根据ID Java流将数据合并在一起

Question

我目前有一组数据，我从我的Java应用程序中的API中撤回。返回的数据如下：

    $(document).ready(function() {
    $('form').submit(function(e) {
        var isValid = true;
        var allow = false;
        $('input[type="text"]').each(function() {
            if ($.trim($(this).val()) == '') {
                isValid = false;
                $(this).css({
                    "border": "1px solid red",
                    "background": "#FFCECE"
                });                 
            }
            else {
                $(this).css({
                    "border": "",
                    "background": ""
                });
            }
        });
        if (isValid == false){ 
            if(!confirm('Few Fields are empty! Are you sure want to continue?')){
                e.preventDefault();
          } else {
          alert('Thank you for submitting');
          }            
        }
        else 
           alert('Thank you for submitting');
        });
});

正如您所看到的，{ "id": 1, "receiptId": "123456", "selections": [ { "name": "Apple", "price": "£1" } ] }, { "id": 2, "receiptId": "678910", "selections": [ { "name": "Pear", "price": "£0.5" } ] }, { "id": 3, "receiptId": "123456", "selections": [ { "name": "Banana", "price:": "£2.00" } ] } 中的两个是相同的，我想将任何重复的receiptId数据合并为一个块。即：

receiptId's

目前，我只是通过执行以下操作将数据流式传输到地图中：

{
  "id": 1,
  "receiptId": "123456",
  "selections": [
    {
      "name": "Apple",
      "price": "£1"
    },
    {
      "name": "Banana",
      "price": "£2.00"
    }
  ]
},
{
  "id": 2,
  "receiptId": "678910",
  "selections": [
    {
      "name": "Pear",
      "price": "£0.5"
    }
  ]
},

List<String> data = data.getData() .stream() .map(this::dataToReadable) .collect(Collectors.toList()); 执行以下操作：

dataToReadable

private String dataToReadable(List data) { return new DataBuilder().fromData(data) .buildData(); } 执行以下操作：

fromData

Answer 1

看看这是否有效。

 data.getData()
        .stream()
        .collect(Collectors.groupingBy(Data::getRecieptId))
        .entrySet()
        .stream()
        .map(item -> dataToReadable(item.getValue()))
        .collect(Collectors.toList());