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1package com.mochamadahya.notesapp;
2
3import android.content.ContentValues;
4import android.content.Context;
5import android.database.Cursor;
6import android.database.sqlite.SQLiteDatabase;
7import android.database.sqlite.SQLiteOpenHelper;
8
9import java.util.ArrayList;
10import java.util.List;
11
12public class DatabaseHelper extends SQLiteOpenHelper {
13    // Database Version
14    private static final int DATABASE_VERSION = 1;
15
16    // Database Name
17    private static final String DATABASE_NAME = "notes_db";
18
19
20    public DatabaseHelper(Context context) {
21        super(context, DATABASE_NAME, null, DATABASE_VERSION);
22    }
23
24    // Creating Tables
25    @Override
26    public void onCreate(SQLiteDatabase db) {
27
28        // create notes table
29        db.execSQL(Note.CREATE_TABLE);
30    }
31
32    // Upgrading database
33    @Override
34    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
35        // Drop older table if existed
36        db.execSQL("DROP TABLE IF EXISTS " + Note.TABLE_NAME);
37
38        // Create tables again
39        onCreate(db);
40    }
41    public long insertNote(String note) {
42        // get writable database as we want to write data
43        SQLiteDatabase db = this.getWritableDatabase();
44
45        ContentValues values = new ContentValues();
46        // `id` and `timestamp` will be inserted automatically.
47        // no need to add them
48        values.put(Note.COLUMN_NOTE, note);
49
50        // insert row
51        long id = db.insert(Note.TABLE_NAME, null, values);
52
53        // close db connection
54        db.close();
55
56        // return newly inserted row id
57        return id;
58    }
59
60    public Note getNote(long id) {
61        // get readable database as we are not inserting anything
62        SQLiteDatabase db = this.getReadableDatabase();
63
64        Cursor cursor = db.query(Note.TABLE_NAME,
65                new String[]{Note.COLUMN_ID, Note.COLUMN_NOTE, Note.COLUMN_TIMESTAMP},
66                Note.COLUMN_ID + "=?",
67                new String[]{String.valueOf(id)}, null, null, null, null);
68
69        if (cursor != null)
70            cursor.moveToFirst();
71
72        // prepare note object
73        Note note = new Note(
74                cursor.getInt(cursor.getColumnIndex(Note.COLUMN_ID)),
75                cursor.getString(cursor.getColumnIndex(Note.COLUMN_NOTE)),
76                cursor.getString(cursor.getColumnIndex(Note.COLUMN_TIMESTAMP)));
77
78        // close the db connection
79        cursor.close();
80
81        return note;
82    }
83
84    public List<Note> getAllNotes() {
85        List<Note> notes = new ArrayList<>();
86
87        // Select All Query
88        String selectQuery = "SELECT  * FROM " + Note.TABLE_NAME + " ORDER BY " +
89                Note.COLUMN_TIMESTAMP + " DESC";
90
91        SQLiteDatabase db = this.getWritableDatabase();
92        Cursor cursor = db.rawQuery(selectQuery, null);
93
94        // looping through all rows and adding to list
95        if (cursor.moveToFirst()) {
96            do {
97                Note note = new Note();
98                note.setId(cursor.getInt(cursor.getColumnIndex(Note.COLUMN_ID)));
99                note.setNote(cursor.getString(cursor.getColumnIndex(Note.COLUMN_NOTE)));
100                note.setTimestamp(cursor.getString(cursor.getColumnIndex(Note.COLUMN_TIMESTAMP)));
101
102                notes.add(note);
103            } while (cursor.moveToNext());
104        }
105
106        // close db connection
107        db.close();
108
109        // return notes list
110        return notes;
111    }
112
113    public int getNotesCount() {
114        String countQuery = "SELECT  * FROM " + Note.TABLE_NAME;
115        SQLiteDatabase db = this.getReadableDatabase();
116        Cursor cursor = db.rawQuery(countQuery, null);
117
118        int count = cursor.getCount();
119        cursor.close();
120
121
122        // return count
123        return count;
124    }
125
126    public int updateNote(Note note) {
127        SQLiteDatabase db = this.getWritableDatabase();
128
129        ContentValues values = new ContentValues();
130        values.put(Note.COLUMN_NOTE, note.getNote());
131
132        // updating row
133        return db.update(Note.TABLE_NAME, values, Note.COLUMN_ID + " = ?",
134                new String[]{String.valueOf(note.getId())});
135    }
136
137    public void deleteNote(Note note) {
138        SQLiteDatabase db = this.getWritableDatabase();
139        db.delete(Note.TABLE_NAME, Note.COLUMN_ID + " = ?",
140                new String[]{String.valueOf(note.getId())});
141        db.close();
142    }
143
144}