Stop using cached component in _analyze API

Add javadoc some methods Closes elastic#19827

Author: johtani

core/src/main/java/org/elasticsearch/index/analysis/AnalysisRegistry.java

@@ -73,6 +73,12 @@ public AnalysisRegistry(Environment environment,
  this.analyzers = unmodifiableMap(analyzers);
  }
 
+ /**
+ * Returns a {@link Settings} by groupName from {@link IndexSettings} or a default {@link Settings}
+ * @param indexSettings an index settings
+ * @param groupName tokenizer/token filter/char filter name
+ * @return {@link Settings}
+ */
  public static Settings getSettingsFromIndexSettings(IndexSettings indexSettings, String groupName) {
  Settings settings = indexSettings.getSettings().getAsSettings(groupName);
  if (settings.isEmpty()) {
@@ -154,7 +160,14 @@ public AnalysisService build(IndexSettings indexSettings) throws IOException {
  return new AnalysisService(indexSettings, analyzierFactories, tokenizerFactories, charFilterFactories, tokenFilterFactories);
  }
 
-
+ /**
+ * Returns a registered {@link TokenizerFactory} provider by {@link IndexSettings}
+ * or a registered {@link TokenizerFactory} provider by predefined name
+ * or <code>null</code> if the tokenizer was not registered
+ * @param tokenizer global or defined tokenizer name
+ * @param indexSettings an index settings
+ * @return {@link TokenizerFactory} provider or <code>null</code>
+ */
  public AnalysisProvider<TokenizerFactory> getTokenizerProvider(String tokenizer, IndexSettings indexSettings) {
  final Map<String, Settings> tokenizerSettings = indexSettings.getSettings().getGroups("index.analysis.tokenizer");
  if (tokenizerSettings.containsKey(tokenizer)) {
@@ -165,6 +178,14 @@ public AnalysisProvider<TokenizerFactory> getTokenizerProvider(String tokenizer,
  }
  }
 
+ /**
+ * Returns a registered {@link TokenFilterFactory} provider by {@link IndexSettings}
+ * or a registered {@link TokenFilterFactory} provider by predefined name
+ * or <code>null</code> if the tokenFilter was not registered
+ * @param tokenFilter global or defined tokenFilter name
+ * @param indexSettings an index settings
+ * @return {@link TokenFilterFactory} provider or <code>null</code>
+ */
  public AnalysisProvider<TokenFilterFactory> getTokenFilterProvider(String tokenFilter, IndexSettings indexSettings) {
  final Map<String, Settings> tokenFilterSettings = indexSettings.getSettings().getGroups("index.analysis.filter");
  if (tokenFilterSettings.containsKey(tokenFilter)) {
@@ -185,6 +206,14 @@ public AnalysisProvider<TokenFilterFactory> getTokenFilterProvider(String tokenF
  }
  }
 
+ /**
+ * Returns a registered {@link CharFilterFactory} provider by {@link IndexSettings}
+ * or a registered {@link CharFilterFactory} provider by predefined name
+ * or <code>null</code> if the charFilter was not registered
+ * @param charFilter global or defined charFilter name
+ * @param indexSettings an index settings
+ * @return {@link CharFilterFactory} provider or <code>null</code>
+ */
  public AnalysisProvider<CharFilterFactory> getCharFilterProvider(String charFilter, IndexSettings indexSettings) {
  final Map<String, Settings> tokenFilterSettings = indexSettings.getSettings().getGroups("index.analysis.char_filter");
  if (tokenFilterSettings.containsKey(charFilter)) {