In Camel File component, the FileConsumer.pollDirectory() call several methods that are java.ioFile.* 

java.io.File.length()
java.io.File.lastModified()
java.io.File.isDirectory()
and another
java.io.File.isDirectory()

Probably java.io.File is inefficient. Java 7's java.nio.file package with Files.newDirectoryStream() is much more efficient and should be used these days.

https://www.rgagnon.com/javadetails/java-get-directory-content-faster-with-many-files.html

found a factor of 460x performance improvement on large directories with java.nio.file vs java.io.File.

Is there a good reason why we don't use java.nio.file.* to improve performance?