Java tutorial
/* * Copyright 2016-present Open Networking Foundation * * 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 io.atomix.core.map.impl; import com.google.common.collect.ImmutableMap; import com.google.common.collect.Maps; import io.atomix.core.collection.AsyncDistributedCollection; import io.atomix.core.collection.impl.TranscodingAsyncDistributedCollection; import io.atomix.core.map.AsyncAtomicMap; import io.atomix.core.map.AtomicMap; import io.atomix.core.map.AtomicMapEvent; import io.atomix.core.map.AtomicMapEventListener; import io.atomix.core.set.AsyncDistributedSet; import io.atomix.core.set.impl.TranscodingAsyncDistributedSet; import io.atomix.core.transaction.TransactionId; import io.atomix.core.transaction.TransactionLog; import io.atomix.primitive.impl.DelegatingAsyncPrimitive; import io.atomix.utils.concurrent.Futures; import io.atomix.utils.time.Versioned; import java.time.Duration; import java.util.HashSet; import java.util.Map; import java.util.Map.Entry; import java.util.Set; import java.util.concurrent.CompletableFuture; import java.util.concurrent.Executor; import java.util.function.BiFunction; import java.util.function.Function; import java.util.function.Predicate; import java.util.stream.Collectors; /** * An {@code AsyncConsistentMap} that maps its operations to operations on a * differently typed {@code AsyncConsistentMap} by transcoding operation inputs and outputs. * * @param <K2> key type of other map * @param <V2> value type of other map * @param <K1> key type of this map * @param <V1> value type of this map */ public class TranscodingAsyncAtomicMap<K1, V1, K2, V2> extends DelegatingAsyncPrimitive implements AsyncAtomicMap<K1, V1> { private final AsyncAtomicMap<K2, V2> backingMap; protected final Function<K1, K2> keyEncoder; protected final Function<K2, K1> keyDecoder; protected final Function<V2, V1> valueDecoder; protected final Function<V1, V2> valueEncoder; protected final Function<Versioned<V2>, Versioned<V1>> versionedValueDecoder; protected final Function<Versioned<V1>, Versioned<V2>> versionedValueEncoder; protected final Function<Entry<K2, Versioned<V2>>, Entry<K1, Versioned<V1>>> entryDecoder; protected final Function<Entry<K1, Versioned<V1>>, Entry<K2, Versioned<V2>>> entryEncoder; private final Map<AtomicMapEventListener<K1, V1>, InternalBackingAtomicMapEventListener> listeners = Maps .newIdentityHashMap(); public TranscodingAsyncAtomicMap(AsyncAtomicMap<K2, V2> backingMap, Function<K1, K2> keyEncoder, Function<K2, K1> keyDecoder, Function<V1, V2> valueEncoder, Function<V2, V1> valueDecoder) { super(backingMap); this.backingMap = backingMap; this.keyEncoder = k -> k == null ? null : keyEncoder.apply(k); this.keyDecoder = k -> k == null ? null : keyDecoder.apply(k); this.valueEncoder = v -> v == null ? null : valueEncoder.apply(v); this.valueDecoder = v -> v == null ? null : valueDecoder.apply(v); this.versionedValueDecoder = v -> v == null ? null : v.map(valueDecoder); this.versionedValueEncoder = v -> v == null ? null : v.map(valueEncoder); this.entryDecoder = e -> e == null ? null : Maps.immutableEntry(keyDecoder.apply(e.getKey()), versionedValueDecoder.apply(e.getValue())); this.entryEncoder = e -> e == null ? null : Maps.immutableEntry(keyEncoder.apply(e.getKey()), versionedValueEncoder.apply(e.getValue())); } @Override public CompletableFuture<Integer> size() { return backingMap.size(); } @Override public CompletableFuture<Boolean> containsKey(K1 key) { try { return backingMap.containsKey(keyEncoder.apply(key)); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Boolean> containsValue(V1 value) { try { return backingMap.containsValue(valueEncoder.apply(value)); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> get(K1 key) { try { return backingMap.get(keyEncoder.apply(key)).thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Map<K1, Versioned<V1>>> getAllPresent(Iterable<K1> keys) { try { Set<K2> uniqueKeys = new HashSet<>(); for (K1 key : keys) { uniqueKeys.add(keyEncoder.apply(key)); } return backingMap.getAllPresent(uniqueKeys).thenApply(entries -> ImmutableMap .copyOf(entries.entrySet().stream().collect(Collectors.toMap(o -> keyDecoder.apply(o.getKey()), o -> versionedValueDecoder.apply(o.getValue()))))); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> getOrDefault(K1 key, V1 defaultValue) { try { return backingMap.getOrDefault(keyEncoder.apply(key), valueEncoder.apply(defaultValue)) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> computeIf(K1 key, Predicate<? super V1> condition, BiFunction<? super K1, ? super V1, ? extends V1> remappingFunction) { try { return backingMap .computeIf(keyEncoder.apply(key), v -> condition.test(valueDecoder.apply(v)), (k, v) -> valueEncoder .apply(remappingFunction.apply(keyDecoder.apply(k), valueDecoder.apply(v)))) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> put(K1 key, V1 value, Duration ttl) { try { return backingMap.put(keyEncoder.apply(key), valueEncoder.apply(value), ttl) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> putAndGet(K1 key, V1 value, Duration ttl) { try { return backingMap.putAndGet(keyEncoder.apply(key), valueEncoder.apply(value), ttl) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> remove(K1 key) { try { return backingMap.remove(keyEncoder.apply(key)).thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Void> clear() { return backingMap.clear(); } @Override public AsyncDistributedSet<K1> keySet() { return new TranscodingAsyncDistributedSet<>(backingMap.keySet(), keyEncoder, keyDecoder); } @Override public AsyncDistributedCollection<Versioned<V1>> values() { return new TranscodingAsyncDistributedCollection<>(backingMap.values(), versionedValueEncoder, versionedValueDecoder); } @Override public AsyncDistributedSet<Entry<K1, Versioned<V1>>> entrySet() { return new TranscodingAsyncDistributedSet<>(backingMap.entrySet(), entryEncoder, entryDecoder); } @Override public CompletableFuture<Versioned<V1>> putIfAbsent(K1 key, V1 value, Duration ttl) { try { return backingMap.putIfAbsent(keyEncoder.apply(key), valueEncoder.apply(value), ttl) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Boolean> remove(K1 key, V1 value) { try { return backingMap.remove(keyEncoder.apply(key), valueEncoder.apply(value)); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Boolean> remove(K1 key, long version) { try { return backingMap.remove(keyEncoder.apply(key), version); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Versioned<V1>> replace(K1 key, V1 value) { try { return backingMap.replace(keyEncoder.apply(key), valueEncoder.apply(value)) .thenApply(versionedValueDecoder); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Boolean> replace(K1 key, V1 oldValue, V1 newValue) { try { return backingMap.replace(keyEncoder.apply(key), valueEncoder.apply(oldValue), valueEncoder.apply(newValue)); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Boolean> replace(K1 key, long oldVersion, V1 newValue) { try { return backingMap.replace(keyEncoder.apply(key), oldVersion, valueEncoder.apply(newValue)); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Void> addListener(AtomicMapEventListener<K1, V1> listener, Executor executor) { synchronized (listeners) { InternalBackingAtomicMapEventListener backingMapListener = listeners.computeIfAbsent(listener, k -> new InternalBackingAtomicMapEventListener(listener)); return backingMap.addListener(backingMapListener, executor); } } @Override public CompletableFuture<Void> removeListener(AtomicMapEventListener<K1, V1> listener) { synchronized (listeners) { InternalBackingAtomicMapEventListener backingMapListener = listeners.remove(listener); if (backingMapListener != null) { return backingMap.removeListener(backingMapListener); } else { return CompletableFuture.completedFuture(null); } } } @Override public CompletableFuture<Boolean> prepare(TransactionLog<MapUpdate<K1, V1>> transactionLog) { try { return backingMap.prepare(transactionLog.map(record -> record.map(keyEncoder, valueEncoder))); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Void> commit(TransactionId transactionId) { try { return backingMap.commit(transactionId); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public CompletableFuture<Void> rollback(TransactionId transactionId) { try { return backingMap.rollback(transactionId); } catch (Exception e) { return Futures.exceptionalFuture(e); } } @Override public AtomicMap<K1, V1> sync(Duration operationTimeout) { return new BlockingAtomicMap<>(this, operationTimeout.toMillis()); } private class InternalBackingAtomicMapEventListener implements AtomicMapEventListener<K2, V2> { private final AtomicMapEventListener<K1, V1> listener; InternalBackingAtomicMapEventListener(AtomicMapEventListener<K1, V1> listener) { this.listener = listener; } @Override public void event(AtomicMapEvent<K2, V2> event) { listener.event(new AtomicMapEvent<K1, V1>(event.type(), keyDecoder.apply(event.key()), event.newValue() != null ? event.newValue().map(valueDecoder) : null, event.oldValue() != null ? event.oldValue().map(valueDecoder) : null)); } } }