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

belgoros
Following the steps described in Chapter 6 of the book, I’m stuck with running the migration as described on page 84: bundle exec sequel...
New
lirux
Hi Jamis, I think there’s an issue with a test on chapter 6. I own the ebook, version P1.0 Feb. 2019. This test doesn’t pass for me: ...
New
herminiotorres
Hi @Margaret , On page VII the book tells us the example and snippets will be all using Elixir version 1.11 But on page 3 almost the en...
New
hgkjshegfskef
The test is as follows: Scenario: Intersecting a scaled sphere with a ray Given r ← ray(point(0, 0, -5), vector(0, 0, 1)) And s ← sphere...
New
dsmith42
Hey there, I’m enjoying this book and have learned a few things alredayd. However, in Chapter 4 I believe we are meant to see the “&gt;...
New
taguniversalmachine
It seems the second code snippet is missing the code to set the current_user: current_user: Accounts.get_user_by_session_token(session["...
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
Henrai
Hi, I’m working on the Chapter 8 of the book. After I add add the point_offset, I’m still able to see acne: In the image above, I re...
New
EdBorn
Title: Agile Web Development with Rails 7: (page 70) I am running windows 11 pro with rails 7.0.3 and ruby 3.1.2p20 (2022-04-12 revision...
New
ggerico
I got this error when executing the plot files on macOS Ventura 13.0.1 with Python 3.10.8 and matplotlib 3.6.1: programming_ML/code/03_...
New

Other popular topics Top

AstonJ
What chair do you have while working… and why? Is there a ‘best’ type of chair or working position for developers?
New
ohm
Which, if any, games do you play? On what platform? I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
DevotionGeo
I know that these benchmarks might not be the exact picture of real-world scenario, but still I expect a Rust web framework performing a ...
New
AstonJ
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...
New
Rainer
My first contact with Erlang was about 2 years ago when I used RabbitMQ, which is written in Erlang, for my job. This made me curious and...
New
AstonJ
Just done a fresh install of macOS Big Sur and on installing Erlang I am getting: asdf install erlang 23.1.2 Configure failed. checking ...
New
AstonJ
This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...
New
PragmaticBookshelf
Programming Ruby is the most complete book on Ruby, covering both the language itself and the standard library as well as commonly used t...
New
New
PragmaticBookshelf
A concise guide to MySQL 9 database administration, covering fundamental concepts, techniques, and best practices. Neil Smyth MySQL...
New

Sub Categories: