DATACOUCH-141 - Change query lookup order and make N1QL default.

The @N1QL annotation was changed to @Query, for discoverability and also
convey that this is now the preferred method.

Order is now view if @View present, N1ql inline if @Query present with
a Statement, N1ql query derivation if @Query without attribute or no
annotation.

@View can be without attribute in order to compute the view
and design document from method name.

src/main/java/org/springframework/data/couchbase/core/view/Query.java

@@ -24,17 +24,32 @@ import java.lang.annotation.Target;
 
 import org.springframework.data.annotation.QueryAnnotation;
 import org.springframework.data.couchbase.core.CouchbaseTemplate;
+import org.springframework.data.couchbase.repository.query.StringN1qlBasedQuery;
 
 /**
  * Annotation to support the use of N1QL queries with Couchbase.
- *
+ * <p/>
  * Using it without parameter will resolve the query from the method name. Providing a value
  * (an inline N1QL statement) will execute that statement instead.
- *
+ * <p/>
  * In this case, one can use a placeholder notation of {@code ?0}, {@code ?1} and so on.
- *
- * Also, the placeholder {@code $BUCKET$} can be used to be replaced by the underlying {@link CouchbaseTemplate}
- * associated bucket name.
+ * <p/>
+ * Also, the following placeholders can be used to be replaced by the underlying {@link CouchbaseTemplate}
+ * associated information:
+ * <ul>
+ *  <li>
+ *    {@value StringN1qlBasedQuery#PLACEHOLDER_SELECT_FROM}
+ *    (see {@link StringN1qlBasedQuery#PLACEHOLDER_SELECT_FROM})
+ *  </li>
+ *  <li>
+ *    {@value StringN1qlBasedQuery#PLACEHOLDER_BUCKET}
+ *    (see {@link StringN1qlBasedQuery#PLACEHOLDER_BUCKET})
+ *  </li>
+ *  <li>
+ *    {@value StringN1qlBasedQuery#PLACEHOLDER_ENTITY}
+ *    (see {@link StringN1qlBasedQuery#PLACEHOLDER_ENTITY})
+ *  </li>
+ * </ul>
  *
  * @author Simon Baslé.
  */
@@ -42,12 +57,12 @@ import org.springframework.data.couchbase.core.CouchbaseTemplate;
 @Target(ElementType.METHOD)
 @Retention(RetentionPolicy.RUNTIME)
 @QueryAnnotation
-public @interface N1QL {
+public @interface Query {
 
-    /**
-     * Takes a N1QL statement string to define the actual query to be executed. This one will take precedence over the
-     * method name then.
-     */
-    String value() default "";
+  /**
+   * Takes a N1QL statement string to define the actual query to be executed. This one will take precedence over the
+   * method name then.
+   */
+  String value() default "";
 
 }

src/main/java/org/springframework/data/couchbase/core/view/View.java

@@ -35,19 +35,19 @@ public @interface View {
   /**
    * The name of the Design Document to use.
    * <p/>
-   * This field is mandatory.
+   * If the {@link #viewName()} field is set, this field is mandatory.
    *
    * @return name of the Design Document.
    */
-  String designDocument();
+  String designDocument() default "";
 
   /**
    * The name of the View to use.
    * <p/>
-   * This field is mandatory.
+   * If the {@link #designDocument()} field is set, his field is mandatory.
    *
    * @return name of the View
    */
-  String viewName();
+  String viewName() default "";
 
 }

src/main/java/org/springframework/data/couchbase/repository/query/CouchbaseQueryMethod.java

@@ -21,7 +21,7 @@ import java.lang.reflect.Method;
 import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.data.couchbase.core.mapping.CouchbasePersistentEntity;
 import org.springframework.data.couchbase.core.mapping.CouchbasePersistentProperty;
-import org.springframework.data.couchbase.core.view.N1QL;
+import org.springframework.data.couchbase.core.view.Query;
 import org.springframework.data.couchbase.core.view.View;
 import org.springframework.data.mapping.context.MappingContext;
 import org.springframework.data.repository.core.RepositoryMetadata;
@@ -57,6 +57,19 @@ public class CouchbaseQueryMethod extends QueryMethod {
     return getViewAnnotation() != null;
   }
 
+  /**
+   * If the method has a @View annotation with the designDocument and viewName specified.
+   *
+   * @return true if it has the annotation and full view specified.
+   */
+  public boolean hasViewSpecification() {
+    View annotation = getViewAnnotation();
+    if (annotation == null) {
+      return false;
+    }
+    return StringUtils.hasText(annotation.designDocument()) && StringUtils.hasText(annotation.viewName());
+  }
+
   /**
    * Returns the @View annotation if set, null otherwise.
    *
@@ -67,7 +80,7 @@ public class CouchbaseQueryMethod extends QueryMethod {
   }
 
   /**
-   * If the method has a @N1QL annotation.
+   * If the method has a @Query annotation.
    *
    * @return true if it has the annotation, false otherwise.
    */
@@ -76,16 +89,16 @@ public class CouchbaseQueryMethod extends QueryMethod {
   }
 
   /**
-   * Returns the @N1QL annotation if set, null otherwise.
+   * Returns the @Query annotation if set, null otherwise.
    *
    * @return the n1ql annotation if present.
    */
-  public N1QL getN1qlAnnotation() {
-    return method.getAnnotation(N1QL.class);
+  public Query getN1qlAnnotation() {
+    return method.getAnnotation(Query.class);
   }
 
   /**
-   * If the method has a @N1QL annotation with an inline N1QL statement inside.
+   * If the method has a @Query annotation with an inline Query statement inside.
    *
    * @return true if this has the annotation and N1QL inline statement, false otherwise.
    */
@@ -94,7 +107,7 @@ public class CouchbaseQueryMethod extends QueryMethod {
   }
 
   /**
-   * Returns the query string declared in a {@link N1QL} annotation or {@literal null} if neither the annotation found
+   * Returns the query string declared in a {@link Query} annotation or {@literal null} if neither the annotation found
    * nor the attribute was specified.
    *
    * @return the query statement if present.

src/main/java/org/springframework/data/couchbase/repository/query/N1qlQueryCreator.java

@@ -218,7 +218,7 @@ public class N1qlQueryCreator extends AbstractQueryCreator<LimitPath, Expression
       case WITHIN:
       case NEAR:
       default:
-        throw new IllegalArgumentException("Unsupported keyword");
+        throw new IllegalArgumentException("Unsupported keyword in N1QL query derivation");
     }
   }
 

src/main/java/org/springframework/data/couchbase/repository/query/StringN1qlBasedQuery.java

@@ -34,8 +34,22 @@ import org.springframework.data.repository.query.RepositoryQuery;
  */
 public class StringN1qlBasedQuery extends AbstractN1qlBasedQuery {
 
+  /**
+   * Use this placeholder in a {@link org.springframework.data.couchbase.core.view.Query @Query} annotation's inline
+   * statement. This will be replaced by the correct <code>SELECT x FROM y</code> clause needed for entity mapping.
+   */
   public static final String PLACEHOLDER_SELECT_FROM = "$SELECT_ENTITY$";
+
+  /**
+   * Use this placeholder in a {@link org.springframework.data.couchbase.core.view.Query @Query} annotation's inline
+   * statement. This will be replaced by the bucket name corresponding to the repository's entity.
+   */
   public static final String PLACEHOLDER_BUCKET = "$BUCKET$";
+
+  /**
+   * Use this placeholder in a {@link org.springframework.data.couchbase.core.view.Query @Query} annotation's inline
+   * statement. This will be replaced by the fields allowing to construct the repository's entity (SELECT clause).
+   */
   public static final String PLACEHOLDER_ENTITY = "$ENTITY$";
 
   private final Statement statement;

src/main/java/org/springframework/data/couchbase/repository/query/ViewBasedCouchbaseQuery.java

@@ -69,11 +69,13 @@ public class ViewBasedCouchbaseQuery implements RepositoryQuery {
    * @return the design document name.
    */
   private String designDocName() {
-    if (method.hasViewAnnotation()) {
-      return method.getViewAnnotation().designDocument();
-    } else {
-      return StringUtils.uncapitalize(method.getEntityInformation().getJavaType().getSimpleName());
-    }
+      if (method.hasViewSpecification()) {
+        return method.getViewAnnotation().designDocument();
+      } else if (method.hasViewAnnotation()) {
+        return StringUtils.uncapitalize(method.getEntityInformation().getJavaType().getSimpleName());
+      } else {
+        throw new IllegalStateException("View-based query should only happen on a method with @View annotation");
+      }
   }
 
   /**
@@ -82,10 +84,12 @@ public class ViewBasedCouchbaseQuery implements RepositoryQuery {
    * @return the view name.
    */
   private String viewName() {
-    if (method.hasViewAnnotation()) {
+    if (method.hasViewSpecification()) {
       return method.getViewAnnotation().viewName();
-    } else {
+    } else if (method.hasViewAnnotation()) {
       return StringUtils.uncapitalize(method.getName().replaceFirst("find", ""));
+    } else {
+      throw new IllegalStateException("View-based query should only happen on a method with @View annotation");
     }
   }
 

src/main/java/org/springframework/data/couchbase/repository/support/CouchbaseRepositoryFactory.java

@@ -136,17 +136,17 @@ public class CouchbaseRepositoryFactory extends RepositoryFactorySupport {
       CouchbaseQueryMethod queryMethod = new CouchbaseQueryMethod(method, metadata, mappingContext);
       String namedQueryName = queryMethod.getNamedQueryName();
 
-      if (queryMethod.hasN1qlAnnotation()) {
+      if (queryMethod.hasViewAnnotation()) {
+        return new ViewBasedCouchbaseQuery(queryMethod, couchbaseOperations);
+      } else if (queryMethod.hasN1qlAnnotation()) {
         if (queryMethod.hasInlineN1qlQuery()) {
           return new StringN1qlBasedQuery(queryMethod.getInlineN1qlQuery(), queryMethod, couchbaseOperations);
         } else if (namedQueries.hasQuery(namedQueryName)) {
           String namedQuery = namedQueries.getQuery(namedQueryName);
           return new StringN1qlBasedQuery(namedQuery, queryMethod, couchbaseOperations);
-        } else {
-          return new PartTreeN1qlBasedQuery(queryMethod, couchbaseOperations);
-        }
+        } //otherwise will do default, queryDerivation
       }
-      return new ViewBasedCouchbaseQuery(queryMethod, couchbaseOperations);
+      return new PartTreeN1qlBasedQuery(queryMethod, couchbaseOperations);
     }
   }