FanDatabase.java

package com.ch_linghu.fanfoudroid.db2;

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

import com.ch_linghu.fanfoudroid.db2.FanContent.*;

public class FanDatabase {
	private static final String TAG = FanDatabase.class.getSimpleName();

	/**
	 * SQLite Database file name
	 */
	private static final String DATABASE_NAME = "fanfoudroid.db";

	/**
	 * Database Version
	 */
	public static final int DATABASE_VERSION = 2;

	/**
	 * self instance
	 */
	private static FanDatabase sInstance = null;

	/**
	 * SQLiteDatabase Open Helper
	 */
	private DatabaseHelper mOpenHelper = null;

	/**
	 * SQLiteOpenHelper
	 */
	private static class DatabaseHelper extends SQLiteOpenHelper {

		// Construct
		public DatabaseHelper(Context context) {
			super(context, DATABASE_NAME, null, DATABASE_VERSION);
		}

		@Override
		public void onCreate(SQLiteDatabase db) {
			Log.d(TAG, "Create Database.");
			// TODO: create tables
			createAllTables(db);
			createAllIndexes(db);
		}

		@Override
		public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
			Log.d(TAG, "Upgrade Database.");
			// TODO: DROP TABLE
			onCreate(db);
		}

	}

	/**
	 * Construct
	 * 
	 * @param context
	 */
	private FanDatabase(Context context) {
		mOpenHelper = new DatabaseHelper(context);
	}

	/**
	 * Get Database
	 * 
	 * @param context
	 * @return
	 */
	public static synchronized FanDatabase getInstance(Context context) {
		if (null == sInstance) {
			sInstance = new FanDatabase(context);
		}
		return sInstance;
	}

	/**
	 * Get SQLiteDatabase Open Helper
	 * 
	 * @return
	 */
	public SQLiteOpenHelper getSQLiteOpenHelper() {
		return mOpenHelper;
	}

	/**
	 * Get Database Connection
	 * 
	 * @param writeable
	 * @return
	 */
	public SQLiteDatabase getDb(boolean writeable) {
		if (writeable) {
			return mOpenHelper.getWritableDatabase();
		} else {
			return mOpenHelper.getReadableDatabase();
		}
	}

	/**
	 * Close Database
	 */
	public void close() {
		if (null != sInstance) {
			mOpenHelper.close();
			sInstance = null;
		}
	}

	// Create All tables
	private static void createAllTables(SQLiteDatabase db) {
		db.execSQL(StatusesTable.getCreateSQL());
		db.execSQL(StatusesPropertyTable.getCreateSQL());
		db.execSQL(UserTable.getCreateSQL());
		db.execSQL(DirectMessageTable.getCreateSQL());
		db.execSQL(FollowRelationshipTable.getCreateSQL());
		db.execSQL(TrendTable.getCreateSQL());
		db.execSQL(SavedSearchTable.getCreateSQL());
	}

	private static void dropAllTables(SQLiteDatabase db) {
		db.execSQL(StatusesTable.getDropSQL());
		db.execSQL(StatusesPropertyTable.getDropSQL());
		db.execSQL(UserTable.getDropSQL());
		db.execSQL(DirectMessageTable.getDropSQL());
		db.execSQL(FollowRelationshipTable.getDropSQL());
		db.execSQL(TrendTable.getDropSQL());
		db.execSQL(SavedSearchTable.getDropSQL());
	}

	private static void resetAllTables(SQLiteDatabase db, int oldVersion,
			int newVersion) {
		try {
			dropAllTables(db);
		} catch (SQLException e) {
			Log.e(TAG, "resetAllTables ERROR!");
		}
		createAllTables(db);
	}

	// indexes
	private static void createAllIndexes(SQLiteDatabase db) {
		db.execSQL(StatusesTable.getCreateIndexSQL());
	}
}