Java Cache類代碼示例

import com.google.common.cache.Cache; //導入依賴的package包/類
private Cache<Object, Object> createInMemoryCache(String cacheId, String cacheName) {
    Cache<Object, Object> inMemoryCache = this.cache.getIfPresent(cacheId);
    if (inMemoryCache != null) {
        LOG.info("In-memory cache of {}: Size{{}}, {}", cacheId, inMemoryCache.size(), inMemoryCache.stats());
    } else {
        Integer maxSize = cacheCapSizer.getMaxSize(cacheName);
        assert maxSize != null : "Unknown cache.";
        LOG.debug("Creating In-memory cache of {}: MaxSize{{}}", cacheId, maxSize);
        LoggingEvictionListener evictionListener = new LoggingEvictionListener(cacheId, maxSize);
        final CacheBuilder<Object, Object> cacheBuilder = CacheBuilder.newBuilder().maximumSize(maxSize).recordStats().removalListener(evictionListener);
        inMemoryCache = cacheBuilder.build();
        evictionListener.setCache(inMemoryCache);
        this.cache.put(cacheId, inMemoryCache);
    }
    return inMemoryCache;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
/**
 * Create a ChronoRange for the given ChronoSeries and sequence of ChronoGenes.
 *
 * @param chronoSeries ChronoSeries to create ChronoRange for
 * @param genes ChronoGene sequence containing ChronoPattern(s) to use for creating ChronoRange
 * @return ChronoRange for given ChronoSeries and ChronoGene sequence
 */
@NotNull
public static ChronoRange getChronoRange(@NotNull ChronoSeries chronoSeries, @NotNull ISeq<ChronoGene> genes) {
    ChronoRange range = new ChronoRange(requireNonNull(chronoSeries), requireNonNull(genes));
    Cache<ISeq<ChronoPattern>, ChronoRange> cacheChronoRange = cacheMap.get(chronoSeries);
    if (cacheChronoRange == null) {
        cacheChronoRange = CacheBuilder.newBuilder().build();
        cacheMap.put(chronoSeries, cacheChronoRange);
    }

    ChronoRange cacheRange = cacheChronoRange.getIfPresent(range.chronoPatternSeq);
    if (cacheRange != null) {
        return cacheRange;
    } else {
        if (range.validRange) {
            range.calculateTimestampRanges();
        }

        cacheChronoRange.put(range.chronoPatternSeq, range);
        return range;
    }
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
public HandlerToPreparePlan(
    QueryContext context,
    SqlNode sqlNode,
    SqlToPlanHandler handler,
    Cache<Long, PreparedPlan> planCache,
    String sql,
    AttemptObserver observer,
    SqlHandlerConfig config) {
  this.context = context;
  this.sqlNode = sqlNode;
  this.handler = handler;
  this.planCache = planCache;
  this.sql = sql;
  this.observer = observer;
  this.config = config;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Override public Cache<Integer, Object>
getRemoteStatementMap(AvaticaConnection connection) throws Exception {
  Field metaF = AvaticaConnection.class.getDeclaredField("meta");
  metaF.setAccessible(true);
  Meta clientMeta = (Meta) metaF.get(connection);
  Field remoteMetaServiceF = clientMeta.getClass().getDeclaredField("service");
  remoteMetaServiceF.setAccessible(true);
  LocalProtobufService remoteMetaService =
      (LocalProtobufService) remoteMetaServiceF.get(clientMeta);
  // Use the explicitly class to avoid issues with LoggingLocalJsonService
  Field remoteMetaServiceServiceF = LocalProtobufService.class.getDeclaredField("service");
  remoteMetaServiceServiceF.setAccessible(true);
  LocalService remoteMetaServiceService =
      (LocalService) remoteMetaServiceServiceF.get(remoteMetaService);
  Field remoteMetaServiceServiceMetaF =
      remoteMetaServiceService.getClass().getDeclaredField("meta");
  remoteMetaServiceServiceMetaF.setAccessible(true);
  JdbcMeta serverMeta = (JdbcMeta) remoteMetaServiceServiceMetaF.get(remoteMetaServiceService);
  Field jdbcMetaStatementMapF = JdbcMeta.class.getDeclaredField("statementCache");
  jdbcMetaStatementMapF.setAccessible(true);
  //noinspection unchecked
  @SuppressWarnings("unchecked")
  Cache<Integer, Object> cache = (Cache<Integer, Object>) jdbcMetaStatementMapF.get(serverMeta);
  return cache;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
public void schemaCacheItemsGetAddedUponInstanceAccess() {
    // Initially there should be no entries on the schemaDescriptionIdCache
    Cache<SchemaKey, Set<SchemaKey>> schemaDescriptionIdCache = cacheService.getSchemaDescriptionIdCache();
    assertEquals(schemaDescriptionIdCache.size(), 0);

    // Creating auxiliary objects prior to execute queries
    Map<String, Object> variableMap = buildVariableMap(CACHE_TEST_NAMESPACE, MEDIA_DOMAIN_NAME);

    SchemaWriteAccess access = buildSchemaWriteAccessCacheTestNamespace();

    // Run a query on media that should populate the reference cache for it
    GraphQLResult addMediaInstanceResult = instanceService.executeQuery(addMediaInstance, variableMap, access, DEFAULT_MAX_RECURSE_DEPTH);
    assertTrue(addMediaInstanceResult.isSuccessful());

    // Lookup for "Media" referenced types
    Set<SchemaKey> schemaKeySets = schemaDescriptionIdCache.getIfPresent(new SchemaKey(MEDIA_DOMAIN_NAME, SCHEMA_NAME_SPACE));

    // Media should have 2 referenced types (Video and Audio)
    assertNotNull(schemaKeySets);
    assertEquals(schemaKeySets.size(), 2);

    assertTrue(schemaKeySets.contains(new SchemaKey(VIDEO_DOMAIN_NAME, SCHEMA_NAME_SPACE)));
    assertTrue(schemaKeySets.contains(new SchemaKey(AUDIO_DOMAIN_NAME, SCHEMA_NAME_SPACE)));
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Override
public OAuthUserState getUserState(String tokenData, HttpServletRequest request)
{
	Cache<String, OAuthUserState> userCache = getUserCache(CurrentInstitution.get());
	OAuthUserState oauthUserState = userCache.getIfPresent(tokenData);
	if( oauthUserState == null )
	{
		// find the token and the user associated with it
		final OAuthToken token = oauthService.getToken(tokenData);
		if( token == null )
		{
			// FIXME: Need to fall back on server language since
			// LocaleEncodingFilter has not run yet...
			throw new OAuthException(403, OAuthConstants.ERROR_ACCESS_DENIED, languageService
				.getResourceBundle(Locale.getDefault(), "resource-centre").getString(KEY_TOKEN_NOT_FOUND));
		}

		final UserState userState = userService.authenticateAsUser(token.getUsername(),
			userService.getWebAuthenticationDetails(request));

		oauthUserState = new OAuthUserStateImpl(userState, token);
		userCache.put(tokenData, oauthUserState);
	}
	return (OAuthUserState) oauthUserState.clone();
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
private <T> T getValueAndStoreToCache(String key, Function<String, T> parser, Cache<String, T> cache, T defaultValue) {
  long currentConfigVersion = m_configVersion.get();
  String value = getProperty(key, null);

  if (value != null) {
    T result = parser.apply(value);

    if (result != null) {
      synchronized (this) {
        if (m_configVersion.get() == currentConfigVersion) {
          cache.put(key, result);
        }
      }
      return result;
    }
  }

  return defaultValue;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
protected Foreman(
        final SabotContext context,
        final Executor executor,
        final CompletionListener listener,
        final ExternalId externalId,
        final QueryObserver observer,
        final UserSession session,
        final UserRequest request,
        final OptionProvider config,
        final ReAttemptHandler attemptHandler,
        final CoordToExecTunnelCreator tunnelCreator,
        Cache<Long, PreparedPlan> plans) {
  this.attemptId = AttemptId.of(externalId);
  this.executor = executor;
  this.context = context;
  this.listener = listener;
  this.session = session;
  this.request = request;
  this.config = config;
  this.observer = observer;
  this.attemptHandler = attemptHandler;
  this.tunnelCreator = tunnelCreator;
  this.plans = plans;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Override public Cache<String, Connection>
getRemoteConnectionMap(AvaticaConnection connection) throws Exception {
  Field metaF = AvaticaConnection.class.getDeclaredField("meta");
  metaF.setAccessible(true);
  Meta clientMeta = (Meta) metaF.get(connection);
  Field remoteMetaServiceF = clientMeta.getClass().getDeclaredField("service");
  remoteMetaServiceF.setAccessible(true);
  LocalProtobufService remoteMetaService =
      (LocalProtobufService) remoteMetaServiceF.get(clientMeta);
  // Get the field explicitly off the correct class to avoid LocalLoggingJsonService.class
  Field remoteMetaServiceServiceF = LocalProtobufService.class.getDeclaredField("service");
  remoteMetaServiceServiceF.setAccessible(true);
  LocalService remoteMetaServiceService =
      (LocalService) remoteMetaServiceServiceF.get(remoteMetaService);
  Field remoteMetaServiceServiceMetaF =
      remoteMetaServiceService.getClass().getDeclaredField("meta");
  remoteMetaServiceServiceMetaF.setAccessible(true);
  JdbcMeta serverMeta = (JdbcMeta) remoteMetaServiceServiceMetaF.get(remoteMetaServiceService);
  Field jdbcMetaConnectionCacheF = JdbcMeta.class.getDeclaredField("connectionCache");
  jdbcMetaConnectionCacheF.setAccessible(true);
  //noinspection unchecked
  @SuppressWarnings("unchecked")
  Cache<String, Connection> cache =
      (Cache<String, Connection>) jdbcMetaConnectionCacheF.get(serverMeta);
  return cache;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
public static Chunk fetchDormantChunk(long coords, World world)
{
    if (dormantChunkCacheSize == 0) return null; // Don't bother with maps at all if its never gonna get a response
    Cache<Long, Chunk> cache = dormantChunkCache.get(world);
    if (cache == null)
    {
        return null;
    }
    Chunk chunk = cache.getIfPresent(coords);
    if (chunk != null)
    {
        for (ClassInheritanceMultiMap<Entity> eList : chunk.getEntityLists())
        {
            Iterator<Entity> itr = eList.iterator();
            while (itr.hasNext())
            {
                (itr.next()).resetEntityId();
            }
        }
    }
    return chunk;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Test public void testStatementLifecycle() throws Exception {
  ConnectionSpec.getDatabaseLock().lock();
  try (AvaticaConnection connection = (AvaticaConnection) getLocalConnection()) {
    Map<Integer, AvaticaStatement> clientMap = connection.statementMap;
    Cache<Integer, Object> serverMap = getLocalConnectionInternals()
        .getRemoteStatementMap(connection);
    // Other tests being run might leave statements in the cache.
    // The lock guards against more statements being cached during the test.
    serverMap.invalidateAll();
    assertEquals(0, clientMap.size());
    assertEquals(0, serverMap.size());
    Statement stmt = connection.createStatement();
    assertEquals(1, clientMap.size());
    assertEquals(1, serverMap.size());
    stmt.close();
    assertEquals(0, clientMap.size());
    assertEquals(0, serverMap.size());
  } finally {
    ConnectionSpec.getDatabaseLock().unlock();
  }
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Override
public void onRemoval(RemovalNotification<Object, Cache<Query, Value>> notification) {
    Object key = notification.getKey();
    if (key == null) {
        return;
    }

    Cache<Query, Value> valueCache = notification.getValue();
    if (valueCache == null) {
        return;
    }

    for (Value value : valueCache.asMap().values()) {
        listener.onRemoval(value.shardId, value.bitset);
        // if null then this means the shard has already been removed and the stats are 0 anyway for the shard this key belongs to
    }
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
@Test
public void guavaCache() throws InterruptedException {

    TesTicker ticker = new TesTicker();
    Cache<String, Pojo> collection = CacheBuilder.newBuilder().expireAfterAccess(5, TimeUnit.SECONDS).ticker(ticker)
            .<String, Pojo> build();
    Pojo p1 = new Pojo("p1name", "p1val");
    Pojo p2 = new Pojo("p2name", "p2val");
    collection.put("p1", p1);
    collection.put("p2", p2);
    ticker.advance(3, TimeUnit.SECONDS);
    Map<String, Pojo> map = collection.asMap();
    assertTrue(map.containsKey("p1"));
    // map.get("p1");
    ticker.advance(3, TimeUnit.SECONDS);
    assertEquals(2, collection.size());
    assertFalse(map.containsKey("p1"));// 有清除過期操作
    assertEquals(1, collection.size());
    assertNull(collection.getIfPresent("p2"));
    assertNull(collection.getIfPresent("p1"));// 有清除過期操作
    assertEquals(0, collection.size());
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
public CommandCreator(
    SabotContext dbContext,
    QueryContext context,
    CoordToExecTunnelCreator tunnelCreator,
    UserRequest request,
    AttemptObserver observer,
    Cache<Long, PreparedPlan> plans,
    Pointer<QueryId> prepareId,
    int attemptNumber) {
  this.context = context;
  this.tunnelCreator = tunnelCreator;
  this.request = request;
  this.observer = observer;
  this.dbContext = dbContext;
  this.plans = plans;
  this.prepareId = prepareId;
  this.attemptNumber = attemptNumber;
}
 

import com.google.common.cache.Cache; //導入依賴的package包/類
private Schema<?> get(final Class<?> cls, Cache<Class<?>, Schema<?>> cache) {
    try {
        return cache.get(cls, () -> RuntimeSchema.createFrom(cls));
    } catch (ExecutionException e) {
        return null;
    }
}