Hi, aiden. 看起来是类冲突，按照官方的文档，使用 kafka 时，你应该是不需要引入 flink-core 和 flink-connector-base 的（ https://nightlies.apache.org/flink/flink-docs-release-1.17/docs/connectors/table/kafka/）。如果是因为其他原因需要使用这两个 jar， 你可以使用 mvn dependency::tree 查看一下 "org/apache/kafka/clients/consumer/ConsumerRecord" 是在哪里被重复加载进来，可以exclude 掉非 flink-connector-kafka 的这个类。
aiden <18765295...@163.com> 于2023年7月4日周二 14:23写道： > hi > > 在使用1.17.1版本kafka source时遇到如下异常： > Caused by: java.lang.LinkageError: loader constraint violation: loader > (instance of org/apache/flink/util/ChildFirstClassLoader) previously > initiated loading for a different type with name > "org/apache/kafka/clients/consumer/ConsumerRecord" > at java.lang.ClassLoader.defineClass1(Native Method) > at java.lang.ClassLoader.defineClass(ClassLoader.java:763) > at > java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) > at java.net.URLClassLoader.defineClass(URLClassLoader.java:467) > at java.net.URLClassLoader.access$100(URLClassLoader.java:73) > at java.net.URLClassLoader$1.run(URLClassLoader.java:368) > at java.net.URLClassLoader$1.run(URLClassLoader.java:362) > at java.security.AccessController.doPrivileged(Native Method) > at java.net.URLClassLoader.findClass(URLClassLoader.java:361) > at > org.apache.flink.util.ChildFirstClassLoader.loadClassWithoutExceptionHandling(ChildFirstClassLoader.java:71) > at > org.apache.flink.util.FlinkUserCodeClassLoader.loadClass(FlinkUserCodeClassLoader.java:51) > at java.lang.ClassLoader.loadClass(ClassLoader.java:357) > at java.lang.Class.getDeclaredMethods0(Native Method) > at java.lang.Class.privateGetDeclaredMethods(Class.java:2701) > at java.lang.Class.getDeclaredMethod(Class.java:2128) > at > java.io.ObjectStreamClass.getPrivateMethod(ObjectStreamClass.java:1629) > at java.io.ObjectStreamClass.access$1700(ObjectStreamClass.java:79) > at java.io.ObjectStreamClass$3.run(ObjectStreamClass.java:520) > at java.io.ObjectStreamClass$3.run(ObjectStreamClass.java:494) > at java.security.AccessController.doPrivileged(Native Method) > at java.io.ObjectStreamClass.<init>(ObjectStreamClass.java:494) > at java.io.ObjectStreamClass.lookup(ObjectStreamClass.java:391) > at > java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:681) > at > java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1885) > at > java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1751) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2042) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1573) > at > java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2287) > at > java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2211) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2069) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1573) > at > java.io.ObjectInputStream.defaultReadFields(ObjectInputStream.java:2287) > at > java.io.ObjectInputStream.readSerialData(ObjectInputStream.java:2211) > at > java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:2069) > at > java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1573) > at java.io.ObjectInputStream.readObject(ObjectInputStream.java:431) > at > org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:534) > at > org.apache.flink.util.InstantiationUtil.deserializeObject(InstantiationUtil.java:522) > at > org.apache.flink.util.SerializedValue.deserializeValue(SerializedValue.java:67) > at > org.apache.flink.runtime.operators.coordination.OperatorCoordinatorHolder.create(OperatorCoordinatorHolder.java:471) > at > org.apache.flink.runtime.executiongraph.ExecutionJobVertex.createOperatorCoordinatorHolder(ExecutionJobVertex.java:286) > at > org.apache.flink.runtime.executiongraph.ExecutionJobVertex.initialize(ExecutionJobVertex.java:223) > ... 20 more > 以下是我的部分POM <dependency> > <groupId>org.apache.flink</groupId> > <artifactId>flink-core</artifactId> > <version>1.17.1</version> > </dependency> > <dependency> > <groupId>org.apache.flink</groupId> > <artifactId>flink-connector-kafka</artifactId> > <version>1.17.1</version> > </dependency> > <dependency> > <groupId>org.apache.flink</groupId> > <artifactId>flink-connector-base</artifactId> > <version>1.17.1</version> > </dependency> > > > 看起来像是类加载器异常，需要我修改哪些地方吗 >
