我正在尝试使用docker图像在Flink1.10.1上运行beam（2.21）wordcount示例。运行时作业管理器和taskmanager启动正常，但在写入结果的最后一步失败，出现以下异常：

taskmanager_1  | 2020-07-06 21:18:31,897 WARN  org.apache.flink.runtime.accumulators.AccumulatorRegistry     - Failed to serialize accumulators for task.
taskmanager_1  | java.lang.NoClassDefFoundError: org/apache/beam/runners/core/metrics/MetricUpdates$MetricUpdate
taskmanager_1  |        at java.lang.Class.getDeclaredMethods0(Native Method)
taskmanager_1  |        at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)
taskmanager_1  |        at java.lang.Class.getDeclaredMethod(Class.java:2128)
taskmanager_1  |        at java.io.ObjectStreamClass.getPrivateMethod(ObjectStreamClass.java:1629)
taskmanager_1  |        at java.io.ObjectStreamClass.access$1700(ObjectStreamClass.java:79)
taskmanager_1  |        at java.io.ObjectStreamClass$3.run(ObjectStreamClass.java:520)
taskmanager_1  |        at java.io.ObjectStreamClass$3.run(ObjectStreamClass.java:494)
taskmanager_1  |        at java.security.AccessController.doPrivileged(Native Method)
taskmanager_1  |        at java.io.ObjectStreamClass.<init>(ObjectStreamClass.java:494)
taskmanager_1  |        at java.io.ObjectStreamClass.lookup(ObjectStreamClass.java:391)
taskmanager_1  |        at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1134)
taskmanager_1  |        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:348)
taskmanager_1  |        at java.util.concurrent.ConcurrentHashMap.writeObject(ConcurrentHashMap.java:1413)

任何指针这里可能缺少什么？