BATCH_STEP_EXECUTION_CONTEXT에 저장하는 데이터의 직렬화 라이브러리가 XStream → Jackson 으로 변경되면서 포맷이 바뀌어서 호환이 안된다.
Before Spring Batch 4, the default serialization mechanism for the ExecutionContext was via XStream. Now it uses Jackson by default which is not compatible with the old serialization format. We still have the old version available (XStreamExecutionContextStringSerializer) but you'll need to configure it yourself by implementing a BatchConfigurer and overriding the configuration in the JobRepositoryFactoryBean.
For the record, this is related to this issue: https://jira.spring.io/browse/BATCH-2575.