title: ElasticSearch - unrecognized character escape
body: <p>I have the following exception:</p>
  
  <pre><code>[index {[mmm][info][1484211], source[
  {"content":"В 1966 г. М. Флинном (Flynn) был предложен следующий подход к классификации архитектур вычислительных систем. В основу было положено понятие потока, под которым понимается последовательность элементов, команд или данных, обрабатываемая процессором. Соответствующая система классификации основана на рассмотрении числа потоков инструкций и потоков данных и описывает четыре базовых класса (табл. 2.8, рис. 2.48). Коротко рассмотрим отличительные особенности каждой из архитектур. Таблица 2.8 Классификация Флинна Поток данных Поток команд одиночный множественный"}]}]
  MapperParsingException[failed to parse [content]]; nested: JsonParseException[Unrecognized character escape '(' (code 40)
   at [Source: org.elasticsearch.common.io.stream.InputStreamStreamInput@5958b83d; line: 1, column: 46]];
      at org.elasticsearch.index.mapper.FieldMapper.parse(FieldMapper.java:339)
      at org.elasticsearch.index.mapper.DocumentParser.parseObjectOrField(DocumentParser.java:314)
      at org.elasticsearch.index.mapper.DocumentParser.parseValue(DocumentParser.java:441)
      at org.elasticsearch.index.mapper.DocumentParser.parseObject(DocumentParser.java:267)
      at org.elasticsearch.index.mapper.DocumentParser.innerParseDocument(DocumentParser.java:127)
      at org.elasticsearch.index.mapper.DocumentParser.parseDocument(DocumentParser.java:79)
      at org.elasticsearch.index.mapper.DocumentMapper.parse(DocumentMapper.java:318)
      at org.elasticsearch.index.shard.IndexShard.prepareIndex(IndexShard.java:551)
      at org.elasticsearch.index.shard.IndexShard.prepareIndex(IndexShard.java:542)
      at org.elasticsearch.action.support.replication.TransportReplicationAction.prepareIndexOperationOnPrimary(TransportReplicationAction.java:1049)
      at org.elasticsearch.action.support.replication.TransportReplicationAction.executeIndexRequestOnPrimary(TransportReplicationAction.java:1060)
      at org.elasticsearch.action.index.TransportIndexAction.shardOperationOnPrimary(TransportIndexAction.java:170)
      at org.elasticsearch.action.support.replication.TransportReplicationAction$PrimaryPhase.performOnPrimary(TransportReplicationAction.java:579)
      at org.elasticsearch.action.support.replication.TransportReplicationAction$PrimaryPhase$1.doRun(TransportReplicationAction.java:452)
      at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
      at java.lang.Thread.run(Thread.java:745)
  Caused by: com.fasterxml.jackson.core.JsonParseException: Unrecognized character escape '(' (code 40)
   at [Source: org.elasticsearch.common.io.stream.InputStreamStreamInput@5958b83d; line: 1, column: 46]
      at com.fasterxml.jackson.core.JsonParser._constructError(JsonParser.java:1581)
      at com.fasterxml.jackson.core.base.ParserMinimalBase._reportError(ParserMinimalBase.java:533)
      at com.fasterxml.jackson.core.base.ParserMinimalBase._handleUnrecognizedCharacterEscape(ParserMinimalBase.java:510)
      at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._decodeEscaped(UTF8StreamJsonParser.java:3171)
      at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._finishString2(UTF8StreamJsonParser.java:2456)
      at com.fasterxml.jackson.core.json.UTF8StreamJsonParser._finishAndReturnString(UTF8StreamJsonParser.java:2411)
      at com.fasterxml.jackson.core.json.UTF8StreamJsonParser.getText(UTF8StreamJsonParser.java:285)
      at org.elasticsearch.common.xcontent.json.JsonXContentParser.text(JsonXContentParser.java:88)
      at org.elasticsearch.common.xcontent.support.AbstractXContentParser.textOrNull(AbstractXContentParser.java:194)
      at org.elasticsearch.index.mapper.core.StringFieldMapper.parseCreateFieldForString(StringFieldMapper.java:354)
      at org.elasticsearch.index.mapper.core.StringFieldMapper.parseCreateField(StringFieldMapper.java:294)
      at org.elasticsearch.index.mapper.FieldMapper.parse(FieldMapper.java:331)
      ... 17 more
  </code></pre>
  
  <p>Already several ours I cant find out what is the problem. As I see all special characters are escaped however I constantly get this exception. I use elasticsearch 2.1. I tried also with 1.4 result is the same. How to fix it?</p>