查询数据库中的表格---通过构造方法将数据存入到List集合中---遍历进行输出

package cn.jy.demo;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class storetraverse {
public static void main(String[] args) throws SQLException {
fun1();
//fun2();
}
//通过遍历将表格中的数据存放到zhangwu1对象中(根据zhangwu1的有参构造)然后在将其存放到集合中 最后对集合进行遍历 输出结果
public static void fun1() throws SQLException{
Connection con=JDBCUtilsConfig.getConnection(); //连接 其中JDBCUtilsConfig为我自己为方便连接封装的类
String sql="SELECT * FROM zhangwu1"; //遍历我们创建的表格
PreparedStatement pst=con.prepareStatement(sql); //执行平台对象
ResultSet rs= pst.executeQuery(); //将查询的信息存放到ResultSet集合中
List<zhangwu1> list = new ArrayList<>();//创建集合 为之后的数据存入到集合中方便
while(rs.next()){
zhangwu1 zw=new zhangwu1(rs.getInt("id"),rs.getString("flname"),rs.getDouble("money"),rs.getString("zhanghu"),rs.getString("date"),rs.getString("description"));
list.add(zw);
}
for(zhangwu1 zw:list){
System.out.println(zw);
}
JDBCUtilsConfig.close(con, pst,rs);
}
//通过构造方法将一组数据用new对象的方式存入到集合中 先遍历 让后根据输入将该组数据输出
public static void fun2(){
List<zhangwu1> list=new ArrayList<>();
list.add(new zhangwu1(11,"女警",999,"4566","2015-6","优秀"));
list.add(new zhangwu1(12,"寒冰",599,"4567","2015-6","优秀"));
list.add(new zhangwu1(13,"女警1",699,"4568","2015-6","优秀"));
list.add(new zhangwu1(14,"女警2",799,"4569","2015-6","优秀"));
list.add(new zhangwu1(15,"女警3",199,"4576","2015-6","优秀"));
list.add(new zhangwu1(16,"女警4",99,"4598","2015-6","优秀"));
for(zhangwu1 zw:list){
System.out.println(zw);
}
Scanner sc=new Scanner(System.in);
System.out.println("请输入大于11小于16的整数");
int i=sc.nextInt();
for(int j=0;j<list.size();j++){
zhangwu1 item=list.get(j);
if(item.getId()==i){
System.out.println(item.getId()+" "+item.getFlname()+" "+item.getMoney());
}

}
sc.close();
}

}

posted on 2019-02-26 19:59  代我向西贝问好  阅读(681)  评论(0编辑  收藏  举报

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