writing a junit test(s) for a method that returns boolean and accepts two params of non-primitive type

I am fairly new to writing Junits in such detail.

The method returns boolean true/false accepts two params of same non-primitive type.

This method does a whole lot of validations by comparing the two instances of the similar type using if else conditions. And few more validations while iterating through the collection based fields of the params .

I tried writing the base scenario, but unclear as to how to do it for the underlying if_conditons. especially with regard to mocking the data.

What I tried and aware: There are lots of methods under AssertClass which I can use to validate, however for this method that return boolean based on quite a bunch of conditions, how do I write? do I have to write individual asserts for each condition under the @Test annotated method? below is my code :

public boolean checkEligblity(A newversion, A currentversion) {
    if (currentversion.getPurchaseOrders().isEmpty())
        return true;
    if (currentversion.getReceiptNotice() != newversion.getReceiptNotice()
            || currentversion.getSizeType() != newversion.getSizeType()
            || currentversion.getNumInPrices() != newversion.getNumInPrices())
        return true;
    boolean storeM = newversion.getReceiptNotice() == PASSED;
    if (currentversion.getOrderInfo() != newversion.getOrderInfo()) {
        if (storeM || containsCustomerString(currentversion.getOrderInfo())
                || containsCustomerString(newversion.getOrderInfo()))
            return true;
    }
    List<PurchaseOrders> newVersionPurchaseOrders = newversion.getPurchaseOrders();
    List<PurchaseOrders> currentVersionPurchaseOrders = currentversion.getPurchaseOrders();
    for (Iterator<PurchaseOrders> newPOIterator = newVersionPurchaseOrders.iterator(); newPOIterator.hasNext();) {
        PurchaseOrders newPO = newPOIterator.next();
        for (Iterator<PurchaseOrders> currentPOIterator = currentVersionPurchaseOrders.iterator(); currentPOIterator
                .hasNext();) {
            PurchaseOrders currentPO = currentPOIterator.next();
            if (newPO.getSku() == currentPO.getSku()
                    && newPO.getSkuId() == currentPO.getSkuId()
                    && newPO.getOrgin() == currentPO.getOrgin()
                    && newPO.getTarget() == currentPO.getTarget()
                    && newPO.getShippingDate()== currentPO.getDepratureDate()) {
                if (currentPO.getStatusCode().equals(newPO.getStatusCode())
                        && currentPO.getItemsInQty().equals(newPO.getItemsInQty())
                        && currentPO.getVendorId().equals(newPO.getVendorId())
                        && currentPO.getCodeInd().equals(newPO.getCodeInd())
                        && currentPO.getPriceType().charAt(0) == newPO.getPriceType().charAt(0)) {
                    boolean matchingFound = true;
                    if (storeM && currentPO.getInbound() != newPO.getInbound()) {
                        matchingFound = false;
                    }
                    if (matchingFound) {
                        newPOIterator.remove();
                        currentPOIterator.remove();
                        break;
                    }
                }
            }
        }
    }
    if (!newVersionPurchaseOrders.isEmpty() || !currentVersionPurchaseOrders.isEmpty()) {
        return true;
    }
    return false;
}
private boolean containsCustomerString(String ticketingInfo) {
    if (orderInfo == null)
        return false;
    if (orderInfo.startsWith(PASS))
        return true;
    return false;
}