Java 8新特性之集合

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.stream.Collectors; public class Test {    public static void main(String[] args) {
    Grade grade = new Grade();
    grade.name = "三年级一班";
    List<Students> sList = new ArrayList<>();//熟知的钻石语法
    for(int i = 0;i < 10;i++){
      Students temp = new Students();
      temp.name = "王"+i;
      temp.age = i;
      temp.grade= grade;
      sList.add(temp);
    }
    List<Map<String, Object>> data = sList.stream()
                          .map(student->{
          Map<String,Object> map = new TreeMap<String, Object>();
          map.put("姓名:", student.name);
          map.put("年龄:", student.age);
          map.put("所在班级:", student.grade.name);
          return map;
    }).collect(Collectors.toList());
    for(int i =0;i<data.size();i++) {
      Map<String, Object> map = data.get(i);
      System.out.print(map.get("姓名:")+" ");
      System.out.print(map.get("年龄:")+" ");
      System.out.print(map.get("所在班级:")+"\n");
    }
  }
} class Students{
    public String name;
    public Integer age;
    public Grade grade;
} class Grade{
    public String name;
}

本人新手,写随笔只是记录成长过程,对大家有帮助的地方,可以采纳,写的不好的地方也可以批评指正,谢谢!
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