Java tutorial
/* * Copyright 2017-present Open Networking Laboratory * * 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.onosproject.mapping.impl; import com.google.common.collect.FluentIterable; import com.google.common.collect.Lists; import com.google.common.collect.Maps; import org.apache.felix.scr.annotations.Activate; import org.apache.felix.scr.annotations.Component; import org.apache.felix.scr.annotations.Deactivate; import org.apache.felix.scr.annotations.Modified; import org.apache.felix.scr.annotations.Service; import org.onosproject.mapping.DefaultMappingEntry; import org.onosproject.mapping.Mapping; import org.onosproject.mapping.MappingEntry; import org.onosproject.mapping.MappingEvent; import org.onosproject.mapping.MappingId; import org.onosproject.mapping.MappingStore; import org.onosproject.mapping.MappingStoreDelegate; import org.onosproject.mapping.StoredMappingEntry; import org.onosproject.net.DeviceId; import org.onosproject.store.AbstractStore; import org.osgi.service.component.ComponentContext; import org.slf4j.Logger; import java.util.Collections; import java.util.List; import java.util.concurrent.ConcurrentMap; import java.util.concurrent.CopyOnWriteArrayList; import static org.onosproject.mapping.MappingEntry.MappingEntryState.PENDING_ADD; import static org.onosproject.mapping.MappingEntry.MappingEntryState.PENDING_REMOVE; import static org.onosproject.mapping.MappingEvent.Type.MAPPING_ADDED; import static org.onosproject.mapping.MappingEvent.Type.MAPPING_REMOVED; import static org.onosproject.mapping.MappingEvent.Type.MAPPING_UPDATED; import static org.slf4j.LoggerFactory.getLogger; /** * Manages inventory of mappings using trivial in-memory implementation. */ @Component(immediate = true) @Service public class SimpleMappingStore extends AbstractStore<MappingEvent, MappingStoreDelegate> implements MappingStore { private final Logger log = getLogger(getClass()); private static final String UNRECOGNIZED_STORE_MSG = "Unrecognized store type {}"; private final ConcurrentMap<DeviceId, ConcurrentMap<MappingId, List<StoredMappingEntry>>> mapDbStore = Maps .newConcurrentMap(); private final ConcurrentMap<DeviceId, ConcurrentMap<MappingId, List<StoredMappingEntry>>> mapCacheStore = Maps .newConcurrentMap(); @Activate public void activate() { log.info("Started"); } @Deactivate public void deactivate() { mapDbStore.clear(); mapCacheStore.clear(); log.info("Stopped"); } @Modified public void modified(ComponentContext context) { } @Override public int getMappingCount(Type type) { int sum = 0; for (ConcurrentMap<MappingId, List<StoredMappingEntry>> mapDb : getMappingStore(type).values()) { for (List<StoredMappingEntry> mes : mapDb.values()) { sum += mes.size(); } } return sum; } @Override public Iterable<MappingEntry> getAllMappingEntries(Type type) { List<MappingEntry> entries = Lists.newArrayList(); for (ConcurrentMap<MappingId, List<StoredMappingEntry>> mapDb : getMappingStore(type).values()) { for (List<StoredMappingEntry> mes : mapDb.values()) { entries.addAll(mes); } } return entries; } /** * Obtains the mapping store for specified device and store type. * * @param type mapping store type * @param deviceId device identifier * @return Map representing Mapping Store of given device and store type */ private ConcurrentMap<MappingId, List<StoredMappingEntry>> getMappingStoreByDeviceId(Type type, DeviceId deviceId) { switch (type) { case MAP_DATABASE: return mapDbStore.computeIfAbsent(deviceId, k -> Maps.newConcurrentMap()); case MAP_CACHE: return mapCacheStore.computeIfAbsent(deviceId, k -> Maps.newConcurrentMap()); default: log.error(UNRECOGNIZED_STORE_MSG, type); return null; } } /** * Obtains the mapping store for specified store type. * * @param type mapping store type * @return mapping store */ private ConcurrentMap<DeviceId, ConcurrentMap<MappingId, List<StoredMappingEntry>>> getMappingStore(Type type) { switch (type) { case MAP_DATABASE: return mapDbStore; case MAP_CACHE: return mapCacheStore; default: log.error(UNRECOGNIZED_STORE_MSG, type); return null; } } /** * Obtains mapping entries for specified device, store type and mapping ID. * * @param type mapping store type * @param deviceId device identifier * @param mappingId mapping identifier * @return a collection of mapping entries */ private List<StoredMappingEntry> getMappingEntriesInternal(Type type, DeviceId deviceId, MappingId mappingId) { final ConcurrentMap<MappingId, List<StoredMappingEntry>> store = getMappingStoreByDeviceId(type, deviceId); List<StoredMappingEntry> r = store.get(mappingId); if (r == null) { final List<StoredMappingEntry> concurrentlyAdded; r = new CopyOnWriteArrayList<>(); concurrentlyAdded = store.putIfAbsent(mappingId, r); if (concurrentlyAdded != null) { return concurrentlyAdded; } } return r; } /** * Obtains a mapping entry for specified device, store type and mapping. * * @param type mapping store type * @param deviceId device identifier * @param mapping mapping identifier * @return a mapping entry */ private MappingEntry getMappingEntryInternal(Type type, DeviceId deviceId, Mapping mapping) { List<StoredMappingEntry> mes = getMappingEntriesInternal(type, deviceId, mapping.id()); for (StoredMappingEntry me : mes) { if (me.equals(mapping)) { return me; } } return null; } @Override public MappingEntry getMappingEntry(Type type, Mapping mapping) { return getMappingEntryInternal(type, mapping.deviceId(), mapping); } @Override public Iterable<MappingEntry> getMappingEntries(Type type, DeviceId deviceId) { // FIXME: a better way is using Java 8 API to return immutable iterables return FluentIterable.from(getMappingStoreByDeviceId(type, deviceId).values()) .transformAndConcat(Collections::unmodifiableList); } @Override public void storeMapping(Type type, Mapping mapping) { List<StoredMappingEntry> entries = getMappingEntriesInternal(type, mapping.deviceId(), mapping.id()); synchronized (entries) { if (!entries.contains(mapping)) { StoredMappingEntry entry = new DefaultMappingEntry(mapping); entries.add(entry); } } } @Override public void pendingDeleteMapping(Type type, Mapping mapping) { List<StoredMappingEntry> entries = getMappingEntriesInternal(type, mapping.deviceId(), mapping.id()); synchronized (entries) { for (StoredMappingEntry entry : entries) { if (entry.equals(mapping)) { synchronized (entry) { entry.setState(PENDING_REMOVE); } } } } } @Override public MappingEvent addOrUpdateMappingEntry(Type type, MappingEntry entry) { List<StoredMappingEntry> entries = getMappingEntriesInternal(type, entry.deviceId(), entry.id()); synchronized (entries) { for (StoredMappingEntry stored : entries) { if (stored.equals(entry)) { if (stored.state() == PENDING_ADD) { stored.setState(MappingEntry.MappingEntryState.ADDED); return new MappingEvent(MAPPING_ADDED, entry); } return new MappingEvent(MAPPING_UPDATED, entry); } } } log.error("Mapping was not found in store {} to update", entry); return null; } @Override public MappingEvent removeMapping(Type type, Mapping mapping) { List<StoredMappingEntry> entries = getMappingEntriesInternal(type, mapping.deviceId(), mapping.id()); synchronized (entries) { if (entries.remove(mapping)) { return new MappingEvent(MAPPING_REMOVED, mapping); } } return null; } @Override public MappingEvent pendingMappingEntry(Type type, MappingEntry entry) { List<StoredMappingEntry> entries = getMappingEntriesInternal(type, entry.deviceId(), entry.id()); synchronized (entries) { for (StoredMappingEntry stored : entries) { if (stored.equals(entry) && (stored.state() != PENDING_ADD)) { synchronized (stored) { stored.setState(PENDING_ADD); return new MappingEvent(MAPPING_UPDATED, entry); } } } } return null; } @Override public void purgeMappingEntry(Type type, DeviceId deviceId) { getMappingStore(type).remove(deviceId); } @Override public void purgeMappingEntries(Type type) { getMappingStore(type).clear(); } }