I tried browsing some logs using the command:

java -Dcom.arjuna.ats.arjuna.common.ObjectStoreEnvironmentBean.objectStoreDir=<path to logs> com.arjuna.ats.arjuna.tools.log.LogBrowser

This gives an interactive command line. I then had a go at listing some logs using:

-> select AtomicAction
-> ls

The tool does not find any logs even though there are entries in the directory:

<path_ to_logs>/ShadowNoFileLockStore/defaultStore/StateManager/BasicAction/TwoPhaseCoordinator/AtomicAction

The problem is that the LogBrowser.listLogs operation uses the the type (AtomicAction) as the parameter to the call StoreManager.getRecoveryStore().allObjUids(type, buff)) but the actual type of an AtomicAction log is "/StateManager/BasicAction/TwoPhaseCoordinator/AtomicAction";