/*
* Copyright 2017-present Facebook, Inc.
*
* 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.facebook.buck.rules.keys;
import com.facebook.buck.rules.BuildRule;
import com.facebook.buck.rules.RuleKeyAppendable;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import java.util.concurrent.ExecutionException;
import java.util.function.Function;
/**
* A {@link com.facebook.buck.rules.RuleKey} cache used by a {@link RuleKeyFactory}. As items are
* add-only, this is intended to be used in a single build.
*
* @param <V> The rule key type.
*/
public class SingleBuildRuleKeyCache<V> {
// Use key identity when caching.
private final Cache<BuildRule, V> buildRuleCache = CacheBuilder.newBuilder().weakKeys().build();
private final Cache<RuleKeyAppendable, V> ruleKeyAppendableVCache =
CacheBuilder.newBuilder().weakKeys().build();
private <K> V getInternal(Cache<K, V> cache, K key, Function<K, V> create) {
try {
return cache.get(key, () -> create.apply(key));
} catch (ExecutionException e) {
throw new RuntimeException(e);
}
}
public V get(BuildRule rule, Function<BuildRule, V> create) {
return getInternal(buildRuleCache, rule, create);
}
public V get(RuleKeyAppendable appendable, Function<RuleKeyAppendable, V> create) {
return getInternal(ruleKeyAppendableVCache, appendable, create);
}
}