AKS容器出现ClassNotFoundException：ProxyBuilderImpl（UAT异常，测试环境正常）

问题详情 #

• 异常出现在Azure Kubernetes Service（AKS）集群的UAT环境，测试环境（另一AKS集群）无此问题
• 服务已容器化，镜像在测试环境构建后复制到UAT部署
• 具体异常：java.lang.ClassNotFoundException: org.jboss.resteasy.client.jaxrs.internal.proxy.ProxyBuilderImpl

已完成排查 #

• 依赖：Docker镜像已包含Resteasy相关依赖，本地拉取镜像验证时，容器内的resteasy-client-4.7.9.Final.jar中确实存在目标类
• 环境变量：UAT环境必要配置项正确
• 配置文件：测试与UAT环境无明显差异
• 类路径：Docker镜像的类路径配置无误

错误日志 #

java.lang.RuntimeException: Exception while adding Patients to batch 
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.CxxxxxxxxServiceImpl.savePatients(CxxxxxxxxServiceImpl.java:235)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.ExxxxServiceImpl.saveEvents(ExxxxServiceImpl.java:120)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.ExxxxServiceImpl.segregateEventsByEntitiesAndSave(ExxxxServiceImpl.java:184)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.ExxxxServiceImpl.lambda$saveEventsAsEntities$0(ExxxxServiceImpl.java:97)
    at java.base/java.util.concurrent.CompletableFuture$AsyncRun.run(CompletableFuture.java:1804)
    at java.base/java.util.concurrent.CompletableFuture$AsyncRun.exec(CompletableFuture.java:1796)
    at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:373)
    at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1182)
    at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1655)
    at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1622)
    at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:165)
Caused by: java.lang.RuntimeException: java.lang.ClassNotFoundException: org.jboss.resteasy.client.jaxrs.internal.proxy.ProxyBuilderImpl
    at org.jboss.resteasy.client.jaxrs.ProxyBuilder.builder(ProxyBuilder.java:41)
    at org.jboss.resteasy.client.jaxrs.internal.ClientWebTarget.createProxyBuilder(ClientWebTarget.java:107)
    at org.jboss.resteasy.client.jaxrs.internal.ClientWebTarget.proxy(ClientWebTarget.java:94)
    at org.keycloak.admin.client.spi.ResteasyClientClassicProvider.targetProxy(ResteasyClientClassicProvider.java:48)
    at org.keycloak.admin.client.token.TokenManager.<init>(TokenManager.java:61)
    at org.keycloak.admin.client.Keycloak.<init>(Keycloak.java:91)
    at org.keycloak.admin.client.KeycloakBuilder.build(KeycloakBuilder.java:152)
    at com.xxx.workxxxxxxxxxxxxxxxx.config.KeycloakConfig.getInstance(KeycloakConfig.java:37)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.KxxxxxxxServiceImpl.getInstance(KxxxxxxxServiceImpl.java:240)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.KxxxxxxxServiceImpl.getRealmResource(KxxxxxxxServiceImpl.java:226)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.KxxxxxxxServiceImpl.importUsers(KxxxxxxxServiceImpl.java:132)
    at com.xxx.workxxxxxxxxxxxxxxxx.service.impl.CxxxxxxxxServiceImpl.savePatients(CxxxxxxxxServiceImpl.java:227)
    ... 10 more
Caused by: java.lang.ClassNotFoundException: org.jboss.resteasy.client.jaxrs.internal.proxy.ProxyBuilderImpl
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:525)
    at org.jboss.resteasy.client.jaxrs.ProxyBuilder.builder(ProxyBuilder.java:35)
    ... 21 more

本地验证操作及结果 #

执行以下命令进入容器并校验类存在：

docker exec -it <docker_id> /bin/bash
jar -tf /root/.m2/repository/org/jboss/resteasy/resteasy-client/4.7.9.Final/resteasy-client-4.7.9.Final.jar | grep ProxyBuilderImpl.class

输出结果：org/jboss/resteasy/client/jaxrs/internal/proxy/ProxyBuilderImpl.class

解决思路 #

1. 类加载器冲突排查 #

• 检查UAT环境中服务运行时是否存在多个版本的Resteasy依赖：在UAT容器内执行find / -name "resteasy-*.jar"，查看是否有重复或版本不一致的包，尤其是resteasy-client和resteasy-core这类核心包
• 验证类加载顺序：在JVM启动参数中添加-verbose:class，查看ProxyBuilderImpl类的加载来源，确认是否从正确的jar包中加载

2. 镜像复制过程完整性校验 #

• 重新推送镜像到UAT仓库，或直接在UAT环境重新构建镜像，排除镜像传输过程中的文件丢失问题
• 对比测试环境和UAT环境中容器内的依赖目录：执行diff命令对比两个环境中/root/.m2/repository/org/jboss/resteasy目录下的文件结构和文件哈希值，确认依赖完全一致

3. Kubernetes环境差异排查 #

• 检查UAT环境AKS集群的镜像拉取策略：确认私有仓库的镜像拉取策略是否为Always，避免拉取到旧的损坏镜像
• 查看Pod的挂载卷配置：确认是否有额外的卷挂载覆盖了容器内的依赖目录，导致运行时无法访问正确的jar包

4. 版本兼容性验证 #

• 确认Keycloak Admin Client版本与Resteasy版本是否匹配：比如Keycloak 18+可能需要更高版本的Resteasy，检查构建文件中的依赖版本对应关系
• 显式指定resteasy-client和resteasy-proxy的版本，避免依赖管理工具自动引入不兼容的版本

内容的提问来源于stack exchange，提问作者Abi Showkath