如何将这些对象存储在SQLite数据库中？

Question

So I have a class named A:

public class A{
    private String A1;
    private String A2;
    private String A3;
    private String A4;
    private B A5;
    private B A6;
}

That as you can see contains some strings and 2 B class typed object. The B class:

public class B{
    private ArrayList<C> B1;
}

Contains 1 arraylist of C elements. The C class:

public class C{
    private String C1;
    private ArrayList<D> C2;

A string and arraylist of D objects. The D class:

public class D{
    private String D1;
    private Boolean D2;
}

I get the data from JSON files, I build up an arraylist out of A objects, but I should store it in a database because I do not want to download the data every time the user opens the application...

Answer 1

You are attempting to store non-atomic values into a relational database. You must normalize it using multiple tables which relate to each other using foreign keys. Quite a tedious task to do.

Perhaps you can store the object itself using serialization - resource

Answer 2

You just want to store the custom model object into a database so for this you can use room Persistence database by Google. Check the following link: local database using Roome