Kafka使用LZ4解压缩从主题读取数据时，会导致lz4-java发生IllegalAccessError错误。

Question

我目前正在处理的项目中，我们有四个基于Spring的应用程序，它们从各种Kafka主题中读写数据。由于发送的数据量很大，所以我们决定启用LZ4压缩。这对三个应用程序完全没有问题，但对第四个应用程序造成了巨大的问题。

流程如下：应用程序A接收HTTP请求并将有效负载转换为Kafka消息。应用程序B从应用程序A读取消息，对其进行一些处理，并将其发送到两个不同的主题以供应用程序C和D使用。我们通过将压缩类型配置设置为lz4在A和B的生产者上启用了压缩。然后，我们进行了测试，消息从A到B以及从B到D都可以正常工作。然而，当应用程序C接收到压缩消息时，以下错误开始被不断地记录：

java.lang.IllegalAccessError: failed to access class net.jpountz.lz4.LZ4SafeUtils (class loader System@7452) from class net.jpountz.lz4.LZ4JavaSafeSafeDecompressor (class loader org.springframework.boot.loader.LaunchedURLClassLoader@11104)

我对类加载器不太熟悉，但据我所知，虽然它们属于同一包，但似乎由不同的类加载器加载，导致访问错误？

正在使用的 spring-kafka 版本为 2.7.3，lz4-java 版本为 1.7.1，作为 spring-kafka 的依赖项导入。

我不明白为什么这个问题只在其中一个应用程序上发生，而其他应用程序却没有。因为所有配置都相同（通过一个被所有四个应用程序使用来创建所需 bean 的公共库进行共享和加载）。最初，在出现此问题的应用程序中，我们还导入了另一个库，该库使用了修改过的 lz4-java 版本，因此我们认为问题是从那里引起的。但是，即使完全删除它，仍会收到上述相同的错误。

有人遇到过类似的问题或者可以给我提示，下一步该怎么做来解决这个问题吗？

谢谢。

编辑：应用程序正在云中运行，这是在应用程序日志中看到的堆栈跟踪。以下块一直重复发送，直到关闭或从正在监听的主题中删除压缩的消息为止。

[container-1-C-1] essageListenerContainer$ListenerConsumer : Consumer exception
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT org.springframework.kafka.KafkaException: Seek to current after exception; nested exception is org.apache.kafka.common.KafkaException: Received exception when fetching the next record from ETD-NewUserContextSystemData.ibsoetdcfsubacc4.eb419dde-795b-48a2-977a-8117ac15cb4e-2. If needed, please seek past the record to continue consumption.
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.SeekToCurrentBatchErrorHandler.handle(SeekToCurrentBatchErrorHandler.java:79) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.RecoveringBatchErrorHandler.handle(RecoveringBatchErrorHandler.java:124) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.handleConsumerException(KafkaMessageListenerContainer.java:1603) [spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1210) [spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [?:1.8.0_301]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at java.util.concurrent.FutureTask.run(FutureTask.java:266) [?:1.8.0_301]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at java.lang.Thread.run(Thread.java:836) [?:1.8.0_301]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT Caused by: org.apache.kafka.common.KafkaException: Received exception when fetching the next record from ETD-NewUserContextSystemData.ibsoetdcfsubacc4.eb419dde-795b-48a2-977a-8117ac15cb4e-2. If needed, please seek past the record to continue consumption.
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.fetchRecords(Fetcher.java:1611) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.access$1700(Fetcher.java:1432) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchRecords(Fetcher.java:684) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchedRecords(Fetcher.java:635) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.pollForFetches(KafkaConsumer.java:1303) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1237) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1210) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.doPoll(KafkaMessageListenerContainer.java:1410) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.pollAndInvoke(KafkaMessageListenerContainer.java:1249) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1161) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     ... 3 more
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT Caused by: org.apache.kafka.common.KafkaException: java.lang.IllegalAccessError: failed to access class net.jpountz.lz4.LZ4SafeUtils (class loader System@7452) from class net.jpountz.lz4.LZ4JavaSafeSafeDecompressor (class loader org.springframework.boot.loader.LaunchedURLClassLoader@11104)
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.CompressionType$4.wrapForInput(CompressionType.java:113) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.DefaultRecordBatch.compressedIterator(DefaultRecordBatch.java:261) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.DefaultRecordBatch.streamingIterator(DefaultRecordBatch.java:346) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.nextFetchedRecord(Fetcher.java:1554) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.fetchRecords(Fetcher.java:1591) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.access$1700(Fetcher.java:1432) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchRecords(Fetcher.java:684) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchedRecords(Fetcher.java:635) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.pollForFetches(KafkaConsumer.java:1303) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1237) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1210) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.doPoll(KafkaMessageListenerContainer.java:1410) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.pollAndInvoke(KafkaMessageListenerContainer.java:1249) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1161) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     ... 3 more
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT Caused by: java.lang.IllegalAccessError: failed to access class net.jpountz.lz4.LZ4SafeUtils (class loader System@7452) from class net.jpountz.lz4.LZ4JavaSafeSafeDecompressor (class loader org.springframework.boot.loader.LaunchedURLClassLoader@11104)
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4JavaSafeSafeDecompressor.decompress(LZ4JavaSafeSafeDecompressor.java:71) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4SafeDecompressor.decompress(LZ4SafeDecompressor.java:74) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4Factory.<init>(LZ4Factory.java:214) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4Factory.instance(LZ4Factory.java:51) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4Factory.safeInstance(LZ4Factory.java:105) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4Factory.fastestJavaInstance(LZ4Factory.java:141) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at net.jpountz.lz4.LZ4Factory.fastestInstance(LZ4Factory.java:169) ~[lz4-java-1.7.1.jar:2.9.16-38a800d98fb18a51ecde14f570bbf28d81b66bbc]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.KafkaLZ4BlockInputStream.<clinit>(KafkaLZ4BlockInputStream.java:50) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.CompressionType$4.wrapForInput(CompressionType.java:110) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.DefaultRecordBatch.compressedIterator(DefaultRecordBatch.java:261) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.common.record.DefaultRecordBatch.streamingIterator(DefaultRecordBatch.java:346) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.nextFetchedRecord(Fetcher.java:1554) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.fetchRecords(Fetcher.java:1591) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher$CompletedFetch.access$1700(Fetcher.java:1432) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchRecords(Fetcher.java:684) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.internals.Fetcher.fetchedRecords(Fetcher.java:635) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.pollForFetches(KafkaConsumer.java:1303) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1237) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.apache.kafka.clients.consumer.KafkaConsumer.poll(KafkaConsumer.java:1210) ~[kafka-clients-2.6.2.jar:?]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.doPoll(KafkaMessageListenerContainer.java:1410) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.pollAndInvoke(KafkaMessageListenerContainer.java:1249) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.run(KafkaMessageListenerContainer.java:1161) ~[spring-kafka-2.7.3.jar:2.7.3]
   2021-09-24T10:42:29.30+0300 [APP/PROC/WEB/1] OUT     ... 3 more

- Remus

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请展示完整的堆栈跟踪；对于这样的问题总是需要的。(编辑问题)。 - Gary Russell

Answer 1

我和你一样遇到了同样的问题。在Linux系统运行程序时，我也遇到了这个问题。问题的根本原因可能是：你的Linux操作系统内核不支持从.so文件进行方法调用（如果你使用的是Linux或IBM AIX则不能确定）。.so文件会根据操作系统内核版本，在lz4 jar文件加载到类路径中时自动加载。

你可以运行命令行“uname -a”或“uname -mrs”来检查操作系统内核版本。

如果你打开lz4 jar文件，你会看到“util”包下面有每个操作系统的.so文件。我的想法是，你（以及我）的操作系统内核没有被添加到该库的支持列表中。我们可能需要检查该库的Jira问题列表，看他们是否确认这是一个问题，他们会修复它。

- Linh Vu Tran Nguyen