elasticsearch FunctionScore Java API sample

public Response> fieldValueFactor(String query) {
        // query
        MultiMatchQueryBuilder multiMatchQueryBuilder = new MultiMatchQueryBuilder(query)
                .field(Constants.TITLE).field(Constants.SUMMARY);
        // fieldValueFactor
        FieldValueFactorFunctionBuilder fieldValueFactor = ScoreFunctionBuilders.fieldValueFactorFunction(Constants.NUM_REVIEWS)
                .factor(2).modifier(FieldValueFactorFunction.Modifier.LOG1P);
        // functionscore
        FunctionScoreQueryBuilder queryBuilder = QueryBuilders.functionScoreQuery(multiMatchQueryBuilder, fieldValueFactor);

        SearchRequestBuilder requestBuilder = client.prepareSearch(bookIndex).setTypes(bookType)
                .setQuery(queryBuilder).setFetchSource(Constants.fetchFieldsTSPN, null);
    }

script_score，通过脚本进行自定义打分

        // 参数
        Map params = new HashMap<>();
        params.put("threshold", threshold);
        //painless 脚本，注意不能换行
        String scriptStr = "publish_date = doc['publish_date'].value; num_reviews = doc['num_reviews'].value; if (publish_date > Date.parse('yyyy-MM-dd', threshold).getTime()) { return log(2.5 + num_reviews) }; return log(1 + num_reviews);";
        script script = new script(scriptType.INLINE, "painless", scriptStr, params);

        //构造脚本查询对象
        scriptScoreFunctionBuilder scriptScoreFunctionBuilder = ScoreFunctionBuilders.scriptFunction(script);

        //组合成完整查询
        FunctionScoreQueryBuilder queryBuilder = QueryBuilders.functionScoreQuery(multiMatchQueryBuilder, scriptScoreFunctionBuilder);