DATACMNS-90 - Allow Repository namespace handler to be configured to scan for inner class repositories.

We now optionally consider nested repository interfaces defined as inner-classes. This can be configured by setting the considerNestedRepositories property on EnableXXXRepository annotations or the consider-nested-repositories attribute to true - it defaults to false.

Original pull request: #50.

src/main/java/org/springframework/data/repository/config/AnnotationRepositoryConfigurationSource.java

@@ -48,6 +48,7 @@ public class AnnotationRepositoryConfigurationSource extends RepositoryConfigura
 	private static final String NAMED_QUERIES_LOCATION = "namedQueriesLocation";
 	private static final String QUERY_LOOKUP_STRATEGY = "queryLookupStrategy";
 	private static final String REPOSITORY_FACTORY_BEAN_CLASS = "repositoryFactoryBeanClass";
+	private static final String CONSIDER_NESTED_REPOSITORIES = "considerNestedRepositories";
 
 	private final AnnotationMetadata metadata;
 	private final AnnotationAttributes attributes;
@@ -222,4 +223,12 @@ public class AnnotationRepositoryConfigurationSource extends RepositoryConfigura
 		}
 		return typeFilters;
 	}
+
+	/* (non-Javadoc)
+	 * @see org.springframework.data.repository.config.RepositoryConfigurationSourceSupport#isConsideringNestedRepositoriesEnabled()
+	 */
+	@Override
+	public boolean isConsideringNestedRepositoriesEnabled() {
+		return attributes.getBoolean(CONSIDER_NESTED_REPOSITORIES);
+	}
 }

src/main/java/org/springframework/data/repository/config/RepositoryComponentProvider.java

@@ -1,3 +1,18 @@
+/*
+ * Copyright 2012-2013 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
 package org.springframework.data.repository.config;
 
 import java.io.IOException;
@@ -26,6 +41,8 @@ import org.springframework.util.Assert;
  */
 class RepositoryComponentProvider extends ClassPathScanningCandidateComponentProvider {
 
+	private boolean considerNestedRepositoryInterfaces;
+
 	/**
 	 * Creates a new {@link RepositoryComponentProvider} using the given {@link TypeFilter} to include components to be
 	 * picked up.
@@ -83,8 +100,26 @@ class RepositoryComponentProvider extends ClassPathScanningCandidateComponentPro
 
 		boolean isNonRepositoryInterface = !ClassUtils.isGenericRepositoryInterface(beanDefinition.getBeanClassName());
 		boolean isTopLevelType = !beanDefinition.getMetadata().hasEnclosingClass();
+		boolean isConsiderNestedRepositories = isConsiderNestedRepositoryInterfaces();
 
-		return isNonRepositoryInterface && isTopLevelType;
+		return isNonRepositoryInterface && (isTopLevelType || isConsiderNestedRepositories);
+	}
+
+	/**
+	 * @return the considerNestedRepositoryInterfaces
+	 */
+	public boolean isConsiderNestedRepositoryInterfaces() {
+		return considerNestedRepositoryInterfaces;
+	}
+
+	/**
+	 * Controls whether nested inner-class {@link Repository} interface definitions should be considered for automatic
+	 * discovery. This defaults to {@literal false}.
+	 * 
+	 * @param considerNestedRepositoryInterfaces
+	 */
+	public void setConsiderNestedRepositoryInterfaces(boolean considerNestedRepositoryInterfaces) {
+		this.considerNestedRepositoryInterfaces = considerNestedRepositoryInterfaces;
 	}
 
 	/**

src/main/java/org/springframework/data/repository/config/RepositoryConfigurationSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 the original author or authors.
+ * Copyright 2012-2013 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,6 +25,7 @@ import org.springframework.data.repository.query.QueryLookupStrategy;
  * Interface containing the configurable options for the Spring Data repository subsystem.
  * 
  * @author Oliver Gierke
+ * @author Thomas Darimont
  */
 public interface RepositoryConfigurationSource {
 
@@ -76,4 +77,9 @@ public interface RepositoryConfigurationSource {
 	 * @return
 	 */
 	Collection<String> getCandidates(ResourceLoader loader);
+
+	/**
+	 * @return true if the container should look for nested repository interface definitions.
+	 */
+	boolean isConsideringNestedRepositoriesEnabled();
 }

src/main/java/org/springframework/data/repository/config/RepositoryConfigurationSourceSupport.java

@@ -21,7 +21,6 @@ import java.util.HashSet;
 import java.util.Set;
 
 import org.springframework.beans.factory.config.BeanDefinition;
-import org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.StandardEnvironment;
 import org.springframework.core.io.ResourceLoader;
@@ -54,7 +53,8 @@ public abstract class RepositoryConfigurationSourceSupport implements Repository
 	 */
 	public Collection<String> getCandidates(ResourceLoader loader) {
 
-		ClassPathScanningCandidateComponentProvider scanner = new RepositoryComponentProvider(getIncludeFilters());
+		RepositoryComponentProvider scanner = new RepositoryComponentProvider(getIncludeFilters());
+		scanner.setConsiderNestedRepositoryInterfaces(isConsideringNestedRepositoriesEnabled());
 		scanner.setResourceLoader(loader);
 		scanner.setEnvironment(environment);
 
@@ -93,4 +93,10 @@ public abstract class RepositoryConfigurationSourceSupport implements Repository
 	protected Iterable<TypeFilter> getIncludeFilters() {
 		return Collections.emptySet();
 	}
+
+	/**
+	 * Controls whether nested repository-interfaces (e.g. defined as inner classes) should be considered by the
+	 * repository infrastructure.
+	 */
+	public abstract boolean isConsideringNestedRepositoriesEnabled();
 }

src/main/java/org/springframework/data/repository/config/XmlRepositoryConfigurationSource.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012 the original author or authors.
+ * Copyright 2012-2013 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -31,6 +31,7 @@ import org.w3c.dom.Element;
  * XML based {@link RepositoryConfigurationSource}. Uses configuration defined on {@link Element} attributes.
  * 
  * @author Oliver Gierke
+ * @author Thomas Darimont
  */
 public class XmlRepositoryConfigurationSource extends RepositoryConfigurationSourceSupport {
 
@@ -39,6 +40,7 @@ public class XmlRepositoryConfigurationSource extends RepositoryConfigurationSou
 	private static final String NAMED_QUERIES_LOCATION = "named-queries-location";
 	private static final String REPOSITORY_IMPL_POSTFIX = "repository-impl-postfix";
 	private static final String REPOSITORY_FACTORY_BEAN_CLASS_NAME = "factory-class";
+	private static final String CONSIDER_NESTED_REPOSITORIES = "consider-nested-repositories";
 
 	private final Element element;
 	private final ParserContext context;
@@ -148,4 +150,14 @@ public class XmlRepositoryConfigurationSource extends RepositoryConfigurationSou
 		String attribute = element.getAttribute(attributeName);
 		return StringUtils.hasText(attribute) ? attribute : null;
 	}
+
+	/* (non-Javadoc)
+	 * @see org.springframework.data.repository.config.RepositoryConfigurationSourceSupport#isConsideringNestedRepositoriesEnabled()
+	 */
+	@Override
+	public boolean isConsideringNestedRepositoriesEnabled() {
+
+		String attribute = getNullDefaultedAttribute(element, CONSIDER_NESTED_REPOSITORIES);
+		return attribute != null && Boolean.parseBoolean(attribute);
+	}
 }