Android SQLite Database Unit Testing

Question

I'm new to android app development and I just made a note app. I want to do unit tests for the insertNote, readNote and updateNote methods for the database. How do I go about this? This is the code for my database. Thanks.

public class  DatabaseManager extends SQLiteOpenHelper {


public static final String Database_Name = "Notes Database";
public static final String Table_Name = "notes";

public static final String Column_id = "textId";
public static final String Column_title = "textTitle";
public static final String Column_body = "textBody";

public DatabaseManager(Context context){
    super(context, Database_Name, null, 1);
}

@Override
public void onCreate(SQLiteDatabase db){
    db.execSQL("CREATE TABLE " + Table_Name + " (" + Column_id +
            " INTEGER PRIMARY KEY AUTOINCREMENT, " + Column_title +
            " TEXT, " + Column_body + " TEXT)");
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
    db.execSQL("DROP TABLE IF EXISTS" + Table_Name);
    onCreate(db);
}

public void insertNote(Note note){
    SQLiteDatabase db = this.getWritableDatabase();

    ContentValues values = new ContentValues();
    values.put(Column_title, note.getTextTitle());
    values.put(Column_body, note.getTextBody());

    boolean result = db.insert(Table_Name, null, values) > 0;
    if (result == true)
        Log.d("Create", "Data Has Been Saved");
    db.close();
}

public Cursor readNote(int id){
    SQLiteDatabase db = this.getReadableDatabase();

    Cursor cursor = db.rawQuery("SELECT * FROM " + Table_Name + " WHERE _ROWID_ = " + id, null);

    if (cursor != null){
        cursor.moveToFirst();
    }

    Note myNote = new Note();
    myNote.textId = cursor.getInt(cursor.getColumnIndex(Column_id));
    myNote.textTitle = cursor.getString(cursor.getColumnIndex(Column_title));

    return cursor;
}

public ArrayList<String> getNoteList(){
    ArrayList<String> noteList =  new ArrayList<>();
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery("SELECT * FROM " + Table_Name, null);
    cursor.moveToFirst();

    if (cursor.moveToFirst()){
        do{
            //noteList.add(cursor.getInt(cursor.getColumnIndex(Column_id)));
            noteList.add(cursor.getString(cursor.getColumnIndex(Column_title)));
        }
        while (cursor.moveToNext());
    }

    return noteList;
}

public int updateNote(Note note){
    SQLiteDatabase db = this.getWritableDatabase();

    ContentValues values = new ContentValues();
    values.put("textTitle", note.getTextTitle());
    values.put("textBody", note.getTextBody());

    int update = db.update(Table_Name, values, Column_id + " = ?", new String[]{Integer.toString(note.getTextId())});
    return update;
}

public Integer deleteNote(int id){
    SQLiteDatabase db = this.getWritableDatabase();
   return db.delete(Table_Name, Column_id + " = ?", new String[]{Integer.toString(id)} );
}

public int getCount(){
    SQLiteDatabase db = this.getReadableDatabase();
    Cursor cursor = db.rawQuery("SELECT * FROM " + Table_Name, null);
    cursor.close();

    return cursor.getCount();
}

}

Answer 1

One way to implement SQLite testing is with an instrumented unit test, using the InstrumentationRegistry in the Android test package to obtain a Context.

Here is an example from a tutorial and an example on GitHub:

import android.support.test.InstrumentationRegistry;
import android.support.test.runner.AndroidJUnit4;
import android.test.suitebuilder.annotation.LargeTest;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;

import java.util.List;

import static junit.framework.Assert.assertNotNull;
import static junit.framework.Assert.assertTrue;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.MatcherAssert.assertThat;

@RunWith(AndroidJUnit4.class)
@LargeTest
public class SQLiteTest {

    private RateDataSource mDataSource;

    @Before
    public void setUp(){
        mDataSource = new RateDataSource(InstrumentationRegistry.getTargetContext());
        mDataSource.open();
    }

    @After
    public void finish() {
        mDataSource.close();
    }

    @Test
    public void testPreConditions() {
        assertNotNull(mDataSource);
    }

    @Test
    public void testShouldAddExpenseType() throws Exception {
        mDataSource.createRate("AUD", 1.2);
        List<Rate> rate = mDataSource.getAllRates();

        assertThat(rate.size(), is(1));
        assertTrue(rate.get(0).toString().equals("AUD"));
        assertTrue(rate.get(0).getValue().equals(1.2));
    }

    @Test
    public void testDeleteAll() {
        mDataSource.deleteAll();
        List<Rate> rate = mDataSource.getAllRates();

        assertThat(rate.size(), is(0));
    }

    @Test
    public void testDeleteOnlyOne() {
        mDataSource.createRate("AUD", 1.2);
        List<Rate> rate = mDataSource.getAllRates();

        assertThat(rate.size(), is(1));

        mDataSource.deleteRate(rate.get(0));
        rate = mDataSource.getAllRates();

        assertThat(rate.size(), is(0));
    }

    @Test
    public void testAddAndDelete() {
        mDataSource.deleteAll();
        mDataSource.createRate("AUD", 1.2);
        mDataSource.createRate("JPY", 1.993);
        mDataSource.createRate("BGN", 1.66);

        List<Rate> rate = mDataSource.getAllRates();
        assertThat(rate.size(), is(3));

        mDataSource.deleteRate(rate.get(0));
        mDataSource.deleteRate(rate.get(1));

        rate = mDataSource.getAllRates();
        assertThat(rate.size(), is(1));
    }
}