Map<String, Object> sourceMap = new HashMap<>();
        sourceMap.put("string", "test");
        sourceMap.put("integer", 42);
        sourceMap.put("long", 100L);
        sourceMap.put("double", 3.14);
        sourceMap.put("boolean", false);
        sourceMap.put("null_value", null);
        sourceMap.put("nested", nestedMap);

        event.setSourceMap(sourceMap);

        DocMap docMap = new DocMap(parentMap);

        Map<String, Object> sourceMap = new HashMap<>();
        sourceMap.put("key1", "value1");
        sourceMap.put("key2", "value2");
        sourceMap.put("key3", "value3");

        docMap.putAll(sourceMap);

        assertEquals(3, docMap.size());
        assertEquals("value1", docMap.get("key1"));

    ImmutableBiMap<String, String> specialCases =
        ImmutableBiMap.<String, String>builder()
            .put("CDN_LOOP", "CDN-Loop")
            .put("ETAG", "ETag")
            .put("SOURCE_MAP", "SourceMap")
            .put("SEC_CH_UA_WOW64", "Sec-CH-UA-WoW64")
            .put("SEC_WEBSOCKET_ACCEPT", "Sec-WebSocket-Accept")
            .put("SEC_WEBSOCKET_EXTENSIONS", "Sec-WebSocket-Extensions")

     *
     * @param sourceMap The source map containing the date field.
     * @param name The name of the date field.
     * @return The Date object, or null if the field doesn't contain a valid date.
     */
    protected Date getDateFromSource(final Map<String, Object> sourceMap, final String name) {
        final Object obj = sourceMap.get(name);
        if (obj instanceof Date) {