On Windows `File.delete()` causes to file to be modified first of all.
with the high polling interval (`fixedDelay(1)`) there is a chance
to pick the same file from the local directory again, since the
`AbstractPersistentAcceptOnceFileListFilter` is based on the `lastModified`
* Do not delete files manually at all - just rely on the `clean()`
with the `@Before`
**Cherry-pick to 5.0.x**
# Conflicts:
# spring-integration-ftp/src/test/java/org/springframework/integration/ftp/inbound/RotatingServersTests.java
c1dd6187e3