreeSet<String>();
 
         Collection<List<ResourceFolder>> folderList = mFolderMap.values();
@@ -591,41 +675,17 @@ public abstract class ResourceRepository {
     }
 
     /**
-     * Loads the resources from a resource folder.
-     * <p/>
-     *
-     * @param rootFolder The folder to read the resources from. This is the top level
-     * resource folder (res/)
-     * @throws IOException
+     * Loads the resources.
      */
-    public void loadResources(@NonNull IAbstractFolder rootFolder)
-            throws IOException {
-        ScanningContext context = new ScanningContext(this);
-
-        IAbstractResource[] files = rootFolder.listMembers();
-        for (IAbstractResource file : files) {
-            if (file instanceof IAbstractFolder) {
-                IAbstractFolder folder = (IAbstractFolder) file;
-                ResourceFolder resFolder = processFolder(folder);
-
-                if (resFolder != null) {
-                    // now we process the content of the folder
-                    IAbstractResource[] children = folder.listMembers();
-
-                    for (IAbstractResource childRes : children) {
-                        if (childRes instanceof IAbstractFile) {
-                            resFolder.processFile((IAbstractFile) childRes,
-                                    ResourceDeltaKind.ADDED, context);
-                        }
-                    }
-                }
-            }
-        }
+    public void loadResources() {
+        clear();
+        ensureInitialized();
     }
 
-
     protected void removeFile(@NonNull Collection<ResourceType> types,
             @NonNull ResourceFile file) {
+        ensureInitialized();
+
         for (ResourceType type : types) {
             removeFile(type, file);
         }