StackOverFlowError while creating Mac object on AS400/Java

Answer 1

The issue appears to be

at java.io.Os400FileSystem.list(Native method)
at java.io.File.list(File.java:922)

The Mac.getInstance() code needs to read a folder (File.list) which is being done by the Os400FileSystem.list() method. Apparently that folder is too large.

The first thing you need to check is that the machine is current on PTF's. If the problem remains, then try giving your process more memory (argument to the JAVA/RUNJVA command) to see if you just have a bit too little memory. The defaults were incremented from V5R3 to V5R4.