java实现Elasticsearch跳页查询

1. 首先，需要在Java项目中引入Elasticsearch的Java API依赖：

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.12.0</version>
</dependency>

2. 创建Elasticsearch客户端连接：

RestHighLevelClient client = new RestHighLevelClient(
        RestClient.builder(
                new HttpHost("localhost", 9200, "http")));

3. 创建查询请求：

SearchRequest searchRequest = new SearchRequest("index_name");
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.from(pageNumber * pageSize);
sourceBuilder.size(pageSize);
sourceBuilder.query(QueryBuilders.matchAllQuery());
searchRequest.source(sourceBuilder);

其中，`pageNumber`为要查询的页码，`pageSize`为每页的大小。

4. 执行查询请求：

SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);

5. 处理查询结果：

SearchHits hits = searchResponse.getHits();
for (SearchHit hit : hits) {
    // 处理查询结果
}

完整代码示例：

RestHighLevelClient client = new RestHighLevelClient(
        RestClient.builder(
                new HttpHost("localhost", 9200, "http")));

int pageNumber = 1;
int pageSize = 10;

SearchRequest searchRequest = new SearchRequest("index_name");
SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
sourceBuilder.from(pageNumber * pageSize);
sourceBuilder.size(pageSize);
sourceBuilder.query(QueryBuilders.matchAllQuery());
searchRequest.source(sourceBuilder);

SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);

SearchHits hits = searchResponse.getHits();
for (SearchHit hit : hits) {
    // 处理查询结果
}

client.close();