// Test that method is case sensitive (as per implementation)
        assertNull(languageHelper.getSupportedLanguage("JA"));
        assertNull(languageHelper.getSupportedLanguage("EN"));
        assertEquals("ja", languageHelper.getSupportedLanguage("ja"));
        assertEquals("en", languageHelper.getSupportedLanguage("en"));
    }

    @Test
    public void test_updateDocument_emptyLangFields() {

        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja-jp" }));
        assertArrays(new String[] { "ja" }, fessConfig.normalizeQueryLanguages(new String[] { "ja_JP" }));
        assertArrays(new String[] { "ja", "zh-cn" }, fessConfig.normalizeQueryLanguages(new String[] { "ja", "zh" }));

        value = " ja ";
        assertEquals("ja", systemHelper.normalizeLang(value));

        value = "ja-JP";
        assertEquals("ja", systemHelper.normalizeLang(value));

        value = "ja_JP";
        assertEquals("ja", systemHelper.normalizeLang(value));

        value = "ja_JP_AAA";
        assertEquals("ja", systemHelper.normalizeLang(value));

        value = "zh";

    @Test
    public void test_serializeParameters() {
        RequestParameter[] params = new RequestParameter[] { new RequestParameter("q", new String[] { "test" }),
                new RequestParameter("lang", new String[] { "en", "ja" }) };
        String encoded = searchHelper.serializeParameters(params);
        assertNotNull(encoded);
        byte[] compressed = Base64.getUrlDecoder().decode(encoded);

        value.clear();

        List<String> keys = Arrays.asList("test_2", "test_0", "lang", "test_1");
        value.put(keys.get(0), true);
        value.put(keys.get(1), 1000);
        value.put(keys.get(2), "ja");
        value.put(keys.get(3), "str");
        docMap = new DocMap(value);
        assertFalse(docMap.isEmpty());

        Set<Map.Entry<String, Object>> actual = docMap.entrySet();

```

**Optional configurations:**

If you create online help documentation:
```properties
online.help.supported.langs=ja,sv  # Add your language
```

If you have forum support:
```properties
forum.supported.langs=en,ja,sv  # Add your language
```

			<arg>"fess"</arg>
			<arg>"it/protwords.txt"</arg>
		</postConstruct>
		<postConstruct name="addConfigFile">
			<arg>"fess"</arg>
			<arg>"ja/kuromoji.txt"</arg>
		</postConstruct>
		<postConstruct name="addConfigFile">
			<arg>"fess"</arg>
			<arg>"ja/mapping.txt"</arg>
		</postConstruct>
		<postConstruct name="addConfigFile">
			<arg>"fess"</arg>
			<arg>"ko/nori.txt"</arg>
		</postConstruct>

          "type": "mapping",
          "mappings_path": "${fess.dictionary.path}fa/mapping.txt"
        },
        "mapping_ja_filter": {
          "type": "mapping",
          "mappings_path": "${fess.dictionary.path}ja/mapping.txt"
        },
        "mapping_filter": {
          "type": "mapping",
          "mappings_path": "${fess.dictionary.path}mapping.txt"
        },
        "traditional_chinese_convert": {

                return 10;
            }

            @Override
            public String getQueryDefaultLanguages() {
                return "en,ja";
            }

            @Override
            public String getQueryLanguageMapping() {
                return "";
            }

            @Override

            public String getQueryLanguageMapping() {
                return "en:en,ja:ja";
            }

            @Override
            public String getQueryDefaultLanguages() {
                return "en,ja";
            }

            @Override
            public String[] getQueryAdditionalResponseFields(String... fields) {
                return fields;
            }

            @Override