/* * Copyright 2017 Anton Tananaev (anton@traccar.org) * Copyright 2017 Andrey Kunitsyn (andrey@traccar.org) * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.traccar.database; import java.sql.SQLException; import java.util.Collection; import java.util.HashSet; import java.util.LinkedList; import java.util.Map; import java.util.Set; import java.util.concurrent.ConcurrentHashMap; import org.traccar.helper.Log; import org.traccar.model.BaseModel; public class BaseObjectManager<T extends BaseModel> { private final DataManager dataManager; private Map<Long, T> items; private Class<T> baseClass; protected BaseObjectManager(DataManager dataManager, Class<T> baseClass) { this.dataManager = dataManager; this.baseClass = baseClass; refreshItems(); } protected final DataManager getDataManager() { return dataManager; } protected final Class<T> getBaseClass() { return baseClass; } public T getById(long itemId) { return items.get(itemId); } public void refreshItems() { if (dataManager != null) { try { Collection<T> databaseItems = dataManager.getObjects(baseClass); if (items == null) { items = new ConcurrentHashMap<>(databaseItems.size()); } Set<Long> databaseItemIds = new HashSet<>(); for (T item : databaseItems) { databaseItemIds.add(item.getId()); if (items.containsKey(item.getId())) { updateCachedItem(item); } else { addNewItem(item); } } for (Long cachedItemId : items.keySet()) { if (!databaseItemIds.contains(cachedItemId)) { removeCachedItem(cachedItemId); } } } catch (SQLException error) { Log.warning(error); } } } protected void addNewItem(T item) { items.put(item.getId(), item); } public void addItem(T item) throws SQLException { dataManager.addObject(item); addNewItem(item); } protected void updateCachedItem(T item) { items.put(item.getId(), item); } public void updateItem(T item) throws SQLException { dataManager.updateObject(item); updateCachedItem(item); } protected void removeCachedItem(long itemId) { items.remove(itemId); } public void removeItem(long itemId) throws SQLException { BaseModel item = getById(itemId); if (item != null) { dataManager.removeObject(baseClass, itemId); removeCachedItem(itemId); } } public final Collection<T> getItems(Set<Long> itemIds) { Collection<T> result = new LinkedList<>(); for (long itemId : itemIds) { result.add(getById(itemId)); } return result; } public Set<Long> getAllItems() { return items.keySet(); } }