ElasticSearch（ES） 是开源（apache 2 授权）、分布式、REST风格、搜索引擎基于Lucene的实现。

Jest是一个为ES操作Java Http Rest 的客户端，及使用它来捕获、存储以及操作数据。

Jest提供JavaAPI，可以很好的处理Java对象序列。通过Jest，可以获取普通的Java对象并在ES中为它们建立索引。然后使用ES的搜索API，将您的返回的对象转换Java对象。

可以通过来阅读ES和Jest

安装说明

 Jest Maven 托管在 .

配置pom.xml 文件

    
     .. 
        
      
       sonatype
         
      
       Sonatype Groups
         
      
       https://oss.sonatype.org/content/groups/public/
       
     ..
    

添加依赖

      
     
      io.searchbox
       
     
      jest
       
     
      0.0.3
     
    

 更新日志

Jest 有一个简单的实例，请看这里

使用Jest之前要需要一个JestClient

// Configuration ClientConfig clientConfig = new ClientConfig(); LinkedHashSet
    
      servers = new LinkedHashSet
     
      (); servers.add("http://localhost:9200"); clientConfig.getProperties().put(ClientConstants.SERVER_LIST, servers); clientConfig.getProperties().put(ClientConstants.IS_MULTI_THREADED, true); // Construct a new Jest client according to configuration via factory JestClientFactory factory = new JestClientFactory(); factory.setClientConfig(clientConfig); JestClient client = factory.getObject();
     
    

JestClient使用单例模式，构造器是私有。

 

开始创建索引

通过Jest创建Index是一件很轻松的事

client.execute(new CreateIndex("articles"));

设置ES参数，可以通过JSON完成

String settings = "\"settings\" : {\n" +                "        \"number_of_shards\" : 5,\n" +                "        \"number_of_replicas\" : 1\n" +                "    }\n";client.execute(new CreateIndex("articles"), settings)

或者通过SetingsBuilder，添加ES依赖设置API

import org.elasticsearch.common.settings.ImmutableSettings;..ImmutableSettings.Builder settingsBuilder = ImmutableSettings.settingsBuilder();settings.put("number_of_shards",5); settings.put("number_of_replicas",1); client.execute(new CreateIndex("articles"), settingsBuilder.build().getAsMap());

 

索引文档

ES请求索引数据JSON格式，通过Jest的几种方法创建文档索引

1.JSON 字符串

String source = "{\"user\":\"kimchy\"}";

2.ES JSONBuilder

String source = jsonBuilder().startObject().field("user", "kimchy").field("postDate", "date").field("message", "trying out Elastic Search").endObject().string();

3.Map

Map
    
      source = new LinkedHashMap
     
      ()source.put("user", "kimchy");
     
    

4.POJO

Article source = new Article();source.setAuthor("John Ronald Reuel Tolkien");source.setContent("The Lord of the Rings is an epic high fantasy novel");

指定索引数据生成索引 为twitter index with type tweet

Index index = new Index.Builder(source).index("twitter").type("tweet").build();client.execute(index);

 可以明确指定索引Id

Index index = new Index.Builder(source).index("twitter").type("tweet").id("1").build();client.execute(index);

也可以通过Jest注解的方式指定索引Id

class Article {@JestIdprivate Long documentId;}

 如果JestId 是null，则有ES自动生成Id。

 

搜索文档

通过Json 字符串搜索

String query = "{\n" +            "    \"query\": {\n" +            "        \"filtered\" : {\n" +            "            \"query\" : {\n" +            "                \"query_string\" : {\n" +            "                    \"query\" : \"test\"\n" +            "                }\n" +            "            },\n" +            "            \"filter\" : {\n" +            "                \"term\" : { \"user\" : \"kimchy\" }\n" +            "            }\n" +            "        }\n" +            "    }\n" +            "}"; Search search = new Search(query);// multiple index or types can be added.search.addIndex("twitter");search.addType("tweet");            JestResult result = client.execute(search);

使用SearchSourceBuilder

SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();searchSourceBuilder.query(QueryBuilders.matchQuery("user", "kimchy"));Search search = new Search(searchSourceBuilder.toString());search.addIndex("twitter");search.addType("tweet");            JestResult result = client.execute(search);

 结果转换成对象

JestResult result = client.execute(search);List
    
      articles = result.getSourceAsObjectList(Article.class);
    

如果要阅读复杂的查询，请这里走

获取索引文档

Get get = new Get.Builder("1").index("twitter").type("tweet").build();JestResult result = client.execute(get);

结果转换成对象

Get get = new Get.Builder("1").index("twitter").type("tweet").build();JestResult result = client.execute(get);Article article = result.getSourceAsObject(Article.class);

更新索引文档

String script = "{\n" +                "    \"script\" : \"ctx._source.tags += tag\",\n" +                "    \"params\" : {\n" +                "        \"tag\" : \"blue\"\n" +                "    }\n" +                "}";client.execute(new Update.Builder(script).index("twitter").type("tweet").id("1").build());

删除文档

client.execute(new Delete.Builder("1").index("twitter").type("tweet").build());

批量操作

通过API批量操作 index/delete 操作，可以大大增加索引速度。

Bulk bulk = new Bulk("twitter", "tweet");bulk.addIndex(new Index.Builder(article1).build());bulk.addIndex(new Index.Builder(article2).build());bulk.addDelete(new Delete.Builder("1").build());client.execute(bulk);

集合批量操作

Bulk bulk = new Bulk("twitter", "tweet");Article article1 = new Article("tweet1");Article article2 = new Article("tweet1");bulk.addIndexList(Arrays.asList(article1, article2););client.execute(bulk);

设置参数

ElasticSearch要求参数来设置属性，如 routing, versioning 操作类型等

比如设置“refresh” 为 “true”

Index index = new Index.Builder("{\"user\":\"kimchy\"}").index("cvbank").type("candidate").id("1").build();index.addParameter(Parameters.REFRESH, true);client.execute(index);

同步操作

Jest http Client 支持 blocking IO asynchronously.

使用Jest 同步操作实例

client.executeAsync(action,new JestResultHandler
    
     () {    @Override    public void completed(JestResult result) {        ... do process result ....    }    @Override    public void failed(Exception ex) {       ... catch exception ...    }});
    

配置在同一网段内发下其它节点设置

//enable host discoveryclientConfig.getProperties().put(ClientConstants.DISCOVERY_ENABLED, true);      //booleanclientConfig.getProperties().put(ClientConstants.DISCOVERY_FREQUENCY, 1l);      //longclientConfig.getProperties().put(ClientConstants.DISCOVERY_FREQUENCY_TIMEUNIT, TimeUnit.MINUTES); //timeunit

 source