1 /*
2 * ====================================================================
3 * Licensed to the Apache Software Foundation (ASF) under one
4 * or more contributor license agreements. See the NOTICE file
5 * distributed with this work for additional information
6 * regarding copyright ownership. The ASF licenses this file
7 * to you under the Apache License, Version 2.0 (the
8 * "License"); you may not use this file except in compliance
9 * with the License. You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing,
14 * software distributed under the License is distributed on an
15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
16 * KIND, either express or implied. See the License for the
17 * specific language governing permissions and limitations
18 * under the License.
19 * ====================================================================
20 *
21 * This software consists of voluntary contributions made by many
22 * individuals on behalf of the Apache Software Foundation. For more
23 * information on the Apache Software Foundation, please see
24 * <http://www.apache.org/>.
25 *
26 */
27 package org.apache.hc.client5.http.cache;
28
29 import java.util.Collection;
30 import java.util.Map;
31
32 import org.apache.hc.core5.annotation.Contract;
33 import org.apache.hc.core5.annotation.ThreadingBehavior;
34
35 /**
36 * {@literal HttpCacheStorage} represents an abstract HTTP cache
37 * storage backend that can then be plugged into the classic
38 * (blocking) request execution pipeline.
39 * <p>
40 * Implementations of this interface are expected to be threading-safe.
41 * </p>
42 *
43 * @since 4.1
44 */
45 @Contract(threading = ThreadingBehavior.SAFE)
46 public interface HttpCacheStorage {
47
48 /**
49 * Store a given cache entry under the given key.
50 * @param key where in the cache to store the entry
51 * @param entry cached response to store
52 * @throws ResourceIOException
53 */
54 void putEntry(String key, HttpCacheEntry entry) throws ResourceIOException;
55
56 /**
57 * Retrieves the cache entry stored under the given key
58 * or null if no entry exists under that key.
59 * @param key cache key
60 * @return an {@link HttpCacheEntry} or {@code null} if no
61 * entry exists
62 * @throws ResourceIOException
63 */
64 HttpCacheEntry getEntry(String key) throws ResourceIOException;
65
66 /**
67 * Deletes/invalidates/removes any cache entries currently
68 * stored under the given key.
69 * @param key
70 * @throws ResourceIOException
71 */
72 void removeEntry(String key) throws ResourceIOException;
73
74 /**
75 * Atomically applies the given callback to processChallenge an existing cache
76 * entry under a given key.
77 * @param key indicates which entry to modify
78 * @param casOperation the CAS operation to perform.
79 * @throws ResourceIOException
80 * @throws HttpCacheUpdateException
81 */
82 void updateEntry(
83 String key, HttpCacheCASOperation casOperation) throws ResourceIOException, HttpCacheUpdateException;
84
85
86 /**
87 * Retrieves multiple cache entries stored under the given keys. Some implementations
88 * may use a single bulk operation to do the retrieval.
89 *
90 * @param keys cache keys
91 * @return an map of {@link HttpCacheEntry}s.
92 *
93 * @since 5.0
94 */
95 Map<String, HttpCacheEntry> getEntries(Collection<String> keys) throws ResourceIOException;
96
97 }