-
Notifications
You must be signed in to change notification settings - Fork 1.6k
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Introducing AsyncCache, split from AsyncLoadingCache (fixes #246)
- Loading branch information
Showing
22 changed files
with
1,604 additions
and
1,282 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
125 changes: 125 additions & 0 deletions
125
caffeine/src/main/java/com/github/benmanes/caffeine/cache/AsyncCache.java
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,125 @@ | ||
| /* | ||
| * Copyright 2018 Ben Manes. All Rights Reserved. | ||
| * | ||
| * 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 com.github.benmanes.caffeine.cache; | ||
|
|
||
| import java.util.concurrent.CompletableFuture; | ||
| import java.util.concurrent.Executor; | ||
| import java.util.function.BiFunction; | ||
| import java.util.function.Function; | ||
|
|
||
| import javax.annotation.Nonnull; | ||
| import javax.annotation.Nullable; | ||
| import javax.annotation.concurrent.ThreadSafe; | ||
|
|
||
| /** | ||
| * A semi-persistent mapping from keys to values. Cache entries are manually added using | ||
| * {@link #get(Object, Function)} or {@link #put(Object, CompletableFuture)}, and are stored in the | ||
| * cache until either evicted or manually invalidated. | ||
| * <p> | ||
| * Implementations of this interface are expected to be thread-safe, and can be safely accessed by | ||
| * multiple concurrent threads. | ||
| * | ||
| * @author ben.manes@gmail.com (Ben Manes) | ||
| * @param <K> the type of keys maintained by this cache | ||
| * @param <V> the type of mapped values | ||
| */ | ||
| @ThreadSafe | ||
| public interface AsyncCache<K, V> { | ||
|
|
||
| /** | ||
| * Returns the future associated with {@code key} in this cache, or {@code null} if there is no | ||
| * cached future for {@code key}. | ||
| * | ||
| * @param key key whose associated value is to be returned | ||
| * @return the current (existing or computed) future value to which the specified key is mapped, | ||
| * or {@code null} if this map contains no mapping for the key | ||
| * @throws NullPointerException if the specified key is null | ||
| */ | ||
| @Nullable | ||
| CompletableFuture<V> getIfPresent(@Nonnull Object key); | ||
|
|
||
| /** | ||
| * Returns the future associated with {@code key} in this cache, obtaining that value from | ||
| * {@code mappingFunction} if necessary. This method provides a simple substitute for the | ||
| * conventional "if cached, return; otherwise create, cache and return" pattern. | ||
| * <p> | ||
| * If the specified key is not already associated with a value, attempts to compute its value | ||
| * asynchronously and enters it into this cache unless {@code null}. The entire method invocation | ||
| * is performed atomically, so the function is applied at most once per key. If the asynchronous | ||
| * computation fails, the entry will be automatically removed from this cache. | ||
| * <p> | ||
| * <b>Warning:</b> as with {@link CacheLoader#load}, {@code mappingFunction} <b>must not</b> | ||
| * attempt to update any other mappings of this cache. | ||
| * | ||
| * @param key key with which the specified value is to be associated | ||
| * @param mappingFunction the function to asynchronously compute a value | ||
| * @return the current (existing or computed) future value associated with the specified key | ||
| * @throws NullPointerException if the specified key or mappingFunction is null | ||
| */ | ||
| @Nonnull | ||
| CompletableFuture<V> get(@Nonnull K key, | ||
| @Nonnull Function<? super K, ? extends V> mappingFunction); | ||
|
|
||
| /** | ||
| * Returns the future associated with {@code key} in this cache, obtaining that value from | ||
| * {@code mappingFunction} if necessary. This method provides a simple substitute for the | ||
| * conventional "if cached, return; otherwise create, cache and return" pattern. | ||
| * <p> | ||
| * If the specified key is not already associated with a value, attempts to compute its value | ||
| * asynchronously and enters it into this cache unless {@code null}. The entire method invocation | ||
| * is performed atomically, so the function is applied at most once per key. If the asynchronous | ||
| * computation fails, the entry will be automatically removed from this cache. | ||
| * <p> | ||
| * <b>Warning:</b> as with {@link CacheLoader#load}, {@code mappingFunction} <b>must not</b> | ||
| * attempt to update any other mappings of this cache. | ||
| * | ||
| * @param key key with which the specified value is to be associated | ||
| * @param mappingFunction the function to asynchronously compute a value | ||
| * @return the current (existing or computed) future value associated with the specified key | ||
| * @throws NullPointerException if the specified key or mappingFunction is null, or if the | ||
| * future returned by the mappingFunction is null | ||
| * @throws RuntimeException or Error if the mappingFunction does when constructing the future, | ||
| * in which case the mapping is left unestablished | ||
| */ | ||
| @Nonnull | ||
| CompletableFuture<V> get(@Nonnull K key, | ||
| @Nonnull BiFunction<? super K, Executor, CompletableFuture<V>> mappingFunction); | ||
|
|
||
| /** | ||
| * Associates {@code value} with {@code key} in this cache. If the cache previously contained a | ||
| * value associated with {@code key}, the old value is replaced by {@code value}. If the | ||
| * asynchronous computation fails, the entry will be automatically removed. | ||
| * <p> | ||
| * Prefer {@link #get(Object, Function)} when using the conventional "if cached, return; otherwise | ||
| * create, cache and return" pattern. | ||
| * | ||
| * @param key key with which the specified value is to be associated | ||
| * @param valueFuture value to be associated with the specified key | ||
| * @throws NullPointerException if the specified key or value is null | ||
| */ | ||
| void put(@Nonnull K key, @Nonnull CompletableFuture<V> valueFuture); | ||
|
|
||
| /** | ||
| * Returns a view of the entries stored in this cache as a synchronous {@link Cache}. A mapping is | ||
| * not present if the value is currently being loaded. Modifications made to the synchronous cache | ||
| * directly affect the asynchronous cache. If a modification is made to a mapping that is | ||
| * currently loading, the operation blocks until the computation completes. | ||
| * | ||
| * @return a thread-safe synchronous view of this cache | ||
| */ | ||
| @Nonnull | ||
| Cache<K, V> synchronous(); | ||
| } |
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Oops, something went wrong.