本文要实现的一个功能，根据品牌、分类、规格、价格过滤查询商品的功能，并对查询结果的关键字进行高亮显示。只做后端功能。

本文是以代码驱动，如果看不太懂，可以先复制代码，再慢慢看，注释很详细。

1、引入相关依赖

主要就是fastjson和spring-boot-starter-data-elasticsearch(SpringBoot项目)，fastJson的作用是转换对象使用，当然也可以进行时间格式化（本文未作处理）。

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-data-elasticsearch</artifactId>
</dependency>
<dependency>
	<groupId>com.alibaba</groupId>
	<artifactId>fastjson</artifactId>
	<version>1.2.28</version>
</dependency>

2、ElasticSearch数据测试准备

①创建Goods类，测试类里注入相关对象

@Document(indexName = "goods_sku",type = "goods")
@Data
public class Goods {
    @Id
    @Field(type = FieldType.Long,store = true)
    private Long id;            // 主键Id
    @Field(type = FieldType.Text,analyzer = "ik_smart",store = true)
    private String name;        // 商品名称
    @Field(type = FieldType.Integer,store = true)
    private Integer price;      // 商品价格
    @Field(type = FieldType.Text,store = true,index = false)
    private String image;       // 商品图片src
    @Field(type = FieldType.Date,store = true,index = false)
    private Date createTime;    // 商品创建时间
    @Field(type = FieldType.Long,store = true,index = false)
    private Long spuId;         // Spu的Id
    @Field(type = FieldType.Keyword,store = true)
    private String categoryName;// 分类名称
    @Field(type = FieldType.Keyword,store = true)
    private String brandName;   // 品牌名称
    @Field(type = FieldType.Object,store = true)
    private Map spec;           // 规格Map Map<String,String>，如<"颜色","黑色">
    @Field(type = FieldType.Integer,store = true,index = false)
    private Integer saleNum;    // 销量

    public Goods(){

    }

    public Goods(Long id, String name, Integer price, String image, Date createTime, Long spuId, String categoryName, String brandName, Map spec, Integer saleNum) {
        this.id = id;
        this.name = name;
        this.price = price;
        this.image = image;
        this.createTime = createTime;
        this.spuId = spuId;
        this.categoryName = categoryName;
        this.brandName = brandName;
        this.spec = spec;
        this.saleNum = saleNum;
    }
}

@Autowired
private ElasticsearchTemplate template;
@Autowired
private GoodsRepository goodsRepository;
@Autowired
private EsResultMapper esResultMapper;

②数据准备 - 尽量多准备一些数据，方便测试查询

@Test
public void createIndex(){
	template.createIndex(Goods.class);
}

@Test
public void createDoc(){
	Map map1 = new HashMap();
	map1.put("颜色","紫色");
	map1.put("套餐","标准套餐");
	Goods goods1 = new Goods(7L,"小米 Mini9秘境黑优惠套餐16G+64G",100,"xxxx",new Date(),2L,"手机","小米",map1,100);
	goodsRepository.save(goods1);
	// 使用saveAll批量存储
}

3、构建基本查询方法

该方法通过传过来的条件Map，根据条件进行过滤查询，比如分类、品牌、规格、价格区间等(具体取决于需求)。

/**
 * 构建基本查询 - 搜索关键字、分类、品牌、规格、价格
 * @param searchMap
 * @return
 */
private BoolQueryBuilder buildBasicQuery(Map searchMap) {
	// 构建布尔查询
	BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
	// 关键字查询
	boolQueryBuilder.must(QueryBuilders.matchQuery("name",searchMap.get("keywords")));
	// 分类、品牌、规格 都是需要精准查询的，无需分词
	// 商品分类过滤
	if (searchMap.get("category") != null){
		boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("categoryName",searchMap.get("category")));
	}
	// 商品品牌过滤
	if(searchMap.get("brand") != null){
		boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("brandName",searchMap.get("brand")));
	}
	// 规格过滤
	if(searchMap.get("spec") != null){
		Map<String,String> map = (Map) searchMap.get("spec");
		for(Map.Entry<String,String> entry : map.entrySet()){
			// 规格查询[spec.xxx],因为规格是不确定的，所以需要精确查找，加上.keyword，如spec.颜色.keyword
			boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("spec." + entry.getKey() + ".keyword",entry.getValue()));
		}
	}
	// 价格过滤
	if(searchMap.get("price") != null){
		// 价格： 0-500  0-*
		String[] prices = ((String)searchMap.get("price")).split("-");
		if(!prices[0].equals("0")){  // 加两个0是，因为价格转换成分
			boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").gt(prices[0] + "00"));
		}
		if(!prices[1].equals("*")){  // 价格有上限
			boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").lt(prices[1] + "00"));
		}
	}
	return boolQueryBuilder;
}

4、查询分类列表

主要是根据搜索关键字查询查询出来的结果，将其分类，然后把分类查询出来，显示到前端。

/**
 * 查询分类列表
 * @param searchMap
 * @return
 */
private List<String> searchCategoryList(Map searchMap) {
	NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
	// 构建查询
	BoolQueryBuilder boolQueryBuilder = buildBasicQuery(searchMap);
	nativeSearchQueryBuilder.withQuery(boolQueryBuilder);
	// 分类聚合名
	String groupName = "sku_category";
	// 构建聚合查询
	TermsAggregationBuilder termsAggregationBuilder = AggregationBuilders.terms(groupName).field("categoryName");
	nativeSearchQueryBuilder.addAggregation(termsAggregationBuilder);
	// 获取聚合分页结果
	AggregatedPage<Goods> goodsList = (AggregatedPage<Goods>) goodsRepository.search(nativeSearchQueryBuilder.build());
	// 在查询结果中找到聚合 - 根据聚合名称
	StringTerms stringTerms = (StringTerms) goodsList.getAggregation(groupName);
	// 获取桶
	List<StringTerms.Bucket> buckets = stringTerms.getBuckets();
	// 使用流Stream 将分类名存入集合
	List<String> categoryList = buckets.stream().map(bucket -> bucket.getKeyAsString()).collect(Collectors.toList());
	// 打印分类名称
	categoryList.forEach(System.out::println);
	return categoryList;
}

既然有了分类，那么肯定还有对应的品牌、规格。其实品牌和规格与分类是有一个联系的。ElasticSearch查询出分类，每个分类对应一个id，也就是说所有分类和分类的id应该存到Redis中去，这样前端就可以根据返回的分类集合去查询对应的品牌和规格，这里只是提供一个实现思路。

String categoryName = "";       // 分类名
if(searchMap.get("category") == null){  // 如果查询条件没有分类
	// 默认取分类列表的第一个
	if(categoryList.size() > 0){
		categoryName = categoryList.get(0);
	}
}else{      // 如果查询条件有分类
	// 则取查询条件中的分类
	categoryName = searchMap.get("category");
}

// 根据分类名查询品牌 - 实际应该从Redis中查询
if(searchMap.get("brand")==null) {
	List<Map> brandList = brandDao.findListByCategoryName(categoryName);
	resultMap.put("brandList", brandList);
}

// 根据分类查询规格 - 实际应该从Redis中查询
List<Map> specList = specDao.findListByCategoryName(categoryName);
for(Map spec:specList){
	// 规格选项列表 - 选项与选项之间是以,（逗号）分隔的
	String[] options = ((String) spec.get("options")).split(",");
	// 讲过规格选项放入到规格对象中
	spec.put("options",options);
}
// 将规格对象放入到结果集
resultMap.put("specList",specList);

5、重新实现SearchResultMapper - 高亮前奏

因为默认的SearchResultMapper是没有高亮的，我们需要重新实现，重写AggregatedPage方法。

@Component
public class EsResultMapper implements SearchResultMapper {

    @Override
    public <T> AggregatedPage<T> mapResults(SearchResponse response, Class<T> aClass, Pageable pageable) {
        // 记录总条数
        long totalHits = response.getHits().getTotalHits();
        // 记录列表(泛型) - 构建Aggregate使用
        List<T> list = Lists.newArrayList();
        // 获取搜索结果(真正的的记录)
        SearchHits hits = response.getHits();
        for (SearchHit hit : hits) {
            if(hits.getHits().length <= 0){
                return null;
            }
            // 将原本的JSON对象转换成Map对象
            Map<String, Object> map = hit.getSourceAsMap();
            // 获取高亮的字段Map
            Map<String, HighlightField> highlightFields = hit.getHighlightFields();
            for (Map.Entry<String, HighlightField> highlightField : highlightFields.entrySet()) {
                // 获取高亮的Key
                String key = highlightField.getKey();
                // 获取高亮的Value
                HighlightField value = highlightField.getValue();
                // 实际fragments[0]就是高亮的结果，无需遍历拼接
                Text[] fragments = value.getFragments();
                StringBuilder sb = new StringBuilder();
                for (Text text : fragments) {
                    sb.append(text);
                }
                // 因为高亮的字段必然存在于Map中，就是key值
                // 可能有一种情况，就是高亮的字段是嵌套Map，也就是说在Map里面还有Map的这种情况，这里没有考虑
                map.put(key, sb.toString());
            }
            // 把Map转换成对象
            T item = JSON.parseObject(JSONObject.toJSONString(map),aClass);
            list.add(item);
        }
        // 返回的是带分页的结果
        return new AggregatedPageImpl<>(list, pageable, totalHits);
    }

}

6、查询商品(sku)列表

/**
 * 查询Sku集合 - 商品列表
 * @param searchMap 查询条件
 * @return
 */
private Map searchSkuList(Map searchMap) {
	Map resultMap = new HashMap();
	NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
	BoolQueryBuilder boolQueryBuilder = buildBasicQuery(searchMap);
	// 查询
	nativeSearchQueryBuilder.withQuery(boolQueryBuilder);
	// 排序
	String sortField = (String)searchMap.get("sortField");      // 排序字段
	String sortRule = (String)searchMap.get("sortRule");        // 排序规则 - 顺序(ASC)/倒序(DESC)
	if(sortField!= null && !"".equals(sortField)){
		nativeSearchQueryBuilder.withSort(SortBuilders.fieldSort(sortField).order(SortOrder.valueOf(sortRule)));
	}
	// 构建分页
	nativeSearchQueryBuilder.withPageable(PageRequest.of(0,15));

	// 构建高亮查询
	HighlightBuilder.Field field = new HighlightBuilder.Field("name").preTags("<font style='color:red'>").postTags("</font>");
	nativeSearchQueryBuilder.withHighlightFields(field);  // 名字高亮
	NativeSearchQuery build = nativeSearchQueryBuilder.build();
	// 获取查询结果
	AggregatedPage<Goods> goodsPage = template.queryForPage(build, Goods.class, esResultMapper);
	long total = goodsPage.getTotalElements();  // 总数据量
	long totalPage = goodsPage.getTotalPages(); // 总页数
	// ...你还要将是否有上页下页等内容传过去
	List<Goods> goodsList = goodsPage.getContent();
	goodsList.forEach(System.out::println);
	resultMap.put("rows",goodsList);
	resultMap.put("total",total);
	resultMap.put("totalPage",totalPage);
	return resultMap;
}

7、查询

/**
 * 搜索方法 - searchMap应该由前端传过来
 * searchMap里封装了一些条件，根据条件进行过滤
 */
@Test
public void search(){
	// 搜索条件Map
	Map searchMap = new HashMap();
	searchMap.put("keywords","小米");
//        searchMap.put("category","手机");
//        searchMap.put("brand","小米");
	Map map = new HashMap();
	map.put("颜色","紫色");
//        map.put("","");   // 其他规格类型
	searchMap.put("spec",map);
//        searchMap.put("price","0-3000");

	// 返回结果Map
	Map resultMap = new HashMap();
	// 查询商品列表
	resultMap.putAll(searchSkuList(searchMap));
	// 查询分类列表
	List<String> categoryList = searchCategoryList(searchMap);
	resultMap.put("categoryList",categoryList);
}

测试类完整代码

@RunWith(SpringRunner.class)
@SpringBootTest
public class GoodsTest {

    @Autowired
    private ElasticsearchTemplate template;
    @Autowired
    private GoodsRepository goodsRepository;
    @Autowired
    private EsResultMapper esResultMapper;

    @Test
    public void createIndex(){
        template.createIndex(Goods.class);
    }

    @Test
    public void createDoc(){
//        Map map1 = new HashMap();
//        map1.put("颜色","蓝色");
//        map1.put("套餐","标准套餐");
//        Goods goods1 = new Goods(2L,"Redmi Note7秘境黑优惠套餐16G+64G",100,"xxxx",new Date(),2L,"手机","小米",map1,100);
//
//        Map map2 = new HashMap();
//        map2.put("颜色","蓝色");
//        map2.put("套餐","标准套餐");
//        Goods goods2 = new Goods(3L,"Redmi Note7秘境黑优惠套餐16G+64G",500,"xxxx",new Date(),3L,"手机","小米",map2,100);
//
//        Map map3 = new HashMap();
//        map3.put("颜色","黑色");
//        map3.put("尺寸","64寸");
//        Goods goods3 = new Goods(4L,"小米电视 黑色 64寸 优惠套餐",1000,"xxxx",new Date(),4L,"电视","小米",map3,100);
//
//        Map map4 = new HashMap();
//        map4.put("颜色","金色");
//        map4.put("尺寸","46寸");
//        Goods goods4 = new Goods(5L,"华为电视 金色 46寸 优惠套餐",1500,"xxxx",new Date(),5L,"电视","华为",map4,100);
//
//        Map map5 = new HashMap();
//        map5.put("颜色","白金色");
//        map5.put("网络制式","全网通5G");
//        Goods goods5 = new Goods(6L,"华为P30 金色 全网通5G 优惠套餐",2000,"xxxx",new Date(),6L,"手机","华为",map5,100);
//        List<Goods> list = new ArrayList<>();
//        list.add(goods1);
//        list.add(goods2);
//        list.add(goods3);
//        list.add(goods4);
//        list.add(goods5);
//        goodsRepository.saveAll(list);
        Map map1 = new HashMap();
        map1.put("颜色","紫色");
        map1.put("套餐","标准套餐");
        Goods goods1 = new Goods(7L,"小米 Mini9秘境黑优惠套餐16G+64G",100,"xxxx",new Date(),2L,"手机","小米",map1,100);
        goodsRepository.save(goods1);
//                Map map1 = new HashMap();
//        map1.put("颜色","蓝色");
//        map1.put("套餐","标准套餐");
//        Goods goods1 = new Goods(2L,"Redmi Note7秘境黑优惠套餐16G+64G",100,"xxxx",new Date(),2L,"手机","小米",map1,100);
//        goodsRepository.save(goods1);
    }


    /**
     * 搜索方法 - searchMap应该由前端传过来
     * searchMap里封装了一些条件，根据条件进行过滤
     */
    @Test
    public void search(){
        // 搜索条件Map
        Map searchMap = new HashMap();
        searchMap.put("keywords","小米");
//        searchMap.put("category","手机");
//        searchMap.put("brand","小米");
        Map map = new HashMap();
        map.put("颜色","紫色");
//        map.put("","");   // 其他规格类型
        searchMap.put("spec",map);
//        searchMap.put("price","0-3000");

        // 返回结果Map
        Map resultMap = new HashMap();
        // 查询商品列表
        resultMap.putAll(searchSkuList(searchMap));
        // 查询分类列表
        List<String> categoryList = searchCategoryList(searchMap);
        resultMap.put("categoryList",categoryList);
    }

    /**
     * 查询Sku集合 - 商品列表
     * @param searchMap 查询条件
     * @return
     */
    private Map searchSkuList(Map searchMap) {
        Map resultMap = new HashMap();
        NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
        BoolQueryBuilder boolQueryBuilder = buildBasicQuery(searchMap);
        // 查询
        nativeSearchQueryBuilder.withQuery(boolQueryBuilder);
        // 排序
        String sortField = (String)searchMap.get("sortField");      // 排序字段
        String sortRule = (String)searchMap.get("sortRule");        // 排序规则 - 顺序(ASC)/倒序(DESC)
        if(sortField!= null && !"".equals(sortField)){
            nativeSearchQueryBuilder.withSort(SortBuilders.fieldSort(sortField).order(SortOrder.valueOf(sortRule)));
        }
        // 构建分页
        nativeSearchQueryBuilder.withPageable(PageRequest.of(0,15));

        // 构建高亮查询
        HighlightBuilder.Field field = new HighlightBuilder.Field("name").preTags("<font style='color:red'>").postTags("</font>");
        nativeSearchQueryBuilder.withHighlightFields(field);  // 名字高亮
        NativeSearchQuery build = nativeSearchQueryBuilder.build();
        // 获取查询结果
        AggregatedPage<Goods> goodsPage = template.queryForPage(build, Goods.class, esResultMapper);
        long total = goodsPage.getTotalElements();  // 总数据量
        long totalPage = goodsPage.getTotalPages(); // 总页数
        // ...你还要将是否有上页下页等内容传过去
        List<Goods> goodsList = goodsPage.getContent();
        goodsList.forEach(System.out::println);
        resultMap.put("rows",goodsList);
        resultMap.put("total",total);
        resultMap.put("totalPage",totalPage);
        return resultMap;
    }

    /**
     * 查询分类列表
     * @param searchMap
     * @return
     */
    private List<String> searchCategoryList(Map searchMap) {
        NativeSearchQueryBuilder nativeSearchQueryBuilder = new NativeSearchQueryBuilder();
        // 构建查询
        BoolQueryBuilder boolQueryBuilder = buildBasicQuery(searchMap);
        nativeSearchQueryBuilder.withQuery(boolQueryBuilder);
        // 分类聚合名
        String groupName = "sku_category";
        // 构建聚合查询
        TermsAggregationBuilder termsAggregationBuilder = AggregationBuilders.terms(groupName).field("categoryName");
        nativeSearchQueryBuilder.addAggregation(termsAggregationBuilder);
        // 获取聚合分页结果
        AggregatedPage<Goods> goodsList = (AggregatedPage<Goods>) goodsRepository.search(nativeSearchQueryBuilder.build());
        // 在查询结果中找到聚合 - 根据聚合名称
        StringTerms stringTerms = (StringTerms) goodsList.getAggregation(groupName);
        // 获取桶
        List<StringTerms.Bucket> buckets = stringTerms.getBuckets();
        // 使用流Stream 将分类名存入集合
        List<String> categoryList = buckets.stream().map(bucket -> bucket.getKeyAsString()).collect(Collectors.toList());
        // 打印分类名称
        categoryList.forEach(System.out::println);
        return categoryList;
    }

    /**
     * 构建基本查询 - 搜索关键字、分类、品牌、规格、价格
     * @param searchMap
     * @return
     */
    private BoolQueryBuilder buildBasicQuery(Map searchMap) {
        // 构建布尔查询
        BoolQueryBuilder boolQueryBuilder = QueryBuilders.boolQuery();
        // 关键字查询
        boolQueryBuilder.must(QueryBuilders.matchQuery("name",searchMap.get("keywords")));
        // 分类、品牌、规格 都是需要精准查询的，无需分词
        // 商品分类过滤
        if (searchMap.get("category") != null){
            boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("categoryName",searchMap.get("category")));
        }
        // 商品品牌过滤
        if(searchMap.get("brand") != null){
            boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("brandName",searchMap.get("brand")));
        }
        // 规格过滤
        if(searchMap.get("spec") != null){
            Map<String,String> map = (Map) searchMap.get("spec");
            for(Map.Entry<String,String> entry : map.entrySet()){
                // 规格查询[spec.xxx],因为规格是不确定的，所以需要精确查找，加上.keyword，如spec.颜色.keyword
                boolQueryBuilder.filter(QueryBuilders.matchPhraseQuery("spec." + entry.getKey() + ".keyword",entry.getValue()));
            }
        }
        // 价格过滤
        if(searchMap.get("price") != null){
            // 价格： 0-500  0-*
            String[] prices = ((String)searchMap.get("price")).split("-");
            if(!prices[0].equals("0")){  // 加两个0是，因为价格转换成分
                boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").gt(prices[0] + "00"));
            }
            if(!prices[1].equals("*")){  // 价格有上限
                boolQueryBuilder.filter(QueryBuilders.rangeQuery("price").lt(prices[1] + "00"));
            }
        }
        return boolQueryBuilder;
    }
}