JDBC查询指定条件的数据

使用select语句的条件查询，需要用到where子句。

 package qddx.JDBC;
 import java.sql.*;
 public class QueryById {

     public bbsVo QuerybbsVoById(int id){
         bbsVo vo = null;
         Connection conn = null;
         PreparedStatement pst = null;
         ResultSet rs = null;
         try{
         conn = JDBC_Connection.getConnection();
         pst = conn.prepareStatement("select * from article where id=?");
         pst.setInt(1, id);//设置条件id
         rs=pst.executeQuery();
         while(rs.next()){//结果集存在则进行遍历
             vo = new bbsVo();
             vo.setId(rs.getInt("id"));
             vo.setPid(rs.getInt("pid"));
             vo.setRootid(rs.getInt("rootid"));
             vo.setCont(rs.getString("cont"));
             vo.setPdate(rs.getTimestamp("pdate"));
             vo.setIsleaf(rs.getInt("isleaf"));
             vo.setTitle(rs.getString("title"));

         }
         }catch(SQLException e){
             e.printStackTrace();
         }finally{
             JDBC_Connection.free(rs, conn, pst);
         }
         return vo;

     }
     public static void main(String[] args) {
         // TODO Auto-generated method stub
         QueryById byid = new QueryById();
         int id = 3;
         bbsVo vo = byid.QuerybbsVoById(id);
         if(vo!=null){
             System.out.print("id\t");
             System.out.print("pid\t");
             System.out.print("rootid\t");
             System.out.print("title\t\t");
             System.out.print("cont\t");
             System.out.print("pdate\t");
             System.out.print("isleaf\t");
             System.out.println();
             System.out.print(vo.getId()+"\t");
             System.out.print(vo.getPid()+"\t");
             System.out.print(vo.getRootid()+"\t");
             System.out.print(vo.getTitle()+"\t");
             System.out.print(vo.getCont()+"\t");
             System.out.print(vo.getPdate()+"\t");
             System.out.print(vo.getIsleaf()+"\t");
         }else{
             System.out.println("id为"+id+" 的用户不存在");
         }
     }

 }