表格存储数据

package 表格数据存储;

import java.util.*;

public class TestStoreData {
    public static void main(String[] args) {
        Map<String,Object>row1=new HashMap<>();//数据不确定类型时使用Object
        row1.put("id",1001);
        row1.put("姓名","张三");
        row1.put("薪水",200000);
        row1.put("入职日期","2018.5.5");
        Map<String,Object>row2=new HashMap<>();//数据不确定类型时使用Object
        row2.put("id",1002);
        row2.put("姓名","李四");
        row2.put("薪水",300000);
        row2.put("入职日期","2005.4.1");
        Map<String,Object>row3=new HashMap<>();//数据不确定类型时使用Object
        row2.put("id",1003);
        row2.put("姓名","王五");
        row2.put("薪水",3000);
        row2.put("入职日期","2020.5.4");
        List<Map<String,Object>>table =new ArrayList<>();
        table.add(row1);
        table.add(row2);
        table.add(row3);
        for(Map<String,Object>row:table){
            Set<String>keyset=row.keySet();
            for(String key: keyset){
                System.out.print(key+":"+row.get(key)+"\t");
            }
            System.out.println();
        }

    }
}

package 表格数据存储;

import java.util.*;

//每一行数据使用javabean对象存储 多行使用放到map或list中
public class TestStoreData2 {
    public static void main(String[] args) {
        User user1=new User(1001,"张三",2000,"2018.5.6");
        User user2=new User(1002,"李四",30000,"2005.5.6");
        User user3=new User(1003,"王五",3000,"2020.5.6");
        List<User>list=new ArrayList<>();
        list.add(user1);
        list.add(user2);
        list.add(user3);
        for(User u:list){
            System.out.println(u);

        }
        Map<Integer,User>map=new HashMap<>();
        map.put(1001,user1);
        map.put(1002,user2);
        map.put(1003,user3);
        Set<Integer>keyset = map.keySet();
        for(Integer key:keyset){
            System.out.println(key+"---"+map.get(key));

        }

    }


}
//一个完整的javabean 要有set和get方法 以及一个无参构造器
class User{
    private int id;
    private String name;
    private double salary;
    private String hiredate;
    public User(){

    }

    public User(int id, String name, double salary, String hiredate) {
        this.id = id;
        this.name = name;
        this.salary = salary;
        this.hiredate = hiredate;
    }

    @Override
    public String toString() {
        return "id:"+name+",salary:"+salary+",hiredate:"+hiredate;
    }
}