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

jamis
The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...
New
mikecargal
Title: Hands-on Rust: question about get_component (page 295) (feel free to respond. “You dug you’re own hole… good luck”) I have somet...
New
AleksandrKudashkin
On the page xv there is an instruction to run bin/setup from the main folder. I downloaded the source code today (12/03/21) and can’t see...
New
Chrichton
Dear Sophie. I tried to do the “Authorization” exercise and have two questions: When trying to plug in an email-service, I found the ...
New
leba0495
Hello! Thanks for the great book. I was attempting the Trie (chap 17) exercises and for number 4 the solution provided for the autocorre...
New
jskubick
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
New
jskubick
I’m under the impression that when the reader gets to page 136 (“View Data with the Database Inspector”), the code SHOULD be able to buil...
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
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
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

Other popular topics Top

Devtalk
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
New
PragmaticBookshelf
Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...
New
AstonJ
I’ve been hearing quite a lot of comments relating to the sound of a keyboard, with one of the most desirable of these called ‘thock’, he...
New
DevotionGeo
The V Programming Language Simple language for building maintainable programs V is already mentioned couple of times in the forum, but I...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
AstonJ
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
New
AstonJ
If you want a quick and easy way to block any website on your Mac using Little Snitch simply… File &gt; New Rule: And select Deny, O...
New
DevotionGeo
I have always used antique keyboards like Cherry MX 1800 or Cherry MX 8100 and almost always have modified the switches in some way, like...
New
New
mindriot
Ok, well here are some thoughts and opinions on some of the ergonomic keyboards I have, I guess like mini review of each that I use enoug...
New

Sub Categories: