a.zampa

a.zampa

Kotlin and Android Development featuring Jetpack: error concerning function getCurrentStandings in BaseballDao.java

@mfazio23

I’m following the indications of the book and arriver ad chapter 10, but the app cannot be compiled due to an error in the BaseballDao.java class produced during the build process. I get the following errors:

  • Not sure how to convert a Cursor to this method’s return type (java.lang.Object).
  • Query method parameters should either be a type that can be converted into a database column or a List / Array that contains such type. You can consider adding a Type Adapter for this.
  • Unused parameter: continuation
  • Type of the parameter must be a class annotated with @Entity or a collection/array of it.
  • Not sure how to handle insert method’s return type.
  • Type of the parameter must be a class annotated with @Entity or a collection/array of it.
  • Not sure how to handle insert method’s return type.
  • Type of the parameter must be a class annotated with @Entity or a collection/array of it.
  • Not sure how to handle update method’s return type. Currently the supported return types are void, int or Int.
  • Type of the parameter must be a class annotated with @Entity or a collection/array of it.
  • Not sure how to handle update method’s return type. Currently the supported return types are void, int or Int.
  • The query returns some columns [teamId, division, wins, losses, winsLastTen, streakCount, streakType, divisionGamesBack, leagueGamesBack, id] which are not used by java.lang.Object. You can use @ColumnInfo annotation on the fields to specify the mapping. You can annotate the method with @RewriteQueriesToDropUnusedColumns to direct Room to rewrite your query to avoid fetching unused columns. You can suppress this warning by annotating the method with @SuppressWarnings(RoomWarnings.CURSOR_MISMATCH). Columns returned by the query: teamId, division, wins, losses, winsLastTen, streakCount, streakType, divisionGamesBack, leagueGamesBack, id.

The error message is

C:\Users\ale\AndroidStudioProjects\AndroidBaseballLeague\app\build\tmp\kapt3\stubs\debug\org\mathverse\androidbaseballleague\data\BaseballDao.java:31: error: Not sure how to convert a Cursor to this method’s return type (java.lang.Object).
public abstract java.lang.Object getCurrentStandings(@org.jetbrains.annotations.NotNull()

(I’m using org.mathverse.androidbaseballleague as package name, instead of dev.mfazio.abl).

The BaseballDao.java class contains the following lines

@org.jetbrains.annotations.Nullable()
@androidx.room.Query(value = "SELECT * FROM standings")
public abstract java.lang.Object getCurrentStandings(@org.jetbrains.annotations.NotNull()
kotlin.coroutines.Continuation<? super java.util.List<org.mathverse.androidbaseballleague.standings.TeamStanding>> continuation);

This is the only function of the database having prblems.
How can I solve this issue?
Thanks

Marked As Solved

a.zampa

a.zampa

Michael,

according to comment #11 to issue number 236612358, this problem is related to a change to Kotlin @Metadata annotation and can be solved forcing the dependency to the new version of kotlinx-metadata-jvm by adding

kapt “org.jetbrains.kotlinx:kotlinx-metadata-jvm:0.5.0”

This worked for me and solved another issue (room 2.4.2 didn’t allow to use vals into @Entity data classes asking, for the generated java class, setters for the corresponding variables).

Where Next?

Popular Pragmatic Bookshelf topics Top

raul
Hi Travis! Thank you for the cool book! :slight_smile: I made a list of issues and thought I could post them chapter by chapter. I’m rev...
New
curtosis
Running mix deps.get in the sensor_hub directory fails with the following error: ** (Mix) No SSH public keys found in ~/.ssh. An ssh aut...
New
jskubick
I’m running Android Studio “Arctic Fox” 2020.3.1 Patch 2, and I’m embarrassed to admit that I only made it to page 8 before running into ...
New
jgchristopher
“The ProductLive.Index template calls a helper function, live_component/3, that in turn calls on the modal component. ” Excerpt From: Br...
New
nicoatridge
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
s2k
Hi all, currently I wonder how the Tailwind colours work (or don’t work). For example, in app/views/layouts/application.html.erb I have...
New
dtonhofer
@parrt In the context of Chapter 4.3, the grammar Java.g4, meant to parse Java 6 compilation units, no longer passes ANTLR (currently 4....
New
redconfetti
Docker-Machine became part of the Docker Toolbox, which was deprecated in 2020, long after Docker Desktop supported Docker Engine nativel...
New
dachristenson
I just bought this book to learn about Android development, and I’m already running into a major issue in Ch. 1, p. 20: “Update activity...
New
roadbike
From page 13: On Python 3.7, you can install the libraries with pip by running these commands inside a Python venv using Visual Studio ...
New

Other popular topics Top

axelson
I’ve been really enjoying obsidian.md: It is very snappy (even though it is based on Electron). I love that it is all local by defaul...
New
New
Exadra37
I am asking for any distro that only has the bare-bones to be able to get a shell in the server and then just install the packages as we ...
New
Exadra37
Oh just spent so much time on this to discover now that RancherOS is in end of life but Rancher is refusing to mark the Github repo as su...
New
Margaret
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
1147 28379 760
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
PragmaticBookshelf
Rails 7 completely redefines what it means to produce fantastic user experiences and provides a way to achieve all the benefits of single...
New
New
New
Margaret
Ask Me Anything with Mark Volkmann @mvolkmann On February 24 and 25, we are giving you a chance to ask questions of PragProg author M...
New

Sub Categories: