部署的服务器上的Hazelcast抛出java.lang.ClassNotFoundException和本地not

Question

我想将使用Hazelcast3.12.9作为兑现机制的Spring Boot应用程序升级到Java11和Tomcat9。当我在本地部署时，一切看起来都工作得很好，缓存也成功地工作了。但当应用程序在集群上运行时,我从所有可用的3个节点收到以下错误：

com.hazelcast.nio.serialization.HazelcastSerializationException: java.lang.ClassNotFoundException: com.some.service.some.server.domain.ClassA
    at com.hazelcast.internal.serialization.impl.JavaDefaultSerializers$JavaSerializer.read(JavaDefaultSerializers.java:88)
    at com.hazelcast.internal.serialization.impl.JavaDefaultSerializers$JavaSerializer.read(JavaDefaultSerializers.java:77)
    at com.hazelcast.internal.serialization.impl.StreamSerializerAdapter.read(StreamSerializerAdapter.java:48)
    at com.hazelcast.internal.serialization.impl.AbstractSerializationService.toObject(AbstractSerializationService.java:187)
    at com.hazelcast.map.impl.proxy.MapProxySupport.toObject(MapProxySupport.java:1237)
    at com.hazelcast.map.impl.proxy.MapProxyImpl.get(MapProxyImpl.java:120)
    at com.hazelcast.spring.cache.HazelcastCache.lookup(HazelcastCache.java:162)
    at com.hazelcast.spring.cache.HazelcastCache.get(HazelcastCache.java:67)
    at com.some.service.some.server.domain.ClassACache.get(GlassACache.java:28)
    at com.some.service.some.server.domain.ClassAFacade.getClassA(ClassAFacade.java:203)
    at com.some.service.some.server.domain.ClassAFacade.getGlassA(ClassAFacade.java:185)
    at com.some.service.some.server.domain.ClassALogic.lambda$getClassAInParallel$1(ClassALogic.java:196)
    at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
    at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1655)
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
    at java.base/java.util.stream.ReduceOps$ReduceTask.doLeaf(ReduceOps.java:952)
    at java.base/java.util.stream.ReduceOps$ReduceTask.doLeaf(ReduceOps.java:926)
    at java.base/java.util.stream.AbstractTask.compute(AbstractTask.java:327)
    at java.base/java.util.concurrent.CountedCompleter.exec(CountedCompleter.java:746)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:290)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1020)
    at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1656)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1594)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:183)
Caused by: java.lang.ClassNotFoundException: com.some.service.some.server.domain.ClassA
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
    at com.hazelcast.nio.ClassLoaderUtil.tryLoadClass(ClassLoaderUtil.java:288)

Hazelcast自定义程序：

@Configuration
public class ClassAHazelcastConfig {
    private static final MaxSizePolicy HAZELCAST_DEFAULT_MAX_SIZE_POLICY = MaxSizePolicy.PER_NODE;
    private static final EvictionPolicy HAZELCAST_DEFAULT_EVICTION_POLICY = EvictionPolicy.LRU;

    @Bean
    HazelcastConfigurationCustomizer customizer(CachePropertiesHolder cacheProperties) {
        return config -> {
            config.addMapConfig(new MapConfig()
                    .setName(CLASS_A_CACHE)
                    .setMaxSizeConfig(new MaxSizeConfig(cacheProperties.getMaxsize(), HAZELCAST_DEFAULT_MAX_SIZE_POLICY))
                    .setEvictionPolicy(HAZELCAST_DEFAULT_EVICTION_POLICY)
                    .setTimeToLiveSeconds(cacheProperties.getTtl()));

            config.getSerializationConfig().addSerializerConfig(
                    new SerializerConfig()
                            .setImplementation(new OptionalStreamSerializer())
                            .setTypeClass(Optional.class)
            );
        };
    }
}

@Configuration
@EnableConfigurationProperties(CachePropertiesHolder.class)
public class CacheConfig implements CachingConfigurer, EnvironmentAware, ApplicationContextAware {

    public static final String CLASS_A_CACHE = "CACHE_A";

    private Environment environment;
    private ApplicationContext applicationContext;

    @Override
    @Bean(name="cacheManager")
    public CacheManager cacheManager() {
        boolean cachingEnabled = Boolean.parseBoolean(environment.getProperty("cache.enabled"));
        if (cachingEnabled) {
            HazelcastInstance instance = (HazelcastInstance) applicationContext.getBean("hazelcastInstance");
            return new HazelcastCacheManager(instance);
        }
        return new NoOpCacheManager();
    }

    @Override
    public CacheResolver cacheResolver() {
        return new SimpleCacheResolver(Objects.requireNonNull(cacheManager()));
    }

    @Bean
    @Override
    public KeyGenerator keyGenerator() {
        return new SimpleKeyGenerator();
    }

    @Bean
    @Override
    public CacheErrorHandler errorHandler() {
        return new SimpleCacheErrorHandler();
    }

    @Override
    public void setEnvironment(@NotNull Environment environment) {
        this.environment = environment;
    }

    @Override
    public void setApplicationContext(@NotNull ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }
}

经过几天的调查，我看到了将这些异常抛入并行流中的唯一地方。

return forkJoinPool.submit(() ->
                    items.parallelStream()
                            .map(item -> {
                                try {
                                    return biFunction.apply(item);
                                } catch (Exception e) {
                                    LOG.error("Error", e);
                                    return Optional.<Item>empty();
                                }
                            })

奇怪的是，在Java8和Tomcat8中，我没有这个问题。

Answer 1

Hazelcast提供了两种部署模型：嵌入式模式和客户机-服务器模式。更多信息请查看相关文档部分。

在前一种情况下，只有一个JVM，所有类都在类路径上。

在后一种情况下，您至少有2个JVM，一个用于每个客户机，一个用于成员。您似乎忘记了设置成员的类路径以引用classa。

如何设置类路径取决于启动Hazelcast成员的方式。在大多数情况下工作的方法是使用classpath环境变量。