auth/auth-core/src/main/java/org/onap/aaf/auth/cache/Cache.java

   1 /**
   2  * ============LICENSE_START====================================================
   3  * org.onap.aaf
   4  * ===========================================================================
   5  * Copyright (c) 2018 AT&T Intellectual Property. All rights reserved.
   6  * ===========================================================================
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * 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, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  * ============LICENSE_END====================================================
  19  *
  20  */
  21
  22 package org.onap.aaf.auth.cache;
  23
  24 import java.util.ArrayList;
  25 import java.util.Date;
  26 import java.util.HashMap;
  27 import java.util.HashSet;
  28 import java.util.List;
  29 import java.util.Map;
  30 import java.util.Set;
  31 import java.util.Timer;
  32 import java.util.TimerTask;
  33 import java.util.concurrent.ConcurrentHashMap;
  34 import java.util.logging.Level;
  35
  36 import org.onap.aaf.misc.env.Env;
  37 import org.onap.aaf.misc.env.Trans;
  38
  39 /**
  40  * Create and maintain a Map of Maps used for Caching
  41  *
  42  * @author Jonathan
  43  *
  44  * @param <TRANS>
  45  * @param <DATA>
  46  */
  47 public class Cache<TRANS extends Trans, DATA> {
  48         private static Clean clean;
  49         private static Timer cleanseTimer;
  50
  51         public static final String CACHE_HIGH_COUNT = "CACHE_HIGH_COUNT";
  52         public static final String CACHE_CLEAN_INTERVAL = "CACHE_CLEAN_INTERVAL";
  53
  54         private static final Map<String,Map<String,Dated>> cacheMap;
  55
  56         static {
  57                 cacheMap = new HashMap<>();
  58         }
  59
  60         /**
  61          * Dated Class - store any Data with timestamp
  62          *
  63          * @author Jonathan
  64          *
  65          */
  66         public static final class Dated {
  67                 public Date timestamp;
  68                 public List<?> data;
  69                 private long expireIn;
  70
  71                 public Dated(List<?> data, long expireIn) {
  72                         timestamp = new Date(System.currentTimeMillis()+expireIn);
  73                         this.data = data;
  74                         this.expireIn = expireIn;
  75                 }
  76
  77                 public <T> Dated(T t, long expireIn) {
  78                         timestamp = new Date(System.currentTimeMillis()+expireIn);
  79                         ArrayList<T> al = new ArrayList<>(1);
  80                         al.add(t);
  81                         data = al;
  82                         this.expireIn = expireIn;
  83                 }
  84
  85                 public void touch() {
  86                         timestamp = new Date(System.currentTimeMillis()+expireIn);
  87                 }
  88         }
  89
  90         public static Map<String,Dated> obtain(String key) {
  91                 Map<String, Dated> m = cacheMap.get(key);
  92                 if(m==null) {
  93                         m = new ConcurrentHashMap<>();
  94                         synchronized(cacheMap) {
  95                                 cacheMap.put(key, m);
  96                         }
  97                 }
  98                 return m;
  99         }
 100
 101         /**
 102          * Clean will examine resources, and remove those that have expired.
 103          *
 104          * If "highs" have been exceeded, then we'll expire 10% more the next time.  This will adjust after each run
 105          * without checking contents more than once, making a good average "high" in the minimum speed.
 106          *
 107          * @author Jonathan
 108          *
 109          */
 110         private static final class Clean extends TimerTask {
 111                 private final Env env;
 112                 private Set<String> set;
 113
 114                 // The idea here is to not be too restrictive on a high, but to Expire more items by
 115                 // shortening the time to expire.  This is done by judiciously incrementing "advance"
 116                 // when the "highs" are exceeded.  This effectively reduces numbers of cached items quickly.
 117                 private final int high;
 118                 private long advance;
 119                 private final long timeInterval;
 120
 121                 public Clean(Env env, long cleanInterval, int highCount) {
 122                         this.env = env;
 123                         high = highCount;
 124                         timeInterval = cleanInterval;
 125                         advance = 0;
 126                         set = new HashSet<>();
 127                 }
 128
 129                 public synchronized void add(String key) {
 130                         set.add(key);
 131                 }
 132
 133                 public void run() {
 134                         int count = 0;
 135                         int total = 0;
 136                         // look at now.  If we need to expire more by increasing "now" by "advance"
 137                         Date now = new Date(System.currentTimeMillis() + advance);
 138
 139
 140                         for(String name : set) {
 141                                 Map<String,Dated> map = cacheMap.get(name);
 142                                 if(map==null) {
 143                                         continue;
 144                                 }
 145
 146                                 for(Map.Entry<String,Dated> me : map.entrySet()) {
 147                                         ++total;
 148                                         if (me.getValue().timestamp.before(now)) {
 149                                                 map.remove(me.getKey());
 150                                                 ++count;
 151                                         }
 152                                 }
 153                         }
 154
 155                         if(count>0) {
 156                                 env.info().log(Level.INFO, "Cache removed",count,"expired Cached Elements out of", total);
 157                         }
 158
 159                         // If High (total) is reached during this period, increase the number of expired services removed for next time.
 160                         // There's no point doing it again here, as there should have been cleaned items.
 161                         if(total>high) {
 162                                 // advance cleanup by 10%, without getting greater than timeInterval.
 163                                 advance = Math.min(timeInterval, advance+(timeInterval/10));
 164                         } else {
 165                                 // reduce advance by 10%, without getting lower than 0.
 166                                 advance = Math.max(0, advance-(timeInterval/10));
 167                         }
 168                 }
 169         }
 170
 171         public static synchronized void startCleansing(Env env, String ... keys) {
 172                 if(cleanseTimer==null) {
 173                         cleanseTimer = new Timer("Cache Cleanup Timer");
 174                         int cleanInterval = Integer.parseInt(env.getProperty(CACHE_CLEAN_INTERVAL,"60000")); // 1 minute clean cycles
 175                         int highCount = Integer.parseInt(env.getProperty(CACHE_HIGH_COUNT,"5000"));
 176                         cleanseTimer.schedule(clean = new Clean(env, cleanInterval, highCount), cleanInterval, cleanInterval);
 177                 }
 178
 179                 for(String key : keys) {
 180                         clean.add(key);
 181                 }
 182         }
 183
 184         public static void stopTimer() {
 185                 if(cleanseTimer!=null) {
 186                         cleanseTimer.cancel();
 187                         cleanseTimer = null;
 188                 }
 189         }
 190
 191         public static void addShutdownHook() {
 192                 Runtime.getRuntime().addShutdownHook(new Thread() {
 193                         @Override
 194                         public void run() {
 195                                 Cache.stopTimer();
 196                         }
 197                 });
 198         }
 199
 200 }