| /* |
| * 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()); |
| } |
| } |
| } |