How to avoid using same data in parallel execution

Question

This question is similar to How to manage application data when running multiple tests in parallel?

But I want to know if there's a way or listener in testNG that will lock certain method when running tests in parallel.

What I tried was:

1. Create methods for saving/retrieving data with "java.util.concurrent.Locks"
2. Add those methods in "beforeInitialize" listener

However, the test instance happens before "beforeInitialize". In short, there's still possibility that it access those methods(with lock) at the same time, using different instance.

Edit (1) : Added sample code I used to log and retrieve used data

    public static List<String> unitsReturned(){
        String listStr = getProperty("UNITS_RETURNED");
        if(listStr.equals("UNITS_RETURNED"))
            return new ArrayList<>();
        return textFormatter.getListfromStringDelimiterNonTrimmed(listStr, ",");
    }
    
    public static void logUnitReturned(String unitName) {
        String listStr = getProperty("UNITS_RETURNED");
        if(listStr.equals("UNITS_RETURNED"))
            setProperty("UNITS_RETURNED", unitName);
        else
            setProperty("UNITS_RETURNED", getProperty("UNITS_RETURNED")+","+unitName);
    }