Java tutorial
/* * Copyright (C) 2011 4th Line GmbH, Switzerland * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * This program 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 Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.fourthline.konto.client; import com.google.gwt.activity.shared.Activity; import com.google.gwt.activity.shared.ActivityMapper; import com.google.web.bindery.event.shared.EventBus; import com.google.gwt.place.shared.Place; import com.google.gwt.place.shared.PlaceHistoryMapper; import com.google.gwt.place.shared.WithTokenizers; import javax.inject.Inject; import com.google.inject.Provider; import org.fourthline.konto.client.currency.CurrencyActivity; import org.fourthline.konto.client.currency.CurrencyPlace; import org.fourthline.konto.client.dashboard.DashboardActivity; import org.fourthline.konto.client.dashboard.DashboardPlace; import org.fourthline.konto.client.ledger.LedgerActivity; import org.fourthline.konto.client.ledger.LedgerPlace; import org.fourthline.konto.client.ledger.account.AccountActivity; import org.fourthline.konto.client.ledger.account.AccountPlace; import org.fourthline.konto.client.main.MainPresenter; import org.seamless.gwt.notify.client.Notifications; import org.seamless.gwt.notify.client.NotifyEvent; import org.fourthline.konto.client.report.ReportActivity; import org.fourthline.konto.client.report.ReportPlace; import org.fourthline.konto.client.settings.SettingsActivity; import org.fourthline.konto.client.settings.SettingsPlace; /** * These are two mapping layers of the MVP navigation system in GWT 2.1. * <p> * Yes, this is shockingly bad. I understand that strings * suck and you want to avoid string-keyed maps. I also understand * the limitations of no reflection and GWT rebinding. What I don't * understand is how you can't see that you are on the wrong track * if your design results in names like * "ActivityFactoryMapperFactoryManagerProvider". Hired any Spring * guys recently? You need to ask yourself why you are doing all * of this. Nobody believes you are trying to improve testability * here, the bugs you introduce with these layers of junk will * never be tested. * </p> * <p> * The problem you are trying to solve is really simple: The first * mapping layer has to map 1:1 between a URL fragment and a Place * instance. The second layer maps Place n:1 Activity. Now, even * if you want to expose URL rewriters, URL manipulators, * and other APIs that allow more fine-grained control of these * mapping procedures, I doubt it has to be as ugly as it is now. * </p> * * @author Christian Bauer */ public class NavigationMapper implements ActivityMapper { @WithTokenizers({ DashboardPlace.Tokenizer.class, LedgerPlace.Tokenizer.class, AccountPlace.Tokenizer.class, CurrencyPlace.Tokenizer.class, ReportPlace.Tokenizer.class, SettingsPlace.Tokenizer.class }) static public interface History extends PlaceHistoryMapper { } final MainPresenter mainPresenter; final Provider<DashboardActivity> dashboardActivityProvider; final Provider<LedgerActivity> ledgerActivityProvider; final Provider<AccountActivity> accountActivityProvider; final Provider<CurrencyActivity> currencyActivityProvider; final Provider<ReportActivity> reportActivityProvider; final Provider<SettingsActivity> settingsActivityProvider; @Inject public NavigationMapper(MainPresenter mainPresenter, Provider<DashboardActivity> dashboardActivityProvider, Provider<LedgerActivity> ledgerActivityProvider, Provider<AccountActivity> accountActivityProvider, Provider<CurrencyActivity> currencyActivityProvider, Provider<ReportActivity> reportActivityProvider, Provider<SettingsActivity> settingsActivityProvider, EventBus bus, Notifications notifications) { super(); this.mainPresenter = mainPresenter; this.dashboardActivityProvider = dashboardActivityProvider; this.ledgerActivityProvider = ledgerActivityProvider; this.accountActivityProvider = accountActivityProvider; this.currencyActivityProvider = currencyActivityProvider; this.reportActivityProvider = reportActivityProvider; this.settingsActivityProvider = settingsActivityProvider; bus.addHandler(NotifyEvent.TYPE, notifications); } @Override public Activity getActivity(Place place) { if (place instanceof DashboardPlace) { return dashboardActivityProvider.get().init((DashboardPlace) place); } else if (place instanceof LedgerPlace) { return ledgerActivityProvider.get().init((LedgerPlace) place); } else if (place instanceof AccountPlace) { return accountActivityProvider.get().init((AccountPlace) place); } else if (place instanceof CurrencyPlace) { return currencyActivityProvider.get().init((CurrencyPlace) place); } else if (place instanceof ReportPlace) { return reportActivityProvider.get().init((ReportPlace) place); } else if (place instanceof SettingsPlace) { return settingsActivityProvider.get().init((SettingsPlace) place); } return null; } }