[AI][logs] Crash: IllegalStateException – Query result empty, expected non-null Folder (FolderDao/FolderRepository)

[Ethran]

Error log (truncated for clarity)

java.lang.IllegalStateException: The query result was empty, but expected a single row to return a NON-NULL object of type <com.ethran.notable.data.db.Folder>.
    at com.ethran.notable.data.db.FolderDao_Impl.get$lambda$0(FolderDao_Impl.kt:221)
    at com.ethran.notable.data.db.FolderDao_Impl.get(FolderDao_Impl.kt:171)
    at com.ethran.notable.data.db.FolderRepository.get(Folder.kt:79)
    at com.ethran.notable.ui.components.BreadCrumbKt.getFolderList(BreadCrumb.kt:74)
    at com.ethran.notable.ui.components.BreadCrumbKt.BreadCrumb(BreadCrumb.kt:51)
    at com.ethran.notable.ui.views.HomeViewKt.Library(HomeView.kt:138)

Possible cause
A DAO/repository call expected a non-null Folder but the query returned no rows. The DAO signature returns a non-null Folder, so a missing row results in IllegalStateException. This may happen if a folder ID is stale/missing or was deleted.

Referenced code

• Folder entity, DAO and repository (DAO returns non-null; repository uses it):
  • Folder.kt (includes DAO and repository; repository get and DAO get):

    • notable/app/src/main/java/com/ethran/notable/data/db/Folder.kt

      Lines 1 to 87 in e6c2af5

      	package com.ethran.notable.data.db
      	import android.content.Context
      	import androidx.lifecycle.LiveData
      	import androidx.room.ColumnInfo
      	import androidx.room.Dao
      	import androidx.room.Entity
      	import androidx.room.ForeignKey
      	import androidx.room.Insert
      	import androidx.room.PrimaryKey
      	import androidx.room.Query
      	import androidx.room.Update
      	import java.util.Date
      	import java.util.UUID
      	@Entity(
      	foreignKeys = [ForeignKey(
      	entity = Folder::class,
      	parentColumns = arrayOf("id"),
      	childColumns = arrayOf("parentFolderId"),
      	onDelete = ForeignKey.CASCADE
      	)]
      	)
      	data class Folder(
      	@PrimaryKey
      	val id: String = UUID.randomUUID().toString(),
      	val title: String = "New Folder",
      	@ColumnInfo(index = true)
      	val parentFolderId: String? = null,
      	val createdAt: Date = Date(),
      	val updatedAt: Date = Date()
      	)
      	// DAO
      	@Dao
      	interface FolderDao {
      	@Query("SELECT * FROM folder WHERE parentFolderId IS :folderId")
      	fun getChildrenFolders(folderId: String?): LiveData<List<Folder>>
      	@Query("SELECT * FROM folder WHERE id IS :folderId")
      	fun get(folderId: String): Folder
      	@Insert
      	fun create(folder: Folder): Long
      	@Update
      	fun update(folder: Folder)
      	@Query("DELETE FROM folder WHERE id=:id")
      	fun delete(id: String)
      	}
      	class FolderRepository(context: Context) {
      	var db = AppDatabase.getDatabase(context).folderDao()
      	fun create(folder: Folder) {
      	db.create(folder)
      	}
      	fun update(folder: Folder) {
      	db.update(folder)
      	}
      	fun getAllInFolder(folderId: String? = null): LiveData<List<Folder>> {
      	return db.getChildrenFolders(folderId)
      	}
      	fun getParent(folderId: String? = null): String? {
      	if (folderId == null)
      	return null
      	val folder = db.get(folderId)
      	return folder.parentFolderId
      	}
      	fun get(folderId: String): Folder {
      	return db.get(folderId)
      	}
      	fun delete(id: String) {
      	db.delete(id)
      	}
      	}

    • Specific repository call site (FolderRepository.get):
      

      notable/app/src/main/java/com/ethran/notable/data/db/Folder.kt

      Line 79 in e6c2af5

      return db.get(folderId)

• BreadCrumb usage path:
  • getFolderList (calls FolderRepository.get and recurses):
    

    notable/app/src/main/java/com/ethran/notable/ui/components/BreadCrumb.kt

    Lines 72 to 83 in e6c2af5

    	fun getFolderList(context: Context, folderId: String): List<Folder> {
    	@Suppress("USELESS_ELVIS")
    	val folder = FolderRepository(context).get(folderId) ?: return emptyList()
    	val folderList = mutableListOf(folder)
    	val parentId = folder.parentFolderId
    	if (parentId != null) {
    	folderList.addAll(getFolderList(context, parentId))
    	}
    	return folderList
    	}

  • BreadCrumb composable:
    

    notable/app/src/main/java/com/ethran/notable/ui/components/BreadCrumb.kt

    Lines 1 to 71 in e6c2af5

    	package com.ethran.notable.ui.components
    	import android.content.Context
    	import androidx.compose.foundation.layout.Arrangement
    	import androidx.compose.foundation.layout.Row
    	import androidx.compose.foundation.layout.padding
    	import androidx.compose.material.Icon
    	import androidx.compose.material.Text
    	import androidx.compose.material.icons.Icons
    	import androidx.compose.material.icons.filled.ChevronRight
    	import androidx.compose.runtime.Composable
    	import androidx.compose.ui.Alignment
    	import androidx.compose.ui.Modifier
    	import androidx.compose.ui.platform.LocalContext
    	import androidx.compose.ui.text.style.TextDecoration
    	import androidx.compose.ui.text.style.TextOverflow
    	import androidx.compose.ui.unit.dp
    	import androidx.compose.ui.unit.sp
    	import com.ethran.notable.R
    	import com.ethran.notable.data.db.Folder
    	import com.ethran.notable.data.db.FolderRepository
    	import com.ethran.notable.ui.noRippleClickable
    	@Composable
    	fun BreadCrumb(
    	modifier: Modifier = Modifier,
    	folderId: String? = null,
    	fontSize: Int = 20,
    	onSelectFolderId: (String?) -> Unit
    	) {
    	val context = LocalContext.current
    	Row(
    	modifier = modifier.padding(horizontal = 8.dp, vertical = 4.dp),
    	verticalAlignment = Alignment.CenterVertically,
    	horizontalArrangement = Arrangement.spacedBy(4.dp)
    	) {
    	Text(
    	text = context.getString(R.string.home_view_name),
    	fontSize = fontSize.sp,
    	textDecoration = TextDecoration.Underline,
    	maxLines = 1,
    	overflow = TextOverflow.Ellipsis,
    	modifier = Modifier
    	.padding(end = 2.dp)
    	.noRippleClickable { onSelectFolderId(null) }
    	)
    	// ToolbarButton(iconId = R.drawable.home, onSelect = { onSelectFolderId(null) })
    	if (folderId != null) {
    	val folders: List<Folder> = getFolderList(context, folderId).reversed()
    	folders.forEach { f ->
    	Icon(
    	imageVector = Icons.Filled.ChevronRight,
    	contentDescription = null, // decorative
    	modifier = Modifier.padding(horizontal = 2.dp)
    	)
    	Text(
    	text = f.title,
    	fontSize = fontSize.sp,
    	textDecoration = TextDecoration.Underline,
    	maxLines = 1,
    	overflow = TextOverflow.Ellipsis,
    	modifier = Modifier.noRippleClickable { onSelectFolderId(f.id) }
    	)
    	}
    	}
    	}
    	}

• Home screen where BreadCrumb is used:
  • Library composable reference line:
    

    notable/app/src/main/java/com/ethran/notable/ui/views/HomeView.kt

    Line 138 in e6c2af5

    BreadCrumb(folderId = folderId) { navController.navigate("library" + if (it == null) "" else "?folderId=${it}") }