zack.examples.questiondb.database.QuestionsOpenHelper.java Source code

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Here is the source code for zack.examples.questiondb.database.QuestionsOpenHelper.java

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/**
 * Copyright 2014 Yehezkel (Zack) Yovel
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */
package zack.examples.questiondb.database;

import java.io.IOException;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;

public class QuestionsOpenHelper extends SQLiteOpenHelper {

    public static final String DB_CONTENT_URL = "https://raw.githubusercontent.com/ZackYovel/AndroidSqliteMultichoiceExample/master/sql/contents.sql";
    public static final String DB_NAME = "Questions.db";
    public static final int DB_VERSION = 1;
    private static final String TAG = "QuestionsOpenHelper";

    public QuestionsOpenHelper(Context context) {
        super(context, DB_NAME, null, DB_VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        // executing the schema - DDL (data definition language)
        db.execSQL(DBContract.QuestionsTable.SCHEMA);
        db.execSQL(DBContract.AnswersTable.SCHEMA);

        try {
            OkHttpClient client = new OkHttpClient();

            Request request = new Request.Builder().url(DB_CONTENT_URL).build();

            Response response = client.newCall(request).execute();
            String[] sql = response.body().string().split("===");

            // executing data insertion - DML (data manipulation language)
            for (String statement : sql) {
                db.execSQL(statement.trim());
            }

        } catch (IOException e) {
            e.printStackTrace();
            Log.d(TAG, e.getMessage());
        }

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // If the schema changes this is where you read data from the old table
        // defined by the old schema and adapt it to the new schema. Then
        // you re-create the table using the new schema and insert all data back
        // in.

        // in many tutorials they re-create the database here even if there is
        // nothing to change:
        db.execSQL(DBContract.QuestionsTable.DELETE_SCHEMA);
        db.execSQL(DBContract.AnswersTable.DELETE_SCHEMA);
        onCreate(db);
    }

}