DATAKV-268 - Polishing.

Add test for non annotation driven keyspace resolution and update documentation.

Original Pull Request: #46

Author: christophstrobl

src/main/asciidoc/key-value-repositories.adoc

@@ -89,6 +89,10 @@ template.findAllOf(User.class);   <2>
 <2> Returns only elements of type `User` stored in `persons` keyspace.
 ====
 
+TIP: `@KeySpace` supports https://docs.spring.io/spring/docs/{springVersion}/spring-framework-reference/core.html#expressions[SpEL] expressions allowing dynamic keyspace configuration.
+
+5.2.0.M3
+
 [[key-value.keyspaces-custom]]
 === Custom KeySpace Annotation
 

src/main/java/org/springframework/data/keyvalue/core/mapping/BasicKeyValuePersistentEntity.java

@@ -55,9 +55,11 @@ public BasicKeyValuePersistentEntity(TypeInformation<T> information,
 		String keySpace = AnnotationBasedKeySpaceResolver.INSTANCE.resolveKeySpace(type);
 
 		if (StringUtils.hasText(keySpace)) {
+
 			this.keyspace = keySpace;
 			this.keyspaceExpression = detectExpression(keySpace);
 		} else {
+
 			this.keyspace = resolveKeyspace(fallbackKeySpaceResolver, type);
 			this.keyspaceExpression = null;
 		}
@@ -67,8 +69,8 @@ public BasicKeyValuePersistentEntity(TypeInformation<T> information,
 	 * Returns a SpEL {@link Expression} if the given {@link String} is actually an expression that does not evaluate to a
 	 * {@link LiteralExpression} (indicating that no subsequent evaluation is necessary).
 	 *
-	 * @param potentialExpression can be {@literal null}
-	 * @return
+	 * @param potentialExpression must not be {@literal null}
+	 * @return the parsed {@link Expression} or {@literal null}.
 	 */
 	@Nullable
 	private static Expression detectExpression(String potentialExpression) {

src/test/java/org/springframework/data/keyvalue/core/mapping/BasicKeyValuePersistentEntityUnitTests.java

@@ -22,7 +22,6 @@
 import java.util.Map;
 
 import org.junit.Test;
-
 import org.springframework.data.keyvalue.annotation.KeySpace;
 import org.springframework.data.keyvalue.core.mapping.context.KeyValueMappingContext;
 import org.springframework.data.mapping.context.MappingContext;
@@ -41,28 +40,38 @@ public class BasicKeyValuePersistentEntityUnitTests {
 	@Test // DATAKV-268
 	public void shouldDeriveKeyspaceFromClassName() {
 
-		KeyValuePersistentEntity<?, ?> persistentEntity = mappingContext.getPersistentEntity(KeyspaceEntity.class);
-
-		assertThat(persistentEntity.getKeySpace()).isEqualTo(KeyspaceEntity.class.getName());
+		assertThat(mappingContext.getPersistentEntity(KeyspaceEntity.class).getKeySpace())
+				.isEqualTo(KeyspaceEntity.class.getName());
 	}
 
 	@Test // DATAKV-268
 	public void shouldEvaluateKeyspaceExpression() {
 
 		KeyValuePersistentEntity<?, ?> persistentEntity = mappingContext.getPersistentEntity(ExpressionEntity.class);
-
 		persistentEntity.setEvaluationContextProvider(
 				new ExtensionAwareEvaluationContextProvider(Collections.singletonList(new SampleExtension())));
 
 		assertThat(persistentEntity.getKeySpace()).isEqualTo("some");
 	}
 
+	@Test // DATAKV-268
+	public void shouldEvaluateEntityWithoutKeyspace() {
+
+		KeyValuePersistentEntity<?, ?> persistentEntity = mappingContext.getPersistentEntity(NoKeyspaceEntity.class);
+		persistentEntity.setEvaluationContextProvider(
+				new ExtensionAwareEvaluationContextProvider(Collections.singletonList(new SampleExtension())));
+
+		assertThat(persistentEntity.getKeySpace()).isEqualTo(NoKeyspaceEntity.class.getName());
+	}
+
 	@KeySpace("#{myProperty}")
 	static class ExpressionEntity {}
 
 	@KeySpace
 	static class KeyspaceEntity {}
 
+	static class NoKeyspaceEntity {}
+
 	static class SampleExtension implements EvaluationContextExtension {
 
 		@Override