map数据按照list排序

• 简介 （Introduction）：

  • 背景
    需要对字段进行排序,但是,一个字段的结果存在一个map中,一个存在list中,需要让map的数组,按照list的顺序进行排序

  • 结构图
    list顺序

    

     [
         {
             "fieldKey":"关键字",
             "alias":"ID",
             "owner":"mysql",
             "field":"ID",
             "fieldNumber":1
         },
         {
             "fieldKey":"名称",
             "alias":"CHNAME",
             "owner":"mysql",
             "field":"NAME",
             "fieldNumber":2
         },
         {
             "fieldKey":"是否删除",
             "alias":"DELETED",
             "owner":"mysql",
             "field":"ISDELETED",
             "fieldNumber":3
         },
         {
             "fieldKey":"序号",
             "alias":"ORDERNO",
             "owner":"mysql",
             "field":"ORDERNO",
             "fieldNumber":4
         }
     ]

    map顺序

    

     {
         "ORDERNO":{
             "fieldKey":"序号",
             "alias":"ORDERNO",
             "owner":"mysql",
             "field":"ORDERNO",
             "fieldNumber":4
         },
         "NAME":{
             "fieldKey":"名称",
             "alias":"CHNAME",
             "owner":"mysql",
             "field":"NAME",
             "fieldNumber":2
         },
         "ISDELETED":{
             "fieldKey":"是否删除",
             "alias":"DELETED",
             "owner":"mysql",
             "field":"ISDELETED",
             "fieldNumber":3
         },
         "ID":{
             "fieldKey":"关键字",
             "alias":"ID",
             "owner":"mysql",
             "field":"ID",
             "fieldNumber":1
         }
     }

• 核心

• 快速上手（Getting Started）

模型

list模型:

 /**
      * 生成资源数组
      *
      * @return 结果集
      */
     private static List<FieldDemo> getListSource() {
         List<FieldDemo> fieldDemos = new ArrayList<>();
         FieldDemo fieldDemo = new FieldDemo();
         fieldDemo.setField("ID");
         fieldDemo.setAlias("ID");
         fieldDemo.setFieldKey("关键字");
         fieldDemo.setOwner("mysql");
         fieldDemo.setFieldNumber(1);

         FieldDemo fieldDemo2 = new FieldDemo();
         fieldDemo2.setField("NAME");
         fieldDemo2.setAlias("CHNAME");
         fieldDemo2.setFieldKey("名称");
         fieldDemo2.setOwner("mysql");
         fieldDemo2.setFieldNumber(2);

         FieldDemo fieldDemo3 = new FieldDemo();
         fieldDemo3.setField("ISDELETED");
         fieldDemo3.setAlias("DELETED");
         fieldDemo3.setFieldKey("是否删除");
         fieldDemo3.setOwner("mysql");
         fieldDemo3.setFieldNumber(3);

         FieldDemo fieldDemo4 = new FieldDemo();
         fieldDemo4.setField("ORDERNO");
         fieldDemo4.setAlias("ORDERNO");
         fieldDemo4.setFieldKey("序号");
         fieldDemo4.setOwner("mysql");
         fieldDemo4.setFieldNumber(4);

         fieldDemos.add(fieldDemo);
         fieldDemos.add(fieldDemo2);
         fieldDemos.add(fieldDemo3);
         fieldDemos.add(fieldDemo4);

         return fieldDemos;
     }

map模型:

 /**
      * 生成map
      *
      * @return map结果集
      */
     private static Map<FieldDemo, FieldDemo> getMapSource() {
         Map<FieldDemo, FieldDemo> map = new HashMap<>();
         List<FieldDemo> listSource = getListSource();
         List<FieldDemo> listSource2 = getListSource2();
         for (FieldDemo fieldDemo : listSource) {
             for (FieldDemo demo : listSource2) {
                 if (fieldDemo.getField().equalsIgnoreCase(demo.getField())) {
                     map.put(fieldDemo, demo);
                 }
             }
         }
         return map;
     }

     private static List<FieldDemo> getListSource2() {
         List<FieldDemo> fieldDemos = new ArrayList<>();
         FieldDemo fieldDemo = new FieldDemo();
         fieldDemo.setField("ID");
         fieldDemo.setAlias("ID");
         fieldDemo.setFieldKey("关键字");
         fieldDemo.setOwner("mysql");
         fieldDemo.setFieldNumber(1);

         FieldDemo fieldDemo2 = new FieldDemo();
         fieldDemo2.setField("NAME");
         fieldDemo2.setAlias("CHNAME");
         fieldDemo2.setFieldKey("名称");
         fieldDemo2.setOwner("mysql");
         fieldDemo2.setFieldNumber(2);

         FieldDemo fieldDemo3 = new FieldDemo();
         fieldDemo3.setField("ISDELETED");
         fieldDemo3.setAlias("DELETED");
         fieldDemo3.setFieldKey("是否删除");
         fieldDemo3.setOwner("mysql");
         fieldDemo3.setFieldNumber(3);

         FieldDemo fieldDemo4 = new FieldDemo();
         fieldDemo4.setField("ORDERNO");
         fieldDemo4.setAlias("ORDERNO");
         fieldDemo4.setFieldKey("序号");
         fieldDemo4.setOwner("mysql");
         fieldDemo4.setFieldNumber(4);

         fieldDemos.add(fieldDemo4);
         fieldDemos.add(fieldDemo3);
         fieldDemos.add(fieldDemo);
         fieldDemos.add(fieldDemo2);
         return fieldDemos;
     }

业务

核心处理

  /**
      * 让复杂map按照list的顺序排序
      *
      * @param list
      * @param map
      * @param newMap
      */
     public static void sortMapFromList(List<FieldDemo> list, Map<FieldDemo, FieldDemo> map, Map<FieldDemo, FieldDemo> newMap) {

         Map<FieldDemo, Integer> middleMap = new HashMap<>(16);

         for (FieldDemo fieldDemo : list) {
             for (Map.Entry<FieldDemo, FieldDemo> fieldDemoFieldDemoEntry : map.entrySet()) {
                 String field = fieldDemoFieldDemoEntry.getKey().getField();

                 if (field.equalsIgnoreCase(fieldDemo.getField())) {
                     // 生成中间存储map,存入数据和对应的序号
                     middleMap.put(fieldDemoFieldDemoEntry.getKey(), fieldDemo.getFieldNumber());
                 }
             }
         }

         // 生成的结果集加入到list中
         List<Map.Entry<FieldDemo, Integer>> entryList = new ArrayList(middleMap.entrySet());

         // 根据value 进行排序
         Collections.sort(entryList, new Comparator<Map.Entry<FieldDemo, Integer>>() {
             @Override
             public int compare(Map.Entry<FieldDemo, Integer> o1, Map.Entry<FieldDemo, Integer> o2) {
                 return o1.getValue().compareTo(o2.getValue());
             }
         });

         System.out.println("entryList:" + new Gson().toJson(entryList));

         for (Map.Entry<FieldDemo, Integer> fieldDemoFieldDemoEntry : entryList) {

             for (Map.Entry<FieldDemo, FieldDemo> demoFieldDemoEntry : map.entrySet()) {

                 String field = demoFieldDemoEntry.getKey().getField();

                 if (field.equalsIgnoreCase(fieldDemoFieldDemoEntry.getKey().getField())) {

                     System.out.println("fieldNumber:" + new Gson().toJson(fieldDemoFieldDemoEntry.getValue()));
                     System.out.println("fieldDemoFieldDemoEntry:" + new Gson().toJson(fieldDemoFieldDemoEntry.getKey()));
                     System.out.println("demoFieldDemoEntry:" + new Gson().toJson(demoFieldDemoEntry.getValue()));

                     newMap.put(fieldDemoFieldDemoEntry.getKey(), demoFieldDemoEntry.getValue());
                 }
             }
         }
     }

测试

 public static void main(String[] args) {

         FieldDemo fieldDemo = new FieldDemo();

         System.out.println("fieldDemo顺序:" + new Gson().toJson(fieldDemo));

         // 让listSource2跟listSource顺序一致
         Map<FieldDemo, FieldDemo> mapSource = getMapSource();

         System.out.println("map顺序:" + new Gson().toJson(mapSource));

         List<FieldDemo> listSource = getListSource();

         System.out.println("list顺序:" + new Gson().toJson(listSource));

         // mapSource 跟 listSource顺序一致,去除不是listSource理的字段
         Map<FieldDemo, FieldDemo> newMap = new HashMap<>();

         sortMapFromList(listSource, mapSource, newMap);

         System.out.println("排序后:" + newMap);
     }

待开发中

• 环境设置 （Prerequisite）：

  • 环境
    JDK1.8
  • 配置
    
    IDEA 2019

  • 存在问题
    
    暂无

• 进阶篇 （Advanced）：

  研究中 ......