elasticsearch7.4.2 使用java API导出全量数据到文件

pom.xml:

<dependency>
    <groupId>org.elasticsearch.client</groupId>
    <artifactId>elasticsearch-rest-high-level-client</artifactId>
    <version>7.4.2</version>
</dependency>

java代码:

public static boolean getEs(String beginDate, String endDate) throws IOException {
        RestHighLevelClient client = new RestHighLevelClient(RestClient.builder(new HttpHost("192.168.100.100", 9201, "http")));
        //设定滚动时间间隔
        final Scroll scroll = new Scroll(TimeValue.timeValueMinutes(1L));
        SearchRequest searchRequest = new SearchRequest("index");//索引库
        searchRequest.types("type");//索引表
        searchRequest.scroll(scroll);
        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
        //设定每次返回多少条数据
        searchSourceBuilder.size(pageNum);
        //返回字段信息
        searchSourceBuilder.fetchSource(new String[]{"id", "x_dip","i_dport"}, new String[]{});

        //x_begintime 字段范围值过滤
        RangeQueryBuilder rangeQueryBuilder = QueryBuilders.rangeQuery("x_begintime");
        rangeQueryBuilder.gte(beginDate);//开始时间
        rangeQueryBuilder.lte(endDate);//结束时间
        BoolQueryBuilder boolBuilder = QueryBuilders.boolQuery();
        boolBuilder.must(rangeQueryBuilder);
        searchSourceBuilder.query(boolBuilder);
        searchRequest.source(searchSourceBuilder);

        SearchResponse searchResponse = client.search(searchRequest, RequestOptions.DEFAULT);
        String scrollId = searchResponse.getScrollId();
        SearchHit[] searchHits = searchResponse.getHits().getHits();
        //把导出的结果以JSON的格式写到文件里,filePath=写入文件路径
        BufferedWriter out = new BufferedWriter(new FileWriter(filePath, true));
        
        System.out.println("-----"+searchHits.length+"-----");
        for (SearchHit searchHit : searchHits) {
            String json = searchHit.getSourceAsString();
            System.out.println(json);
            out.write(json);
            out.write("
");
        }
        //遍历搜索命中的数据，直到没有数据
        while (searchHits != null && searchHits.length > 0) {
            SearchScrollRequest scrollRequest = new SearchScrollRequest(scrollId);
            scrollRequest.scroll(scroll);
            searchResponse = client.scroll(scrollRequest, RequestOptions.DEFAULT);
            scrollId = searchResponse.getScrollId();
            searchHits = searchResponse.getHits().getHits();
            if (searchHits != null && searchHits.length > 0) {
                System.out.println("-----"+searchHits.length+"-----");
                for (SearchHit searchHit : searchHits) {
                    String json = searchHit.getSourceAsString();
                    System.out.println(json);
                    out.write(json);
                    out.write("
");
                }
            }
        }

        //清除滚屏
        ClearScrollRequest clearScrollRequest = new ClearScrollRequest();
        //也可以选择setScrollIds()将多个scrollId一起使用
        clearScrollRequest.addScrollId(scrollId);
        ClearScrollResponse clearScrollResponse = null;
        try {
            clearScrollResponse = client.clearScroll(clearScrollRequest,RequestOptions.DEFAULT);
        } catch (IOException e) {
            e.printStackTrace();
        }
        boolean succeeded = clearScrollResponse.isSucceeded();
        if(succeeded){
            System.out.println(filePath);
        }
        out.close();
        client.close();
        //成功返回true
        return succeeded;
    }