问个 jdbc 的不是伸手。。已经搜好长时间。。

package com.jdbc;

import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException;

public class Select {

public Student findById(String sno){
	Connection conn = null;
	PreparedStatement ps = null;
	ResultSet rs = null;
	Student s = new Student();
	try {
		conn = DBUtil.getConnection();
		StringBuilder sb = new StringBuilder();
		sb.append(" select * from student where SNO = ?");
		ps = conn.prepareStatement(sb.toString());
		ps.setString(1, sno);
		rs = ps.executeQuery();
		System.out.println(sb);
		System.out.println(rs.next());
		if(rs.next()){
			s.setSno(rs.getString("SNO"));
			s.setSname(rs.getString("SNAME"));
			s.setAge(rs.getInt("AGE"));
			s.setSex(rs.getString("AGR"));
			s.setDept(rs.getString("DEPT"));
			System.out.println(s.getSno());
			return s;
		}else{
			return null;
		}
	} catch (Exception e) {
		e.printStackTrace();
		return null;
	}finally{
		if(rs != null){
			try {
				rs.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			rs = null;
		}
		if(ps != null){
			try {
				ps.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
			ps = null;
		}
	}
}


public static void main(String[] args) {
	Select s = new Select();
	Student student = s.findById("1004");
	System.out.println(student);
}

/**
 * 控制台输出:
 * select * from student where SNO = ?
 *true
 *null
 */

}