去官网看了一下，自定义分析器标准格式是：
PUT /my_index
{
    "settings": {
        "analysis": {
            "char_filter": { ... custom character filters ... },//字符过滤器
            "tokenizer": { ... custom tokenizers ... },//分词器
            "filter": { ... custom token filters ... }, //词单元过滤器
            "analyzer": { ... custom analyzers ... }
        }
    }
}
============================实例===========================
PUT /my_index
{
    "settings": {
        "analysis": {
            "char_filter": {
                "&_to_and": {
                    "type": "mapping",
                    "mappings": [ "&=> and "]
            }},
            "filter": {
                "my_stopwords": {
                    "type": "stop",
                    "stopwords": [ "the", "a" ]
            }},
            "analyzer": {
                "my_analyzer": {
                    "type": "custom",
                    "char_filter": [ "html_strip", "&_to_and" ],
                    "tokenizer": "standard",
                    "filter": [ "lowercase", "my_stopwords" ]
            }}
}}}


============================实例===========================
比如自定义好的analyzer名字是my_analyzer,在此索引下的某个新增字段应用此分析器
PUT /my_index/_mapping
{
   "properties":{
        "username":{
             "type":"text",
              "analyzer" : "my_analyzer"
         },
        "password" : {
          "type" : "text"
        }
    
  }
}
=================插入数据====================
PUT /my_index/_doc/1
{
  "username":"The quick & brown fox ",
   "password":"The quick & brown fox "


}
====username采用自定义分析器my_analyzer,password采用默认的standard分析器==
===验证
GET /index_v1/_analyze
{
  "field":"username",
  "text":"The quick & brown fox"
}

GET /index_v1/_analyze
{
  "field":"password",
  "text":"The quick & brown fox"
}
//官网权威指南是真的讲得好，虽然版本太老，Elasticsearch 2.x 版本，一些api已经不适用了，自定义分析器地址：https://www.elastic.co/guide/cn/elasticsearch/guide/cn/custom-analyzers.html