yang/yang-repo-spi/src/main/java/org/opendaylight/yangtools/yang/model/repo/spi/GuavaSchemaSourceCache.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.yangtools.yang.model.repo.spi;
   9
  10 import com.google.common.annotations.Beta;
  11 import com.google.common.base.FinalizablePhantomReference;
  12 import com.google.common.base.FinalizableReferenceQueue;
  13 import com.google.common.cache.Cache;
  14 import com.google.common.cache.CacheBuilder;
  15 import com.google.common.util.concurrent.FluentFuture;
  16 import java.time.Duration;
  17 import java.util.ArrayList;
  18 import java.util.Collections;
  19 import java.util.List;
  20 import java.util.concurrent.TimeUnit;
  21 import org.eclipse.jdt.annotation.NonNull;
  22 import org.opendaylight.yangtools.util.concurrent.FluentFutures;
  23 import org.opendaylight.yangtools.yang.model.repo.api.MissingSchemaSourceException;
  24 import org.opendaylight.yangtools.yang.model.repo.api.SchemaSourceRepresentation;
  25 import org.opendaylight.yangtools.yang.model.repo.api.SourceIdentifier;
  26
  27 /**
  28  * A simple {@link AbstractSchemaSourceCache} based on {@link Cache Guava Cache}.
  29  *
  30  * @param <T> {@link SchemaSourceRepresentation} type stored in this cache
  31  */
  32 @Beta
  33 public final class GuavaSchemaSourceCache<T extends SchemaSourceRepresentation> extends AbstractSchemaSourceCache<T>
  34         implements AutoCloseable {
  35     // FIXME: 7.0.0: use a java.util.Cleaner?
  36     private final List<FinalizablePhantomReference<T>> regs = Collections.synchronizedList(new ArrayList<>());
  37     private final FinalizableReferenceQueue queue = new FinalizableReferenceQueue();
  38     private final Cache<SourceIdentifier, T> cache;
  39
  40     private GuavaSchemaSourceCache(final SchemaSourceRegistry consumer, final Class<T> representation,
  41             final CacheBuilder<Object, Object> cacheBuilder) {
  42         super(consumer, representation, PotentialSchemaSource.Costs.IMMEDIATE);
  43         cache = cacheBuilder.build();
  44     }
  45
  46     public static <R extends SchemaSourceRepresentation> @NonNull GuavaSchemaSourceCache<R> createSoftCache(
  47             final SchemaSourceRegistry consumer, final Class<R> representation) {
  48         return new GuavaSchemaSourceCache<>(consumer, representation, CacheBuilder.newBuilder().softValues());
  49     }
  50
  51     public static <R extends SchemaSourceRepresentation> @NonNull GuavaSchemaSourceCache<R> createSoftCache(
  52             final SchemaSourceRegistry consumer, final Class<R> representation, final long lifetime,
  53             final TimeUnit units) {
  54         return new GuavaSchemaSourceCache<>(consumer, representation, CacheBuilder.newBuilder().softValues()
  55             .expireAfterAccess(lifetime, units));
  56     }
  57
  58     public static <R extends SchemaSourceRepresentation> @NonNull GuavaSchemaSourceCache<R> createSoftCache(
  59             final SchemaSourceRegistry consumer, final Class<R> representation, final Duration duration) {
  60         return new GuavaSchemaSourceCache<>(consumer, representation, CacheBuilder.newBuilder().softValues()
  61             .expireAfterAccess(duration));
  62     }
  63
  64     @Override
  65     public FluentFuture<? extends T> getSource(final SourceIdentifier sourceIdentifier) {
  66         final T present = cache.getIfPresent(sourceIdentifier);
  67         return present != null ? FluentFutures.immediateFluentFuture(present)
  68                 : FluentFutures.immediateFailedFluentFuture(new MissingSchemaSourceException("Source not found",
  69                     sourceIdentifier));
  70     }
  71
  72     @Override
  73     protected void offer(final T source) {
  74         final T present = cache.getIfPresent(source.getIdentifier());
  75         if (present == null) {
  76             cache.put(source.getIdentifier(), source);
  77
  78             final SchemaSourceRegistration<T> reg = register(source.getIdentifier());
  79             final FinalizablePhantomReference<T> ref = new FinalizablePhantomReference<>(source, queue) {
  80                 @Override
  81                 public void finalizeReferent() {
  82                     reg.close();
  83                     regs.remove(this);
  84                 }
  85             };
  86
  87             regs.add(ref);
  88         }
  89     }
  90
  91     @Override
  92     public void close() {
  93         while (!regs.isEmpty()) {
  94             final FinalizablePhantomReference<?> ref = regs.get(0);
  95             ref.finalizeReferent();
  96         }
  97
  98         cache.invalidateAll();
  99         queue.close();
 100     }
 101 }