1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
|
/*
* Copyright (C) 2016 The Android Open Source Project
*
* 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.android.server.wifi.hotspot2;
import com.android.internal.annotations.VisibleForTesting;
import com.android.server.wifi.Clock;
import com.android.server.wifi.hotspot2.anqp.ANQPElement;
import com.android.server.wifi.hotspot2.anqp.Constants;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* Cache for storing ANQP data. This is simply a data cache, all the logic related to
* ANQP data query will be handled elsewhere (e.g. the consumer of the cache).
*/
public class AnqpCache {
@VisibleForTesting
public static final long CACHE_SWEEP_INTERVAL_MILLISECONDS = 60000L;
private long mLastSweep;
private Clock mClock;
private final Map<ANQPNetworkKey, ANQPData> mANQPCache;
public AnqpCache(Clock clock) {
mClock = clock;
mANQPCache = new HashMap<>();
mLastSweep = mClock.getElapsedSinceBootMillis();
}
/**
* Add an ANQP entry associated with the given key.
*
* @param key The key that's associated with the entry
* @param anqpElements The ANQP elements from the AP
*/
public void addEntry(ANQPNetworkKey key,
Map<Constants.ANQPElementType, ANQPElement> anqpElements) {
ANQPData data = new ANQPData(mClock, anqpElements);
mANQPCache.put(key, data);
}
/**
* Get the ANQP data associated with the given AP.
*
* @param key The key that's associated with the entry
* @return {@link ANQPData}
*/
public ANQPData getEntry(ANQPNetworkKey key) {
return mANQPCache.get(key);
}
/**
* Go through the cache to remove any expired entries.
*/
public void sweep() {
long now = mClock.getElapsedSinceBootMillis();
// Check if it is time to perform the sweep.
if (now < mLastSweep + CACHE_SWEEP_INTERVAL_MILLISECONDS) {
return;
}
// Get all expired keys.
List<ANQPNetworkKey> expiredKeys = new ArrayList<>();
for (Map.Entry<ANQPNetworkKey, ANQPData> entry : mANQPCache.entrySet()) {
if (entry.getValue().expired(now)) {
expiredKeys.add(entry.getKey());
}
}
// Remove all expired entries.
for (ANQPNetworkKey key : expiredKeys) {
mANQPCache.remove(key);
}
mLastSweep = now;
}
public void dump(PrintWriter out) {
out.println("Last sweep " + Utils.toHMS(mClock.getElapsedSinceBootMillis() - mLastSweep)
+ " ago.");
for (Map.Entry<ANQPNetworkKey, ANQPData> entry : mANQPCache.entrySet()) {
out.println(entry.getKey() + ": " + entry.getValue());
}
}
}
|
