直接上下代码:
1 package com.learn.jdbc.chap05; 2 3 import java.sql.Connection; 4 import java.sql.PreparedStatement; 5 import java.sql.ResultSet; 6 import java.util.ArrayList; 7 import java.util.List; 8 9 import com.learn.jdbc.model.Album; 10 import com.learn.jdbc.util.DbUtil; 11 /** 12 * 使用ResultSet结果集(数据查询) 13 * @author Administrator 14 * 15 */ 16 public class Demo1 { 17 18 private static DbUtil dbUtil=new DbUtil(); 19 20 private static void listAlbum() throws Exception{ 21 Connection con = dbUtil.getCon(); 22 String sql="select * from sp_album"; 23 PreparedStatement pstmt = con.prepareStatement(sql); 24 ResultSet rs = pstmt.executeQuery(); // 返回结果集 ResultSet 25 while(rs.next()){ 26 // 下面的写法 在工作中 很少用 27 int id=rs.getInt(1); 28 String name=rs.getString(2); 29 int uid=rs.getInt(3); 30 long time=rs.getLong(4); 31 System.out.println("编号:"+id+",名称:"+name+",会员id:"+uid+",添加时间:"+time); 32 System.out.println("-----------------------"); 33 } 34 35 } 36 37 private static void listAlbum2() throws Exception{ 38 Connection con = dbUtil.getCon(); 39 String sql="select * from sp_album"; 40 PreparedStatement pstmt = con.prepareStatement(sql); 41 ResultSet rs = pstmt.executeQuery(); // 返回结果集 ResultSet 42 while(rs.next()){ 43 // 下面的写法 在工作中 经常这么写 44 int id=rs.getInt("id"); 45 String name=rs.getString("name"); 46 int uid=rs.getInt("uid"); 47 long time=rs.getLong("add_time"); 48 System.out.println("编号:"+id+",名称:"+name+",会员id:"+uid+",添加时间:"+time); 49 System.out.println("-----------------------"); 50 } 51 52 } 53 54 private static List<Album> listAlbum3() throws Exception{ 55 List<Album> albumList = new ArrayList<Album>(); 56 57 Connection con = dbUtil.getCon(); 58 String sql="select * from sp_album"; 59 PreparedStatement pstmt = con.prepareStatement(sql); 60 ResultSet rs = pstmt.executeQuery(); // 返回结果集 ResultSet 61 while(rs.next()){ 62 // 下面的写法 在工作中 经常这么写 63 int id=rs.getInt("id"); 64 String name=rs.getString("name"); 65 int uid=rs.getInt("uid"); 66 long time=rs.getLong("add_time"); 67 68 Album ab=new Album(id, name, uid, time); 69 albumList.add(ab); 70 } 71 72 return albumList; 73 } 74 75 public static void main(String[] args) throws Exception { 76 /*listAlbum(); 77 System.out.println("============================================="); 78 listAlbum2();*/ 79 List<Album> abInfo = listAlbum3(); 80 for(Album abm:abInfo){ // 此处的abm默认输出是调用父类的toString方法,要输出自定义信息,需要重写toString方法 81 System.out.println(abm); 82 //System.out.println(abm.getName()); 83 } 84 } 85 }
时间: 2024-10-03 01:57:05