summaryrefslogtreecommitdiffstats
path: root/guava/src/com/google/common/cache/ForwardingCache.java
diff options
context:
space:
mode:
Diffstat (limited to 'guava/src/com/google/common/cache/ForwardingCache.java')
-rw-r--r--guava/src/com/google/common/cache/ForwardingCache.java146
1 files changed, 146 insertions, 0 deletions
diff --git a/guava/src/com/google/common/cache/ForwardingCache.java b/guava/src/com/google/common/cache/ForwardingCache.java
new file mode 100644
index 0000000..44fe683
--- /dev/null
+++ b/guava/src/com/google/common/cache/ForwardingCache.java
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2011 The Guava Authors
+ *
+ * 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.google.common.cache;
+
+import com.google.common.annotations.Beta;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ForwardingObject;
+import com.google.common.collect.ImmutableMap;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentMap;
+import java.util.concurrent.ExecutionException;
+
+import javax.annotation.Nullable;
+
+/**
+ * A cache which forwards all its method calls to another cache. Subclasses should override one or
+ * more methods to modify the behavior of the backing cache as desired per the
+ * <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
+ *
+ * @author Charles Fry
+ * @since 10.0
+ */
+@Beta
+public abstract class ForwardingCache<K, V> extends ForwardingObject implements Cache<K, V> {
+
+ /** Constructor for use by subclasses. */
+ protected ForwardingCache() {}
+
+ @Override
+ protected abstract Cache<K, V> delegate();
+
+ /**
+ * @since 11.0
+ */
+ @Override
+ @Nullable
+ public V getIfPresent(Object key) {
+ return delegate().getIfPresent(key);
+ }
+
+ /**
+ * @since 11.0
+ */
+ @Override
+ public V get(K key, Callable<? extends V> valueLoader) throws ExecutionException {
+ return delegate().get(key, valueLoader);
+ }
+
+ /**
+ * @since 11.0
+ */
+ @Override
+ public ImmutableMap<K, V> getAllPresent(Iterable<?> keys) {
+ return delegate().getAllPresent(keys);
+ }
+
+ /**
+ * @since 11.0
+ */
+ @Override
+ public void put(K key, V value) {
+ delegate().put(key, value);
+ }
+
+ /**
+ * @since 12.0
+ */
+ @Override
+ public void putAll(Map<? extends K,? extends V> m) {
+ delegate().putAll(m);
+ }
+
+ @Override
+ public void invalidate(Object key) {
+ delegate().invalidate(key);
+ }
+
+ /**
+ * @since 11.0
+ */
+ @Override
+ public void invalidateAll(Iterable<?> keys) {
+ delegate().invalidateAll(keys);
+ }
+
+ @Override
+ public void invalidateAll() {
+ delegate().invalidateAll();
+ }
+
+ @Override
+ public long size() {
+ return delegate().size();
+ }
+
+ @Override
+ public CacheStats stats() {
+ return delegate().stats();
+ }
+
+ @Override
+ public ConcurrentMap<K, V> asMap() {
+ return delegate().asMap();
+ }
+
+ @Override
+ public void cleanUp() {
+ delegate().cleanUp();
+ }
+
+ /**
+ * A simplified version of {@link ForwardingCache} where subclasses can pass in an already
+ * constructed {@link Cache} as the delegete.
+ *
+ * @since 10.0
+ */
+ @Beta
+ public abstract static class SimpleForwardingCache<K, V> extends ForwardingCache<K, V> {
+ private final Cache<K, V> delegate;
+
+ protected SimpleForwardingCache(Cache<K, V> delegate) {
+ this.delegate = Preconditions.checkNotNull(delegate);
+ }
+
+ @Override
+ protected final Cache<K, V> delegate() {
+ return delegate;
+ }
+ }
+}