unsupportedoperation

I try to add objects to a List<String> instance but it throws an UnsupportedOperationException. Does anyone know why? My Java code: String[] membersArray = request.getParameterValues(‘members’); List<String> membersList = Arrays.asList(membersArray); for (String member : membersList) { Person person = Dao.findByName(member); List<String> seeAlso; seeAlso = person.getSeeAlso(); if (!seeAlso.contains(groupDn)){ seeAlso.add(groupDn); person.setSeeAlso(seeAlso); } } The error message: java.lang.UnsupportedOperationException java.util.AbstractList.add(Unknown … Read more