Spring Batch thread-safe Map job repository
<p>the <a href="https://docs.spring.io/spring-batch/reference/html/configureJob.html" rel="nofollow">Spring Batch docs</a> say of the Map-backed job repository: </p>

<blockquote>
  <p>Note that the in-memory repository is volatile and so does not allow restart between JVM instances. It also cannot guarantee that two job instances with the same parameters are launched simultaneously, and is not suitable for use in a multi-threaded Job, or a locally partitioned Step. So use the database version of the repository wherever you need those features.</p>
</blockquote>

<p>I would like to use a Map job repository, and I do not care about restarting, prevention of concurrent job executions, etc. but I <strong>do</strong> care about being able to use multi-threading and local partitioning.</p>

<p>My batch application has some partitioned steps, and at first glance it seems to run just fine with a Map-backed job repository. </p>

<p>What is the reason it said to be not possible with MapJobRepositoryFactoryBean? Looking at the implementation of Map DAOs, they are using ConcurrentHashMap. Is this not thread-safe ?</p>