String () { StringBuilder result = new StringBuilder(); result.append("[").append(getName()).append("]@"); result.append(Integer.toHexString(hashCode())); result.append(" : "); result.append(getMainType().getTypeName()); List<String> nonDefaultTypes = myPerRelationTypes.entrySet().stream() .filter(e -> e.getValue() == getMainType()) .map(e -> e.getKey() + ":" + e.getValue()) .collect(Collectors.toList()); if (!nonDefaultTypes.isEmpty()) { result.append(nonDefaultTypes); } return result.toString(); }