Java 存储库MVVM体系结构中的堆栈溢出错误

我想在我的应用程序中使用Room db实现MVVM。我跟踪了这个链接

我在创建视图模型实例时出错。当我解决这个问题时，我遇到了如下新错误：

     Process: com.example.dailyfaithapp, PID: 7341
    java.lang.StackOverflowError: stack size 8192KB
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
2020-04-28 18:10:23.865 7341-7341/com.example.dailyfaithapp E/AndroidRuntime:     at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
2020-04-28 18:10:29.491 7341-7356/com.example.dailyfaithapp I/e.dailyfaithap: Background concurrent copying GC freed 395507(38MB) AllocSpace objects, 1(3804KB) LOS objects, 5% free, 95MB/101MB, paused 337us total 142.457ms
2020-04-28 18:10:29.720 7341-7341/com.example.dailyfaithapp I/chatty: uid=10141(com.example.dailyfaithapp) identical 8100 lines
2020-04-28 18:10:29.720 7341-7341/com.example.dailyfaithapp E/AndroidRuntime:     at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
2020-04-28 18:10:29.720 7341-7341/com.example.dailyfaithapp E/AndroidRuntime:     at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.Repositories.FavouriteRepository.getAllFavourites(FavouriteRepository.java:25)
        at com.example.dailyfaithapp.ViewModels.FavouritesViewModel.<init>(FavouritesViewModel.java:26)
        at com.example.dailyfaithapp.FavouritesViewModelFactory.create(FavouritesViewModelFactory.java:25)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:187)
        at androidx.lifecycle.ViewModelProvider.get(ViewModelProvider.java:150)
        at com.example.dailyfaithapp.Activities.FavouritesActivity.setUpUI(FavouritesActivity.java:72)
        at com.example.dailyfaithapp.Activities.FavouritesActivity.onCreate(FavouritesActivity.java:54)
        at android.app.Activity.performCreate(Activity.java:7802)
        at android.app.Activity.performCreate(Activity.java:7791)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1299)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
        at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
        at android.os.Handler.dispatchMessage(Handler.java:107)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7356)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)

这是我的视图模型

public class FavouritesViewModel extends AndroidViewModel {

        public FavouriteRepository mRepository;

        public LiveData<List<Favourites>> mAllFavourites;
        private MutableLiveData<List<Favourites>> favouriteSearchResults;

        public FavouritesViewModel (Application application) {
                super(application);
                mRepository = new FavouriteRepository(application);
                mAllFavourites = mRepository.getAllFavourites();
                favouriteSearchResults = mRepository.getFavouritesSearch();
        }
        public LiveData<List<Favourites>> getmAllFavourites() { return mAllFavourites; }

}

刀

@Dao
公共接口收藏夹DAO{
@查询（“从收藏夹中选择*）
LiveData GetAllFavorites（）；
@查询（“从收藏夹中选择*）
列出loadAllFavorites（）；
@插入（onConflict=OnConflictStrategy.REPLACE）
void insertallfavorites（收藏夹…收藏夹）；
@插入（onConflict=OnConflictStrategy.REPLACE）
公共空白插入收藏夹（收藏夹收藏夹）；
@删除
作废删除（收藏夹收藏夹）；
}

在调试时，我看到repository方法的getAllFavorites（）被称为continuous，因为内存已经满了

这是我的活动

    public void setUpUI(){

        recyclerView = findViewById(R.id.recycler_view_favourites);
        constraintLayoutEmpty = findViewById(R.id.constraint_empty);
        imageViewBack = findViewById(R.id.imageView_back);

        imageViewBack.setOnClickListener(this);



        favouritesViewModel = new ViewModelProvider(this,
                new FavouritesViewModelFactory(getApplication())).get(FavouritesViewModel.class);


        favouritesViewModel.getmAllFavourites().observe(this,
                new Observer<List<Favourites>>() {
            @Override
            public void onChanged(@Nullable final List<Favourites> products) {

                favouritesArrayList = products;
            }
        });
}

public void setUpUI（）{
recyclerView=findViewById（R.id.recycler\u view\u Favorites）；
constraintLayoutEmpty=findViewById（R.id.constraint\u empty）；
imageViewBack=findViewById（R.id.imageView\u back）；
setOnClickListener（这个）；
FavoritesViewModel=新的ViewModelProvider（此，
新建FavoriteSviewmodelFactory（getApplication（））.get（FavoriteSviewmodel.class）；
FavoritesViewModel.GetMallFavorites（）。观察（此，
新观察员（）{
@凌驾
更改后的公共void（@Nullable final List products）{
FavoriteSarraylist=产品；
}
});
}

在创建活动时调用setUpUI

---

请帮忙。谢谢。

在

收藏库中

您正在做：

public LiveData<List<Favourites>> getAllFavourites() {
    return getAllFavourites();
}

public LiveData getAllFavorites（）{
返回getAllFavorites（）；
}

此方法正在调用自身。 你得看看你需要什么，而不是自己打电话

我想你在下一种方法中也有同样的问题：

public MutableLiveData<List<Favourites>> getFavouritesSearch() {
    return getFavouritesSearch();
}

public MutableLiveData getFavoriteSearch（）{
返回getFavoriteSearch（）；
}

---

你需要解决这些问题。

我不明白。。？该方法正在被调用，我不知道如何调用。@Sid它是从

FavoriteSviewmodel

类构造函数调用的，我相信它是从

FavoriteSviewmodelFactory

类的

create

方法调用的，在创建viewmodel:-|没有理解您。意思是它会被调用两次吗？@Sid我无法帮你编写代码，因为我不知道你想做什么。我可以告诉你哪里做错了什么。您必须调用

favoritesdao

中的方法，从数据库中获取数据，而不是执行递归调用。是一个很好的开始如何使用房间数据库的地方。您还可以了解livedata和viewmodel@Sid

getAllFavorites

被无限期调用

，直到堆栈溢出，这就是获得异常的原因。只需在

getAllFavorites

中放一个日志，自己查看即可。

@Database(entities = {Favourites.class}, version = 1, exportSchema = false)
public  abstract class FavouritesDatabase extends RoomDatabase {

        public abstract FavouritesDAO favouritesDAO();

        private static FavouritesDatabase INSTANCE;

        public static FavouritesDatabase getFavouritesDatabase(final Context context) {
            if (INSTANCE == null) {
                synchronized (FavouritesDatabase.class) {
                    if (INSTANCE == null) {
                        INSTANCE =
                                Room.databaseBuilder(
                                        context.getApplicationContext(),
                                        FavouritesDatabase.class,
                                        "favourites_database"
                                ).build();
                    }
                }
            }
            return INSTANCE;
        }
}

@Dao
public interface FavouritesDAO {

        @Query("SELECT * FROM favourites")
        LiveData<List<Favourites>> getAllFavourites();

        @Query("SELECT * FROM favourites")
        List<Favourites> loadAllFavorites();

        @Insert(onConflict = OnConflictStrategy.REPLACE)
        void insertAllFavourites(Favourites... favourites);

        @Insert(onConflict = OnConflictStrategy.REPLACE)
        public void insertFavourite(Favourites favourites);

        @Delete
        void delete(Favourites favourites);
}

    public void setUpUI(){

        recyclerView = findViewById(R.id.recycler_view_favourites);
        constraintLayoutEmpty = findViewById(R.id.constraint_empty);
        imageViewBack = findViewById(R.id.imageView_back);

        imageViewBack.setOnClickListener(this);



        favouritesViewModel = new ViewModelProvider(this,
                new FavouritesViewModelFactory(getApplication())).get(FavouritesViewModel.class);


        favouritesViewModel.getmAllFavourites().observe(this,
                new Observer<List<Favourites>>() {
            @Override
            public void onChanged(@Nullable final List<Favourites> products) {

                favouritesArrayList = products;
            }
        });
}

public LiveData<List<Favourites>> getAllFavourites() {
    return getAllFavourites();
}

public MutableLiveData<List<Favourites>> getFavouritesSearch() {
    return getFavouritesSearch();
}