DatabaseFactory.java

package com.badlogic.gdx.sql;

import java.util.List;

import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.utils.GdxRuntimeException;

/**
 * A factory class that creates new database objects and returns references to
 * them. See {@link DatabaseFactory#getNewDatabase(String, int, String, String)}
 * for more details.
 * 
 * @author M Rafay Aleem
 */
public class DatabaseFactory {
    
    public static final String ERROR_TAG = "DATABASE";
    private static final String androidClassname = "com.badlogic.gdx.sqlite.android.AndroidDatabaseManager";
    private static final String desktopClassname = "com.badlogic.gdx.sqlite.desktop.DesktopDatabaseManager";
    private static final String iosClassname = "de.fau.cs.mad.fly.ios.sqlite.IOSDatabaseManager";
    
    private static DatabaseManager databaseManager = null;
    
    /**
     * This is a factory method that will return a reference to an existing or a
     * not-yet-created database. You will need to manually call methods on the
     * {@link Database} object to setup, open/create or close the database. See
     * {@link Database} for more details. <b> Note: </b> dbOnUpgradeQuery will
     * only work on an Android device. It will be executed when you increment
     * your database version number. First, dbOnUpgradeQuery will be executed
     * (Where you will generally perform activities such as dropping the tables,
     * etc.). Then dbOnCreateQuery will be executed. However, dbOnUpgradeQuery
     * won't be executed on downgrading the database version.
     * 
     * @param dbName
     *            The name of the database.
     * @param dbVersion
     *            number of the database (starting at 1); if the database is
     *            older, dbOnUpgradeQuery will be used to upgrade the database
     *            (on Android only)
     * @param dbOnCreateQuery
     *            The query that should be executed on the creation of the
     *            database. This query would usually create the necessary tables
     *            in the database.
     * @param dbOnUpgradeQuery
     *            The query that should be executed on upgrading the database
     *            from an old version to a new one.
     * @return Returns a {@link Database} object pointing to an existing or
     *         not-yet-created database.
     */
    public static Database getNewDatabase(String dbName, int dbVersion, List<String> dbOnCreateQuery, List<String> dbOnUpgradeQuery) {
        if (databaseManager == null) {
            switch (Gdx.app.getType()) {
            case Android:
                try {
                    databaseManager = (DatabaseManager) Class.forName(androidClassname).newInstance();
                } catch (Exception ex) {
                    throw new GdxRuntimeException("Error getting database: " + androidClassname, ex);
                }
                break;
            case Desktop:
                try {
                    databaseManager = (DatabaseManager) Class.forName(desktopClassname).newInstance();
                } catch (Exception ex) {
                    throw new GdxRuntimeException("Error getting database: " + desktopClassname, ex);
                }
                break;
            case Applet:
                throw new GdxRuntimeException("SQLite is currently not supported in Applets by this libgdx extension.");
            case WebGL:
                throw new GdxRuntimeException("SQLite is currently not supported in WebGL by this libgdx extension.");
            case iOS:
                try {
                    databaseManager = (DatabaseManager) Class.forName(iosClassname).newInstance();
                } catch (Exception ex) {
                    throw new GdxRuntimeException("Error getting database: " + iosClassname, ex);
                }
                break;
            default:
                throw new GdxRuntimeException("SQLite is currently not supported in " + Gdx.app.getType() + " by this libgdx extension.");
                
            }
        }
        return databaseManager.getNewDatabase(dbName, dbVersion, dbOnCreateQuery, dbOnUpgradeQuery);
    }
    
    private DatabaseFactory() {
    }
    
}