JDBC查詢指定條件的數據

使用select語句的條件查詢，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);//設置條件id
        rs=pst.executeQuery();
        while(rs.next()){//結果集存在則進行遍歷
            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為"+id+" 的用戶不存在");
        }
    }

}