elasticsearch5.4.3异常解决

首先说明一下，刚开始学习时我本地jdk版本是1.7，Java客户端maven配置如下

<dependency> <groupId>org.elasticsearch.client</groupId> <artifactId>transport</artifactId> <version>5.4.1</version> </dependency> <dependency> <groupId>org.elasticsearch</groupId> <artifactId>elasticsearch</artifactId> <version>5.4.1</version> </dependency>这样会报错，提示版本兼容方面的错误。

于是把elasticsearch.client版本换到2.几，还是会报错。

最终的解决方案是jdk升级到1.8，elasticsearch.client版本使用5.4.1。我看网上的资料有的说是elasticsearch5在jdk1.7环境下也能运行，不知道是怎么配置的，看官网的文档描述如下（https://www.elastic.co/guide/en/elasticsearch/reference/5.4/setup.html）

Java (JVM) Versionedit

Elasticsearch is built using Java, and requires at least Java 8 in order to run. Only Oracle’s Java and the OpenJDK are supported. The same JVM version should be used on all Elasticsearch nodes and clients.

We recommend installing Java version 1.8.0_131 or later. Elasticsearch will refuse to start if a known-bad version of Java is used.

也就是说jdk1.8是必须的。

出错场景1：

使用字段进行聚合操作；

eclipse控制台错误信息：

java.lang.IllegalArgumentException: Fielddata is disabled on text fields by default. Set fielddata=true on [result] in order to load fielddata in memory by uninverting the inverted index. Note that this can however use significant memory. Alternatively use a keyword field instead.

解决方法：

PUT /your_index/_mapping/your_type?update_all_types { "properties": { "your_fields": { "type": "text", "fielddata": true } } }返回

{ "acknowledged": true }

出错场景2：删除索引超时

DELETE /my_store返回504 timeout

以为是命令错了或者版本的问题，各种试，最后发现是老爷机的内存被吃光了 =_=!