AvatarTable.java

/**
 * Copyright (c) 2013, Redsolution LTD. All rights reserved.
 *
 * This file is part of Xabber project; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License, Version 3.
 *
 * Xabber is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License,
 * along with this program. If not, see http://www.gnu.org/licenses/.
 */
package com.xabber.android.data.database.sqlite;

import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteStatement;
import android.provider.BaseColumns;

import com.xabber.android.data.database.DatabaseManager;

/**
 * Storage with avatar hashes for the users.
 *
 * @author alexander.ivanov
 */
public class AvatarTable extends AbstractTable {

    private static final class Fields implements BaseColumns {
        private Fields() {
        }

        public static final String USER = "user";
        public static final String HASH = "hash";
    }

    private static final String NAME = "avatars";
    private static final String[] PROJECTION = new String[]{Fields.USER,
            Fields.HASH,};

    private final DatabaseManager databaseManager;
    private SQLiteStatement writeStatement;
    private final Object writeLock;

    private static AvatarTable instance;

    public static AvatarTable getInstance() {
        if (instance == null) {
            instance = new AvatarTable(DatabaseManager.getInstance());
        }

        return instance;
    }

    private AvatarTable(DatabaseManager databaseManager) {
        this.databaseManager = databaseManager;
        writeStatement = null;
        writeLock = new Object();
    }

    @Override
    public void create(SQLiteDatabase db) {
        String sql = "CREATE TABLE " + NAME + " (" + Fields.USER
                + " TEXT PRIMARY KEY," + Fields.HASH + " TEXT);";
        DatabaseManager.execSQL(db, sql);
    }

    @Override
    public void migrate(SQLiteDatabase db, int toVersion) {
        super.migrate(db, toVersion);
        switch (toVersion) {
            case 2:
                String sql = "CREATE TABLE avatars (" + "user TEXT PRIMARY KEY,"
                        + "hash TEXT);";
                DatabaseManager.execSQL(db, sql);
                break;
            default:
                break;
        }
    }

    /**
     * Saves avatar's hash for user.
     *
     * @param bareAddress
     * @param hash
     */
    public void write(String bareAddress, String hash) {
        synchronized (writeLock) {
            if (writeStatement == null) {
                SQLiteDatabase db = databaseManager.getWritableDatabase();
                writeStatement = db.compileStatement("INSERT OR REPLACE INTO "
                        + NAME + " (" + Fields.USER + ", " + Fields.HASH
                        + ") VALUES (?, ?);");
            }
            writeStatement.bindString(1, bareAddress);
            if (hash == null)
                writeStatement.bindNull(2);
            else
                writeStatement.bindString(2, hash);
            writeStatement.execute();
        }
    }

    @Override
    protected String getTableName() {
        return NAME;
    }

    @Override
    protected String[] getProjection() {
        return PROJECTION;
    }

    public static String getUser(Cursor cursor) {
        return cursor.getString(cursor.getColumnIndex(Fields.USER));
    }

    public static String getHash(Cursor cursor) {
        return cursor.getString(cursor.getColumnIndex(Fields.HASH));
    }

}