A BaseDao interface that provides the methods needed for inserting, updating & deleting an entity in a Room Dao interface.

BaseDao.java

package com.example.app.data.local.dao;

import androidx.room.Delete;
import androidx.room.Insert;
import androidx.room.OnConflictStrategy;
import androidx.room.Update;

import java.util.List;

/**
 * Provides the methods needed for inserting, updating & deleting an entity in a Room Dao interface.
 * <br>
 * Make your Room Dao interface extends this BaseInterface setting the generic type as the entity 
 * class. If you need to specify custom attributes on the Dao methods, just override
 * them in your Dao.
 *
 * @param <T> the entity class.
 * @author Abdallah Abdelazim
 */
public interface BaseDao<T> {

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    long insert(T obj);

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    long[] insert(T[] objs);

    @Insert(onConflict = OnConflictStrategy.REPLACE)
    long[] insert(List<? extends T> objList);

    @Update
    int update(T obj);

    @Update
    int update(T[] objs);

    @Update
    int update(List<? extends T> objList);

    @Delete
    int delete(T obj);

    @Delete
    int delete(T[] objs);

    @Delete
    int delete(List<? extends T> objList);
}