DATAMONGO-1811 - Update documentation of MongoOperations.executeCommand.

Update Javadoc and reference documentation.

Author: christophstrobl

spring-data-mongodb/src/main/java/org/springframework/data/mongodb/core/MongoOperations.java

@@ -72,11 +72,11 @@ public interface MongoOperations extends FluentMongoOperations {
 	String getCollectionName(Class<?> entityClass);
 
 	/**
-	 * Execute the a MongoDB command expressed as a JSON string. This will call the method JSON.parse that is part of the
-	 * MongoDB driver to convert the JSON string to a Document. Any errors that result from executing this command will be
+	 * Execute the a MongoDB command expressed as a JSON string. Parsing is delegated to {@link Document#parse(String)} to
+	 * obtain the {@link Document} holding the actual command. Any errors that result from executing this command will be
 	 * converted into Spring's DAO exception hierarchy.
 	 *
-	 * @param jsonCommand a MongoDB command expressed as a JSON string.
+	 * @param jsonCommand a MongoDB command expressed as a JSON string. Must not be {@literal null}.
 	 * @return a result object returned by the action.
 	 */
 	Document executeCommand(String jsonCommand);
@@ -851,8 +851,8 @@ <T> T findAndModify(Query query, Update update, FindAndModifyOptions options, Cl
 	 * If you object has an "Id' property, it will be set with the generated Id from MongoDB. If your Id property is a
 	 * String then MongoDB ObjectId will be used to populate that string. Otherwise, the conversion from ObjectId to your
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See
-	 * <a href="http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" >
-	 * Spring's Type Conversion"</a> for more details.
+	 * <a href="http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's Type
+	 * Conversion"</a> for more details.
 	 * <p/>
 	 * <p/>
 	 * Insert is used to initially store the object into the database. To update an existing object use the save method.
@@ -908,8 +908,8 @@ <T> T findAndModify(Query query, Update update, FindAndModifyOptions options, Cl
 	 * If you object has an "Id' property, it will be set with the generated Id from MongoDB. If your Id property is a
 	 * String then MongoDB ObjectId will be used to populate that string. Otherwise, the conversion from ObjectId to your
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See
-	 * <a href="http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" >
-	 * Spring's Type Conversion"</a> for more details.
+	 * <a href="http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation" > Spring's Type
+	 * Conversion"</a> for more details.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 */
@@ -925,8 +925,8 @@ <T> T findAndModify(Query query, Update update, FindAndModifyOptions options, Cl
 	 * If you object has an "Id' property, it will be set with the generated Id from MongoDB. If your Id property is a
 	 * String then MongoDB ObjectId will be used to populate that string. Otherwise, the conversion from ObjectId to your
 	 * property type will be handled by Spring's BeanWrapper class that leverages Type Conversion API. See <a
-	 * http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation">Spring's
-	 * Type Conversion"</a> for more details.
+	 * http://docs.spring.io/spring/docs/current/spring-framework-reference/core.html#validation">Spring's Type
+	 * Conversion"</a> for more details.
 	 *
 	 * @param objectToSave the object to store in the collection. Must not be {@literal null}.
 	 * @param collectionName name of the collection to store the object in. Must not be {@literal null}.

src/main/asciidoc/reference/mongodb.adoc

@@ -2419,13 +2419,14 @@ NOTE: Collection creation allows customization via `CollectionOptions` and suppo
 [[mongo-template.commands]]
 == Executing Commands
 
-You can also get at the MongoDB driver's `DB.command( )` method using the `executeCommand(…)` methods on `MongoTemplate`. These will also perform exception translation into Spring's `DataAccessException` hierarchy.
+You can also get at the MongoDB driver's `MongoDatabase.runCommand( )` method using the `executeCommand(…)` methods on `MongoTemplate`. These will also perform exception translation into Spring's `DataAccessException` hierarchy.
 
 [[mongo-template.commands.execution]]
 === Methods for executing commands
 
-* `CommandResult` *executeCommand* `(Document command)` Execute a MongoDB command.
-* `CommandResult` *executeCommand* `(String jsonCommand)` Execute the a MongoDB command expressed as a JSON string.
+* `Document` *executeCommand* `(Document command)` Execute a MongoDB command.
+* `Document` *executeCommand* `(Document command, ReadPreference readPreference)` Execute a MongoDB command using the given nullable MongoDB `ReadPreference`.
+* `Document` *executeCommand* `(String jsonCommand)` Execute the a MongoDB command expressed as a JSON string.
 
 [[mongodb.mapping-usage.events]]
 == Lifecycle Events