[MIME4J-299] Allow to access Header as a map

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.8.5
• Fix Version/s: 0.8.6
• Component/s: dom
• Assignee: Unassigned
• Reporter: Benoit Tellier
• Created: 25/May/21 00:10
• Updated: 20/Jun/21 02:46
• Resolved: 20/Jun/21 02:46

Description

Today complex code is required to group headers by name:

    static ImmutableMap<String, String> toHeaderMap(Header header) {
        Function<Map.Entry<String, Collection<Field>>, String> bodyConcatenator = fieldListEntry -> fieldListEntry.getValue()
            .stream()
            .map(Field::getBody)
            .map(MimeUtil::unscrambleHeaderValue)
            .collect(Collectors.toList())
            .stream()
            .collect(Collectors.joining(JMAP_MULTIVALUED_FIELD_DELIMITER));

        return Multimaps.index(header.getFields(), Field::getName)
            .asMap()
            .entrySet()
            .stream()
            .collect(Guavate.toImmutableMap(Map.Entry::getKey, bodyConcatenator));
    }

Carrying over the header map can get this way simpler:

        static ImmutableMap<String, String> toHeaderMap(Header header) {
            return header.getFieldsAsMap()
                .entrySet()
                .stream()
                .collect(Guavate.toImmutableMap(Map.Entry::getKey,
                    entry -> entry.getValue().stream()
                        .map(Field::getBody)
                        .map(body -> DecoderUtil.decodeEncodedWords(body, DecodeMonitor.SILENT))
                        .collect(Collectors.joining(JMAP_MULTIVALUED_FIELD_DELIMITER))));
        }