driver-legacy/src/main/com/mongodb/DB.java
public CommandResult command(final String command) {
        return command(new BasicDBObject(command, Boolean.TRUE), getReadPreference());
    }
public CommandResult command(final String command) {
        return command(new BasicDBObject(command, Boolean.TRUE), getReadPreference());
    }
Executes a database command. This method constructs a simple DBObject using {@code command} as the field name and {@code true} as its
value, and calls {@link DB#command(DBObject, ReadPreference) } with the default read preference for the database.

@param command command to execute
@return result of command from the database
@throws MongoException if the command failed
@mongodb.driver.manual tutorial/use-database-commands Commands