JDBC查询数据库中的数据

 1 package qddx.JDBC;
 2 import java.util.*;
 3 import java.sql.*;
 4 //查询操作
 5 public class Query {
 6 
 7     public List<bbsVo> showBBS(){
 8         Connection conn = null;
 9         Statement st = null;
10         ResultSet rs = null;
11         List<bbsVo> list = new ArrayList<bbsVo>();//声明一个List集合，用于存放查询出的数据
12         try{
13         conn = JDBC_Connection.getConnection();//连接数据库
14         st = conn.createStatement();//创建Statement对象
15         rs=st.executeQuery("select * from article");
16         while(rs.next()){//结果集存在则进行遍历
17             bbsVo vo = new bbsVo();
18             vo.setId(rs.getInt("id"));
19             vo.setPid(rs.getInt("pid"));
20             vo.setRootid(rs.getInt("rootid"));
21             vo.setCont(rs.getString("cont"));
22             vo.setPdate(rs.getTimestamp("pdate"));
23             vo.setIsleaf(rs.getInt("isleaf"));
24             vo.setTitle(rs.getString("title"));
25             
26             list.add(vo);//把每次获得的对象添加到list集合中
27         }
28         }catch(SQLException e){
29             e.printStackTrace();
30         }finally{
31             JDBC_Connection.free(rs, conn, st);
32             
33         }
34         return list;
35     }
36     public static void main(String[] args) {
37         // TODO Auto-generated method stub
38         Query query = new Query();
39         List<bbsVo> list = query.showBBS();//调用查询方法
40         if(list!=null){
41             System.out.print("id    ");
42             System.out.print("pid  ");
43             System.out.print("rootid  ");
44             System.out.print("title    ");
45             System.out.print("cont            ");
46             System.out.print("pdate           ");
47             System.out.print("isleaf  ");
48             System.out.println();
49             for(int i=0;i<list.size();i++){
50                 System.out.print(list.get(i).getId()+"\t");
51                 System.out.print(list.get(i).getPid()+"\t");
52                 System.out.print(list.get(i).getRootid()+"\t");
53                 System.out.print(list.get(i).getTitle()+"\t");
54                 System.out.print(list.get(i).getCont()+"\t");
55                 System.out.print(list.get(i).getPdate()+"\t");
56                 System.out.print(list.get(i).getIsleaf()+"\t");
57                 System.out.println();
58             }
59         }
60     }
61 }