Java8 Stream流遍历 如何使用索引、数组转换对应字符串

//文献
https://blog.csdn.net/qq_2300688967/article/details/100111432


//TEST
public static Map handle(String str, int index) {

//      System.out.println(index);
//      System.out.println(str);
        Map<Integer, String> map = new HashMap<>();
        map.put(index, str);
        return map;
    }

    public static void main(String[] args) {
        HashMap map = new HashMap();
        List<String> list = new ArrayList<>();
        list.add("微信");
        list.add("支付宝");
        map.put("data", list);
//      System.out.println(map);
        String biz_params = JSON.toJSONString(map);
        JSONObject jsonObject = JSONObject.parseObject(biz_params);
        JSONArray data = jsonObject.getJSONArray("data");
        StringBuilder result = new StringBuilder();
        data.stream().forEach( (item) -> {
            result.append(item);
            result.append(StrUtil.C_COMMA);
        });
        String substring = result.substring(0, result.length() - 1);

        System.out.println(result.toString());//微信,支付宝,
        System.out.println(substring);// 微信,支付宝
//      List list2 = IntStream.range(0, data.size()).mapToObj(i -> handle(list.get(i), i)).collect(Collectors.toList());

//      list2.stream().forEach( item -> {
//          JSONObject jsonObject1 = JSONObject.parseObject(item.toString());
//
////            jsonObject1.get)

////            result.append(item);
//          result.append(StrUtil.C_COMMA);
//      });
//      System.out.println(result);





    }

// USED

  //交易明细
        JSONObject target = JSONObject.parseObject(bizContent);
        JSONArray data = target.getJSONArray("data");
        StringBuilder payTypeResult = new StringBuilder();
        if (CollUtil.isNotEmpty(data)) {
            boolean flag = false;
            for (int i = 0; i < data.size(); i++) {
                JSONObject parse = data.getJSONObject(i);
                if (flag) {
                    payTypeResult.append(StrUtil.C_COMMA);
                }
                String payWay = PayWayEnum.RES_CODE_MAP.get(parse.getString("pay_type"));
                if (StrUtil.isNotEmpty(payWay)) {
                    payTypeResult.append(payWay);
                    flag = true;
                }
            }
        }
        String substring = payTypeResult.substring(0, payTypeResult.length - 1);