int productionModifier = 0;
Iterator propertyIterator = getPropertiesIterator();
while (propertyIterator.hasNext()) {
Property property = (Property) propertyIterator.next();
if (property instanceof ModifyProduction) {
ModifyProduction increaseProduction = (ModifyProduction) property;
productionModifier = productionModifier + increaseProduction.getModifier();
}
}
return productionModifier;
}