studentdao.java

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package dao;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.util.ArrayList;

import po.Student;

//访问数据库
public class StudentDao {
	private Connection conn = null;
	
	public void initConnection(){//初始化数据库连接
		try{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
			conn = DriverManager.getConnection("jdbc:odbc:School","scott","tiger");
		}catch(Exception ex){ex.printStackTrace();}
	}
	
	public String getNameById(String stuId){
		String sql = "SELECT 姓名 FROM 学籍 WHERE 学号='"+stuId+"'";
		try{
			this.initConnection();
			ResultSet rs = conn.createStatement().executeQuery(sql);
			if(rs.next()){
				return rs.getString("姓名");
			}
			
		}catch(Exception ex){
			ex.printStackTrace();
		}
		finally{
			this.closeConnection();
		}
		return null;
	}
	
	public ArrayList getStuByPro(String pro){
		ArrayList stus = new ArrayList();
		String sql = "SELECT 学号,姓名,性别,出生年月,家庭住址 FROM 学籍 WHERE 家庭住址='" + pro + "'";
		try{
			this.initConnection();
			ResultSet rs = conn.createStatement().executeQuery(sql);
			while(rs.next()){
				Student stu = new Student();
				stu.setStuId(rs.getString("学号"));
				stu.setStuName(rs.getString("姓名"));
				stu.setStuSex(rs.getString("性别"));
				stu.setStuBir(rs.getString("出生年月"));
				stu.setStuAdd(rs.getString("家庭住址"));
				stus.add(stu);
			}
		}catch(Exception ex){ex.printStackTrace();}
		finally{
			this.closeConnection();
		}
		return stus;
	}
	
	public ArrayList getPros(){
		ArrayList pros = new ArrayList();
		String sql = "SELECT DISTINCT 家庭住址 FROM 学籍";
		try{
			this.initConnection();
			ResultSet rs = conn.createStatement().executeQuery(sql);
			while(rs.next()){
				pros.add(rs.getString("家庭住址"));
			}
			
		}catch(Exception ex){
			ex.printStackTrace();
		}
		finally{
			this.closeConnection();
		}
		return pros;
		
	}
	public void closeConnection(){
		try{
			if(conn!=null){
				conn.close();
				conn = null;
			}
		}catch(Exception ex){ex.printStackTrace();}
	}
}