slfan1989 commented on code in PR #5897: URL: https://github.com/apache/hadoop/pull/5897#discussion_r1280115270
########## hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/delegation/DelegationTokenLoadingCache.java: ########## @@ -0,0 +1,116 @@ +/** + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you 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 org.apache.hadoop.security.token.delegation; + +import java.util.Collection; +import java.util.Map; +import java.util.Set; +import java.util.concurrent.TimeUnit; +import java.util.function.Function; +import org.apache.hadoop.thirdparty.com.google.common.cache.CacheBuilder; +import org.apache.hadoop.thirdparty.com.google.common.cache.CacheLoader; +import org.apache.hadoop.thirdparty.com.google.common.cache.LoadingCache; + + +/** + * Cache for delegation tokens that can handle high volume of tokens. A + * loading cache will prevent all active tokens from being in memory at the + * same time. It will also trigger more requests from the persistent token storage. + */ +public class DelegationTokenLoadingCache<K, V> implements Map<K, V> { + private LoadingCache<K, V> internalLoadingCache; + + public DelegationTokenLoadingCache(long cacheExpirationMs, Function<K, V> singleEntryFunction) { + this.internalLoadingCache = CacheBuilder.newBuilder() + .expireAfterWrite(cacheExpirationMs, TimeUnit.MILLISECONDS) Review Comment: Do we need to increase the limit of a number? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: common-issues-h...@hadoop.apache.org
