工作流报redis序列化错误java.lang.NullPointerException

一、该问题的重现步骤是什么？

1.在blade-dev.yaml配置文件中，修改redis序列化方式为json

2. 启动请假流程后，在待办事务功能，点查询报如下错误:

org.springframework.data.redis.serializer.SerializationException: Could not write JSON: (was java.lang.NullPointerException) (through reference chain: org.flowable.engine.impl.persistence.entity.ProcessDefinitionEntityImpl["identityLinks"]); nested exception is com.fasterxml.jackson.databind.JsonMappingException: (was java.lang.NullPointerException) (through reference chain: org.flowable.engine.impl.persistence.entity.ProcessDefinitionEntityImpl["identityLinks"])

at org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer.serialize(GenericJackson2JsonRedisSerializer.java:120)

at org.springframework.data.redis.serializer.DefaultRedisElementWriter.write(DefaultRedisElementWriter.java:43)

at org.springframework.data.redis.serializer.RedisSerializationContext$SerializationPair.write(RedisSerializationContext.java:287)

at org.springframework.data.redis.cache.RedisCache.serializeCacheValue(RedisCache.java:244)

at org.springframework.data.redis.cache.RedisCache.put(RedisCache.java:150)

at org.springblade.core.cache.utils.CacheUtil.get(CacheUtil.java:197)

at org.springblade.core.cache.utils.CacheUtil.get(CacheUtil.java:168)

at org.springblade.flow.engine.utils.FlowCache.getProcessDefinition(FlowCache.java:53)

at org.springblade.flow.business.service.impl.FlowBusinessServiceImpl.lambda$buildFlowTaskList$2(FlowBusinessServiceImpl.java:301)

at java.lang.Iterable.forEach(Iterable.java:75)

at org.springblade.flow.business.service.impl.FlowBusinessServiceImpl.buildFlowTaskList(FlowBusinessServiceImpl.java:283)

at org.springblade.flow.business.service.impl.FlowBusinessServiceImpl.selectTodoPage(FlowBusinessServiceImpl.java:100)

二、你期待的结果是什么？实际看到的又是什么？

三、你正在使用的是什么产品，什么版本？在什么操作系统上？

四、请提供详细的错误堆栈信息，这很重要。

五、若有更多详细信息，请在下面提供。