map資料按照list排序
阿新 • • 發佈：2020-07-20
簡介 （Introduction）：
背景
需要對欄位進行排序,但是,一個欄位的結果存在一個map中,一個存在list中,需要讓map的陣列,按照list的順序進行排序結構圖
list順序
[
{
"fieldKey":"關鍵字",
"alias":"ID",
"owner":"mysql",
"field":"ID",
"fieldNumber":1
},
{
"fieldKey":"名稱",
"alias":"CHNAME",
"owner":"mysql","field":"NAME",
"fieldNumber":2
},
{
"fieldKey":"是否刪除",
"alias":"DELETED",
"owner":"mysql",
"field":"ISDELETED",
"fieldNumber":3
},
{
"fieldKey":"序號",
"alias":"ORDERNO",
"owner":"mysql",
"field":"ORDERNO","fieldNumber":4
}
]map順序
{
"ORDERNO":{
"fieldKey":"序號",
"alias":"ORDERNO",
"owner":"mysql",
"field":"ORDERNO",
"fieldNumber":4
},
"NAME":{
"fieldKey":"名稱",
"alias":"CHNAME",
"owner":"mysql",
"field":"NAME","fieldNumber":2
},
"ISDELETED":{
"fieldKey":"是否刪除",
"alias":"DELETED",
"owner":"mysql",
"field":"ISDELETED",
"fieldNumber":3
},
"ID":{
"fieldKey":"關鍵字",
"alias":"ID",
"owner":"mysql",
"field":"ID",
"fieldNumber":1
}
}
核心
快速上手（Getting Started）
模型
list模型:
/**
* 生成資源陣列
*
* @return 結果集
*/
private static List<FieldDemo> getListSource() {
List<FieldDemo> fieldDemos = new ArrayList<>();
FieldDemo fieldDemo = new FieldDemo();
fieldDemo.setField("ID");
fieldDemo.setAlias("ID");
fieldDemo.setFieldKey("關鍵字");
fieldDemo.setOwner("mysql");
fieldDemo.setFieldNumber(1); FieldDemo fieldDemo2 = new FieldDemo();
fieldDemo2.setField("NAME");
fieldDemo2.setAlias("CHNAME");
fieldDemo2.setFieldKey("名稱");
fieldDemo2.setOwner("mysql");
fieldDemo2.setFieldNumber(2); FieldDemo fieldDemo3 = new FieldDemo();
fieldDemo3.setField("ISDELETED");
fieldDemo3.setAlias("DELETED");
fieldDemo3.setFieldKey("是否刪除");
fieldDemo3.setOwner("mysql");
fieldDemo3.setFieldNumber(3); FieldDemo fieldDemo4 = new FieldDemo();
fieldDemo4.setField("ORDERNO");
fieldDemo4.setAlias("ORDERNO");
fieldDemo4.setFieldKey("序號");
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結果集
*/
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("關鍵字");
fieldDemo.setOwner("mysql");
fieldDemo.setFieldNumber(1); FieldDemo fieldDemo2 = new FieldDemo();
fieldDemo2.setField("NAME");
fieldDemo2.setAlias("CHNAME");
fieldDemo2.setFieldKey("名稱");
fieldDemo2.setOwner("mysql");
fieldDemo2.setFieldNumber(2); FieldDemo fieldDemo3 = new FieldDemo();
fieldDemo3.setField("ISDELETED");
fieldDemo3.setAlias("DELETED");
fieldDemo3.setFieldKey("是否刪除");
fieldDemo3.setOwner("mysql");
fieldDemo3.setFieldNumber(3); FieldDemo fieldDemo4 = new FieldDemo();
fieldDemo4.setField("ORDERNO");
fieldDemo4.setAlias("ORDERNO");
fieldDemo4.setFieldKey("序號");
fieldDemo4.setOwner("mysql");
fieldDemo4.setFieldNumber(4); fieldDemos.add(fieldDemo4);
fieldDemos.add(fieldDemo3);
fieldDemos.add(fieldDemo);
fieldDemos.add(fieldDemo2);
return fieldDemos;
}
業務
核心處理
/**
* 讓複雜map按照list的順序排序
*
* @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())) {
// 生成中間儲存map,存入資料和對應的序號
middleMap.put(fieldDemoFieldDemoEntry.getKey(), fieldDemo.getFieldNumber());
}
}
} // 生成的結果集加入到list中
List<Map.Entry<FieldDemo, Integer>> entryList = new ArrayList(middleMap.entrySet()); // 根據value 進行排序
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());
}
}
}
}
測試
public static void main(String[] args) {
FieldDemo fieldDemo = new FieldDemo();
System.out.println("fieldDemo順序:" + new Gson().toJson(fieldDemo));
// 讓listSource2跟listSource順序一致
Map<FieldDemo, FieldDemo> mapSource = getMapSource();
System.out.println("map順序:" + new Gson().toJson(mapSource));
List<FieldDemo> listSource = getListSource();
System.out.println("list順序:" + new Gson().toJson(listSource));
// mapSource 跟 listSource順序一致,去除不是listSource理的欄位
Map<FieldDemo, FieldDemo> newMap = new HashMap<>();
sortMapFromList(listSource, mapSource, newMap);
System.out.println("排序後:" + newMap);
}
待開發中
環境設定 （Prerequisite）：
- 環境
JDK1.8 - 配置
IDEA 2019 存在問題
暫無
- 環境
進階篇 （Advanced）：
研究中 ......