Android Open Source - android-concurrent-database Database Manager

• Back to SQLite/Sample  ↑

From Project

Back to project page android-concurrent-database.

License

The source code is released under:

MIT License

Java Source Code

package com.dd.database;
/* w w  w. ja v a  2  s .c om*/

import com.dd.utils.L;

import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import java.util.concurrent.atomic.AtomicInteger;

public class DatabaseManager {

    private AtomicInteger mOpenCounter = new AtomicInteger();

    private static DatabaseManager instance;
    private SQLiteOpenHelper mDatabaseHelper;
    private SQLiteDatabase mDatabase;

    private DatabaseManager(SQLiteOpenHelper helper) {
        mDatabaseHelper = helper;
    }

    public static synchronized void initializeInstance(SQLiteOpenHelper helper) {
        if (instance == null) {
            instance = new DatabaseManager(helper);
        }
    }

    public static synchronized DatabaseManager getInstance() {
        if (instance == null) {
            throw new IllegalStateException(DatabaseManager.class.getSimpleName() +
                    " is not initialized, call initializeInstance(..) method first.");
        }

        return instance;
    }

    private synchronized SQLiteDatabase openDatabase() {
        if (mOpenCounter.incrementAndGet() == 1) {
            // Opening new database
            mDatabase = mDatabaseHelper.getWritableDatabase();
        }
        L.d("Database open counter: " + mOpenCounter.get());
        return mDatabase;
    }

    private synchronized void closeDatabase() {
        if (mOpenCounter.decrementAndGet() == 0) {
            // Closing database
            mDatabase.close();

        }
        L.d("Database open counter: " + mOpenCounter.get());
    }

    public void executeQuery(QueryExecutor executor) {
        SQLiteDatabase database = openDatabase();
        executor.run(database);
        closeDatabase();
    }

    public void executeQueryTask(final QueryExecutor executor) {
        new Thread(new Runnable() {
            @Override
            public void run() {
                SQLiteDatabase database = openDatabase();
                executor.run(database);
                closeDatabase();
            }
        }).start();
    }
}

Java Source Code List

• Back to SQLite/Sample  ↑