elasticsearch 学习笔记(2)-客户端编程【原创】

客户端编程可以自己封装json http请求，也可以采用es客户端API。这里介绍API方式。
1. 初始化Client

public void init() {
		String clusterName="elasticsearch";
		String ip= "192.168.180.15";
		Settings settings = Settings.settingsBuilder()
		        .put("cluster.name", clusterName)
		        .build();
		try {
		    client = TransportClient.builder()
		            .settings(settings).build()
		            .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(ip),9300));
		    createMapping("index", "type");		} catch (Exception e) {
		   	e.printStackTrace();
		}
	}

分词映射：

private void createMapping(String indices,String mappingType)throws Exception{
	new XContentFactory();
		XContentBuilder builder=XContentFactory.jsonBuilder()
		.startObject()
			.startObject(mappingType)
				.startObject("properties")
					.startObject("XXX").field("type", "string").field("store", "yes").field("index","not_analyzed").endObject()
					.startObject("YYY").field("type", "string").field("store", "yes").field("analyzer", "ik").endObject()
					.startObject("ZZZ").field("type", "double").field("store", "yes").field("index","not_analyzed").endObject()				.endObject()
			.endObject()
		.endObject();
		PutMappingRequest mapping = Requests.putMappingRequest(indices).type(mappingType).source(builder);
		client.admin().indices().putMapping(mapping).actionGet();
	}

XXX，YYY，ZZZ代表业务字段，因为只演示技术，所以以虚拟字段代替。

2. 创建索引

//其中的map为业务数据，key=XXX/YYY/ZZZ
private void createChineseIndex(String id, Map<String, Object> map) throws Exception{
		client.prepareIndex("index", "type", id).setSource(generateJson(map))
		.execute().actionGet();
	}
//生成json请求数据
private String generateJson(Map<String, Object> map) {
		String json = "";
		try {
			XContentBuilder contentBuilder = XContentFactory.jsonBuilder()
					.startObject();
			for(String key:map.keySet()){
				contentBuilder.field(key, map.get(key));
			}
			json = contentBuilder.endObject().string();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return json;
	}

3. 分组统计

private String searchGoodsName(String goodsName) {
		String fullGoodsName=null;
		SearchResponse response = client.prepareSearch("index")
				.setTypes("type")
				.setSearchType(SearchType.COUNT)
				.setQuery(QueryBuilders.termQuery("XXX", goodsName))
				.addAggregation(AggregationBuilders.terms("gCount").field("YYY"))
				.execute().actionGet();
		StringTerms gNameTerms = (StringTerms) response.getAggregations().get("gCount");
		
		Iterator<Bucket> gradeBucketIt = gNameTerms.getBuckets().iterator();
		
		while(gradeBucketIt.hasNext())
		{
			Bucket gradeBucket = gradeBucketIt.next();
			System.out.println("名称:"+gradeBucket.getKey() + ",数量" + gradeBucket.getDocCount());
			if(fullGoodsName==null){
				fullGoodsName=gradeBucket.getKey().toString();
			}
		}
		
		return fullGoodsName;
	}

4.排序

SearchResponse response = client.prepareSearch("index")
				.setTypes("type")
				.setSearchType(SearchType.DFS_QUERY_AND_FETCH)
				.setQuery(QueryBuilders.termQuery("XXX", name)) // Query
				.setPostFilter(QueryBuilders.termQuery("YYY", value))
				.addSort("ZZZ", SortOrder.ASC)                       // Filter
				.setFrom(0).setSize(60).execute().actionGet();

5.简单查询

SearchResponse response = client.prepareSearch("index")
				.setTypes("type")
				.setSearchType(SearchType.DFS_QUERY_AND_FETCH)
				.setQuery(QueryBuilders.termQuery("XXX", name)) // Query
				.setPostFilter(QueryBuilders.termQuery("YYY", value))
				.setFrom(0).setSize(60).setExplain(false).execute().actionGet();

6.关闭客户端

public void close() {
		client.close();
	}