1.依赖包

implementation 'com.google.code.gson:gson:2.6.2'
//加密
    implementation "net.zetetic:android-database-sqlcipher:4.3.0@aar"
    implementation "androidx.sqlite:sqlite:2.0.1"

2.model

@Entity
public class GoodsModel implements Parcelable {
    @Id(autoincrement = true)
    private Long id;
    private Integer goodsId;
    private String name;
    private String icon;
    private String info;
    private String type;

build --> make module
生成DaoMaster,DaoSession,GoodsModelDao
3.myApplication

public class MyApplication extends Application {

    public static DaoSession mDaoSession;

    @Override
    public void onCreate() {
        super.onCreate();

        initDb();
    }

    public void initDb() {
        //1.获取需要连接的数据库
        DaoMaster.DevOpenHelper devOpenHelper = new DaoMaster.DevOpenHelper(this, "goods2.db");
        //SQLiteDatabase database = devOpenHelper.getWritableDatabase();
        //加密
        Database database = devOpenHelper.getEncryptedWritableDb("123456");
        //2.创建数据库连接
        DaoMaster daoMaster = new DaoMaster(database);
        //3.创建数据库会话

        mDaoSession = daoMaster.newSession();
    }
}

manifest 注册
4.GreenDaoManager

public class GreenDaoManager {
    private Context mContext;
    private GoodsModelDao goodsModelDao;

    public GreenDaoManager(Context mContext) {
        this.mContext = mContext;
        goodsModelDao = MyApplication.mDaoSession.getGoodsModelDao();
    }

    //添加所有数据到数据库
    public void insertGoods() {
        String goodsJson = DataUtil.getJSon("goods.json", mContext);
        ArrayList<GoodsModel> goodsModels=DataUtil.getGoodList(goodsJson);
        goodsModelDao.insertInTx(goodsModels);
    }

    //查询所有数据
    public ArrayList<GoodsModel> queryGoods(){
        QueryBuilder<GoodsModel> queryBuilder=goodsModelDao.queryBuilder()
                .orderAsc(GoodsModelDao.Properties.GoodsId);
        return (ArrayList<GoodsModel>) queryBuilder.list();
    }

    //查询所有水果
    public ArrayList<GoodsModel> queryFruits(){
        QueryBuilder<GoodsModel> queryBuilder=goodsModelDao.queryBuilder()
                .where(GoodsModelDao.Properties.Type.eq(0))
                .orderAsc(GoodsModelDao.Properties.GoodsId);
        return (ArrayList<GoodsModel>) queryBuilder.list();
    }

    //查询所有零食
    public ArrayList<GoodsModel> querySnacks(){
        QueryBuilder<GoodsModel> queryBuilder=goodsModelDao.queryBuilder()
                .where(GoodsModelDao.Properties.Type.eq(1))
                .orderAsc(GoodsModelDao.Properties.GoodsId);
        return (ArrayList<GoodsModel>) queryBuilder.list();
    }

    //删除一条数据
    public void deleteGood(GoodsModel model){
        goodsModelDao.delete(model);
    }

    //修改数据
    public void updateGood(GoodsModel model){
        goodsModelDao.update(model);
    }

}

5.使用

private GreenDaoManager greenDaoManager;
greenDaoManager = new GreenDaoManager(this);
  
 public void myClick(View view) {
        switch (view.getId()) {
            case R.id.add_goods_btn:
                greenDaoManager.insertGoods();
                break;
            case R.id.all_goods_btn:
                goodsModels=greenDaoManager.queryGoods();
                adapter.setGoodsList(goodsModels);
                break;
            case R.id.fruit_goods_btn:
                goodsModels=greenDaoManager.queryFruits();
                adapter.setGoodsList(goodsModels);
                break;
            case R.id.snack_goods_btn:
                goodsModels=greenDaoManager.querySnacks();
                adapter.setGoodsList(goodsModels);
                break;
        }
    }

  
    private void addEvents() {
        updateGoodsBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String info=goodDetalEt.getText().toString();
                goods.setInfo(info);
                greenDaoManager.updateGood(goods);
                onBackPressed();
            }
        });

        removeGoodsBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                AlertDialog.Builder builder=new AlertDialog.Builder(GoodsDetailActivity.this);
                builder.setMessage("确认删除？");
                builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        greenDaoManager.deleteGood(goods);
                        finish();
                    }
                });
                builder.setNegativeButton("取消",null);
                builder.show();
            }
        });
    }