es--elasticsearch--篇四：完成各个功能的接口，实现完整的文本搜索案例

先实现基本分页查询

@Service
public class HotelServiceImpl
        extends ServiceImpl
        implements HotelService {
 
    @Autowired
    private RestHighLevelClient client;//如果容器当中没有注入，需要在启动类中注入
 
    @Override//ctrl + alt + b
    public PageResult search(RequestParams params) {
        try {
            //request
            SearchRequest request = new SearchRequest("hotel");
            //dsl
            String key = params.getKey();
            if(key==null || "".equals(key)){
                //如果没有输如要搜索的内容，就全搜
                request.source().query(QueryBuilders.matchAllQuery());
            }else{
                request.source().query(QueryBuilders.matchQuery("all",key));
            }
            //分页
            int page = params.getPage();
            int size = params.getSize();
            request.source().from((page-1)*size).size(size);
            //发请求
            SearchResponse response = client.search(request, RequestOptions.DEFAULT);
            //处理结果
            PageResult pageResult = resHandler(response);
            return pageResult;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
 
    //处理响应结果的方法
    public PageResult resHandler(SearchResponse response){
        SearchHits searchHits = response.getHits();
        //total
        long total = searchHits.getTotalHits().value;
        System.out.println("total"+total);
        //文档数组在hits>hits中
        SearchHit[] hits = searchHits.getHits();
        List hotelDocList = new ArrayList<>();
        for (SearchHit hit : hits) {
            String hotelJson = hit.getSourceAsString();
            HotelDoc hotelDoc = JSON.parseObject(hotelJson, HotelDoc.class);
 
            //高亮相关
            Map highlightFields = hit.getHighlightFields();
            if(highlightFields != null