elasticsearch创建索引报错

Q：安装ik分词器1.2.9 后，使用head插件创建索引报错

{
"error": "IndexCreationException[[email] failed to create index]; nested: NoClassDefFoundError[org/apache/http/client/ClientProtocolException]; nested: ClassNotFoundException[org.apache.http.client.ClientProtocolException]; ",
"status": 500 }

A：根据其提示，发现有2种情况，一是jdk的版本不对，一是少了jar包。