Elasticsearch
Github源码：https://github/Mengzuozhu/es-demo
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from size 分页-Java示例Scroll 分页-Java示例Search After分页-Java示例 ES分页方式对比参考： /andybegin/article/details/83864171
5.6官方Search After文档
7.x官方Search After文档
分页方式简述缺点from size浅分页情况下，可以考虑使用；深度分页情况下，性能较差Scroll基于历史快照和上一页的scroll_id，查询下一页；● 滚屏翻页，快照比较占内存；● 不适合实时搜索和跳页需求Search After1. 需要排序，官方（5.6版本）推荐使用 _uid 作为排序字段和全局唯一值（注：不同版本的ES，官方文档有变动，请参考对应版本的文档。比如，7.x版本建议拷贝_id字段值到另外一个支持doc value的字段，用于作为排序字段）；2. 通过实时cursor来规避耗时和占存储的性能问题，基于上一页的结果帮助检索下一页；3. 使用search_after参数时，from的值必须为0或者-1● 需要排序；● 不适合跳页需求注：在7.x官方文档中，已不太建议使用Scroll API来深分页了.x/paginate-search-results.html#scroll-search-results
Java代码示例 ES 5.6.8版本 maven引用 <dependency><groupId>org.elasticsearch</groupId><artifactId>elasticsearch</artifactId><version>5.6.8</version></dependency><dependency><groupId>org.elasticsearch.client</groupId><artifactId>transport</artifactId><version>5.6.8</version></dependency> Search After 的Java代码示例 import org.elasticsearch.action.search.SearchRequestBuilder;import org.elasticsearch.action.search.SearchResponse;import org.elasticsearch.client.transport.TransportClient;import org.elasticsearch.common.settings.Settings;import org.elasticsearch.common.transport.InetSocketTransportAddress;import org.elasticsearch.index.query.QueryBuilders;import org.elasticsearch.search.SearchHit;import org.elasticsearch.search.sort.SortOrder;import org.elasticsearch.transport.client.PreBuiltTransportClient;import java.net.InetAddress;import java.net.UnknownHostException;import java.util.function.Consumer;public class EsSearchAfterHandler { private static final String UID = "_uid"; public static void main(String[] args) throws UnknownHostException { // example: 127.0.0.1 String esIp = "your es ip"; TransportClient esClient = buildEsTransportClient("elasticsearch", esIp, 9301); int batchSize = 1000; SearchRequestBuilder searchRequestBuilder = esClient.prepareSearch("your index") .setQuery(QueryBuilders.matchAllQuery()) .setSize(batchSize); EsSearchAfterHandler.searchForHit(searchRequestBuilder, searchHit -> { // your code ... // example: System.out.println(searchHit.getSourceAsString()); }); } /** * Search for hit. * * @param requestBuilder the request builder * @param consumer the consumer */ public static void searchForHit(SearchRequestBuilder requestBuilder, Consumer<SearchHit> consumer) { searchForResponse(requestBuilder, searchResponse -> { SearchHit[] searchHits = searchResponse.getHits().getHits(); for (SearchHit searchHit : searchHits) { consumer.accept(searchHit); } }); } /** * Search for response. * * @param requestBuilder the request builder * @param consumer the consumer */ public static void searchForResponse(SearchRequestBuilder requestBuilder, Consumer<SearchResponse> consumer) { if (requestBuilder == null || consumer == null) { return; } //requestBuilder.setSize(100); //在构建查询条件时，即可设置大小 //设置排序字段 SearchRequestBuilder sortBuilder = requestBuilder.addSort(UID, SortOrder.ASC); SearchResponse searchResponse = sortBuilder.get(); SearchHit[] searchHits = searchResponse.getHits().getHits(); while (searchHits.length > 0) { consumer.accept(searchResponse); SearchHit last = searchHits[searchHits.length - 1]; sortBuilder = sortBuilder.searchAfter(last.getSortValues()); searchResponse = sortBuilder.get(); searchHits = searchResponse.getHits().getHits(); } } private static TransportClient buildEsTransportClient(String esCluster, String esIp, Integer esPort) throws UnknownHostException { Settings esSettings = Settings.builder() .put("cluster.name", esCluster) .build(); return new PreBuiltTransportClient(esSettings) .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName(esIp), esPort)); }} ES 7.9.2版本 maven引用 <dependency> <groupId>org.elasticsearch</groupId> <artifactId>elasticsearch</artifactId> <version>7.9.2</version> </dependency> <dependency> <groupId>org.elasticsearch.client</groupId> <artifactId>elasticsearch-rest-high-level-client</artifactId> <version>7.9.2</version> </dependency> Search After 的Java代码示例 /** * ES Search After查询 * * @author zuozhu.meng **/public class EsSearchAfterHandler { private static final String UID = "_id"; /** * Search for hit. * * @param searchRequest the search request * @param consumer the consumer */ public static void searchForHit(RestHighLevelClient client, SearchRequest searchRequest, Consumer<SearchHit> consumer) throws IOException { searchForResponse(client, searchRequest, searchResponse -> forEachHits(searchResponse, consumer)); } /** * Search for response. * * @param searchRequest the search request * @param consumer the consumer */ public static void searchForResponse(RestHighLevelClient client, SearchRequest searchRequest, Consumer<SearchResponse> consumer) throws IOException { if (searchRequest == null || consumer == null) { return; } SearchSourceBuilder sourceBuilder = searchRequest.source(); // sourceBuilder.size(100); //在构建查询条件时，即可设置大小 //设置排序字段 sourceBuilder.sort(UID, SortOrder.ASC); SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT); SearchHit[] searchHits = searchResponse.getHits().getHits(); while (searchHits.length > 0) { consumer.accept(searchResponse); SearchHit last = searchHits[searchHits.length - 1]; sourceBuilder.searchAfter(last.getSortValues()); searchResponse = client.search(searchRequest, RequestOptions.DEFAULT); searchHits = searchResponse.getHits().getHits(); } } public static void forEachHits(SearchResponse searchResponse, Consumer<SearchHit> consumer) { if (searchResponse == null) { return; } SearchHit[] searchHits = searchResponse.getHits().getHits(); for (SearchHit searchHit : searchHits) { consumer.accept(searchHit); } } }Elasticsearch-Search After分页-Java示例