java递归菜单树转换成json字符串

时间:2021-02-25 12:37:39
package com.cjonline.foundation.member.util;

import java.util.ArrayList;
import java.util.List;

public class Tree {
 private static List<Person> dataSource=new ArrayList<Person>();
 static{
  Person p1 = new Person("1000","",1);
  Person p2 = new Person("1001","1000",2);
  Person p3 = new Person("1002","1000",1);
  Person p4 = new Person("1003","1001",2);
  Person p5 = new Person("1004","1001",1);
  Person p6 = new Person("1005","1001",1);
  Person p7 = new Person("1006","1002",1);
  Person p8 = new Person("1007","1002",1);
  Person p9 = new Person("1008","1002",1);
  dataSource.add(p1);
  dataSource.add(p2);
  dataSource.add(p3);
  dataSource.add(p4);
  dataSource.add(p5);
  dataSource.add(p6);
  dataSource.add(p7);
  dataSource.add(p8);
  dataSource.add(p9);
 }
 
 public static void main(String[] args) {
  
  StringBuffer sb = new StringBuffer();
  Person p1 = new Person("1000","",1);
  findChilds(dataSource,sb,p1);
  sb.deleteCharAt(sb.length()-1);
  System.out.println(sb.toString());
 }

 private static void findChilds(List<Person> pers,StringBuffer sb,Person person){
  sb.append("{\"id\":\""+person.getId()+"\"");
  List<Person> temps = getChilds(pers,person);
  if(temps.size()>0){
   sb.append(",child:[");
   for(Person ds : temps){       
    findChilds(pers,sb,ds);
   }
   sb.deleteCharAt(sb.length()-1);
   sb.append("]");
  }
  sb.append("},");
 }
 private static List<Person> getChilds(List<Person> pers,Person person){
  List<Person> per= new ArrayList<Person>();
  for(Person p : pers){
   if(person.getId().equals(p.getParentId())){
    per.add(p);
   }
  }
  return per;
 }
}