ElasticSearch2.3.4之Java Api呼叫例子
阿新 • • 發佈：2019-01-28
ElasticSearch2.3.4
| 序號 | 覆蓋功能例子 |
|---|---|
| 1 | 客戶端連結初始化 |
| 2 | filte無評分查詢用法 |
| 3 | query有評分查詢用法 |
| 4 | 單欄位分組用法 |
| 5 | 多欄位分組用法 |
| 6 | 讀取有索引無儲存資料的用法 |
| 7 | 設定指定欄位返回 |
程式碼如下：
package com.curd.es;
import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Client;
import /*** * 每一天的select count(distinct(actid)) from talbe group by date */ public static void countDistinctByField(){ //構造search請求 SearchRequestBuilder search=client.prepareSearch("userlog*").setTypes("logs"); search.setQuery(QueryBuilders.queryStringQuery("@timestamp:[ "+new DateTime(2016, 8, 8, 0, 0, 0).getMillis() +" TO "+new DateTime(2016, 8, 15, 0, 0, 0).getMillis()+"}" )); search.setSize(0); //一級分組欄位 DateHistogramBuilder dateagg = AggregationBuilders.dateHistogram("dateagg"); dateagg.field("@timestamp");//聚合時間欄位 // dateagg.interval(DateHistogramInterval.HOUR);//按小時聚合 dateagg.interval(DateHistogramInterval.DAY);//按天聚合 // dateagg.format("yyyy-MM-dd HH"); //格式化時間 dateagg.format("yyyy-MM-dd"); //格式化時間 dateagg.timeZone("Asia/Shanghai");//設定時區，注意如果程式部署在其他國家使用時，使用Joda-Time來動態獲取時區 new DateTime().getZone() //二級分組欄位 // TermsBuilder twoAgg = AggregationBuilders.terms("stragg").field("actId"); MetricsAggregationBuilder twoAgg = AggregationBuilders.cardinality("stragg").field("actId"); //組裝聚合欄位 dateagg.subAggregation(twoAgg); //向search請求新增 search.addAggregation(dateagg); //獲取結果 SearchResponse r = search.get(); Histogram h = r.getAggregations().get("dateagg"); //得到一級聚合結果裡面的分桶集合 List<Histogram.Bucket> buckets = (List<Histogram.Bucket>) h.getBuckets(); //遍歷分桶集 for(Histogram.Bucket b:buckets){ //讀取二級聚合資料集引用 Aggregations sub = b.getAggregations(); //獲取二級聚合集合 Cardinality agg = sub.get("stragg"); //獲取去重後的值 long value = agg.getValue(); //如果設定日期的format的時候，需要使用keyAsString取出，否則獲取的是UTC的標準時間 System.out.println(b.getKeyAsString() +" " +b.getDocCount()+" "+value); } }
/***
* 獲取search請求的結果，並輸出列印結果資訊
* @param search
* @throws Exception
*/
public static void showResult(SearchRequestBuilder search) throws Exception{
SearchResponse r = search.get();//得到查詢結果
for(SearchHit hits:r.getHits()){
//只能獲取addFields裡面新增的欄位
// System.out.println(hits.getFields().get("userId").getValue());
//預設可會source裡面獲取所需欄位
System.out.println(hits.getSource().get("actId"));
//注意不支援data.subjectName這樣的訪問方式
//System.out.println(hits.getId()+" "+hits.score()+" "+data.get("subjectName"));
//如果是個巢狀json，需要轉成map後，訪問其屬性
// Map data=(Map) hits.getSource().get("data");
// System.out.println(hits.getId()+" "+hits.score()+" "+data.get("subjectName"));
}
long hits=r.getHits().getTotalHits();//讀取命中數量
System.out.println(hits);
}
/***
* 最新版elasticsearch2.3的query測試，結果會評分
* @throws Exception
*/
public static void testQuery() throws Exception{
SearchRequestBuilder search=client.prepareSearch("userlog*").setTypes("logs");
String subjectName="語文";
//注意查詢的時候，支援巢狀的json查詢，通過點符號訪問下層欄位，讀取結果時不支援這種方式
search.setQuery(QueryBuilders.queryStringQuery("+data.subjectName:* -data.subjectName:"+subjectName+" "));
showResult(search);
}
/***
* 最新版的elasticsearch2.3的filterquery測試，結果不會評分
* @throws Exception
*/
public static void testFilter() throws Exception{
SearchRequestBuilder search=client.prepareSearch("userlog*").setTypes("logs");
//第一個引數包含的欄位陣列，第二個欄位排除的欄位陣列
// search.setFetchSource(new String[]{"userId","actId"},null);
// search.addFields("actId","userId"); //另一種寫法
String schoolName="沙河市第三小學";
BoolQueryBuilder boolQuery = QueryBuilders.boolQuery()
.must(QueryBuilders.queryStringQuery("*:*"))
.filter(QueryBuilders.queryStringQuery("+data.subjectName:* +schoolName:"+schoolName).defaultOperator(Operator.AND));
//設定query
search.setQuery(boolQuery);
//列印結果資料
showResult(search);
}
/***
* 兩個欄位分組測試，在時間的維度上加上任意其他的欄位聚合，類似group by field1,field2
* @throws Exception
*/
public static void testTwoAggString() throws Exception{
//構造search請求
SearchRequestBuilder search=client.prepareSearch("userlog*").setTypes("logs");
search.setQuery(QueryBuilders.queryStringQuery("@timestamp:[ "+new DateTime(2016, 8, 10, 0, 0, 0).getMillis()
+" TO "+new DateTime(2016, 8, 11, 0, 0, 0).getMillis()+"}"
));
//一級分組欄位
DateHistogramBuilder dateagg = AggregationBuilders.dateHistogram("dateagg");
dateagg.field("@timestamp");//聚合時間欄位
dateagg.interval(DateHistogramInterval.HOUR);//按小時聚合
dateagg.format("yyyy-MM-dd HH"); //格式化時間
dateagg.timeZone("Asia/Shanghai");//設定時區，注意如果程式部署在其他國家使用時，使用Joda-Time來動態獲取時區 new DateTime().getZone()
//二級分組欄位
TermsBuilder twoAgg = AggregationBuilders.terms("stragg").field("module");
//組裝聚合欄位
dateagg.subAggregation(twoAgg);
//向search請求新增
search.addAggregation(dateagg);
//獲取結果
SearchResponse r = search.get();
Histogram h = r.getAggregations().get("dateagg");
//得到一級聚合結果裡面的分桶集合
List<Histogram.Bucket> buckets = (List<Histogram.Bucket>) h.getBuckets();
//遍歷分桶集
for(Histogram.Bucket b:buckets){
//讀取二級聚合資料集引用
Aggregations sub = b.getAggregations();
//獲取二級聚合集合
StringTerms count = sub.get("stragg");
//如果設定日期的format的時候，需要使用keyAsString取出，否則獲取的是UTC的標準時間
System.out.println(b.getKeyAsString() +" " +b.getDocCount());
System.out.println("=============================================");
for(Terms.Bucket bket:(List<Terms.Bucket>)count.getBuckets()){
System.out.println(bket.getKeyAsString() +" "+bket.getDocCount());
}
System.out.println("************************************************");
}
}
/***
* 一個欄位聚合，類似資料庫的group by field1
* @param field 測試聚合的欄位
* @throws Exception
*/
public static void testOneAggString(String field)throws Exception{
//構造search請求
SearchRequestBuilder search=client.prepareSearch("userlog*").setTypes("logs");
//查詢昨天的資料
search.setQuery(QueryBuilders.queryStringQuery("@timestamp:[ "+new DateTime(2016, 8, 10, 0, 0, 0).getMillis()
+" TO "+new DateTime(2016, 8, 11, 0, 0, 0).getMillis()+"}"
));
//聚合構造
TermsBuilder termsBuilder = AggregationBuilders.terms("agg").field(field);
//新增到search請求
search.addAggregation(termsBuilder);
//獲取結果
SearchResponse searchResponse = search.get();
//獲取agg標識下面的結果
Terms agg1 = searchResponse.getAggregations().get("agg");
//獲取bucket
List<Terms.Bucket> buckets = (List<Terms.Bucket>) agg1.getBuckets();
long sum=0;
for(Terms.Bucket b:buckets){
Aggregations sub = b.getAggregations();
System.out.println(b.getKeyAsString()+" "+b.getDocCount());
sum+=b.getDocCount();
}
System.out.println("總數："+sum);
}
}