chanping.java

这是我写的产品管理系统

package sn.ChangPingXiaoShou;
import cn.KeKuXiaoShao.*;
import com.yonghuxiaoshou.*;
import deng.shaoxiao.*;
import sun.BuMenXiaoShou.*;
import xiao.xiaoshouxiaoshou.*;
import yuan.xiaoshou.*;

//定义一个产品信息表连接库
import java.sql.*;
import java.util.*;
public class ChanPing {
		//驱动类
	private static final String sDBDriver = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
	//连接字符串
	private static final String url = "jdbc:sqlserver://localhost:1433;databasename = XiaoShou";
	//连接姓名
	private static final String user = "zhou";
	//连接密码
	private static final String pwd = "111111";
	//连接发送集
	private static PreparedStatement ps = null;
	//连接结果集
	private static ResultSet rs = null;
	//定义一个连接的方法
	public static Connection getconn(){
		Connection conn = null;
		try{
			Class.forName(sDBDriver);
			conn = DriverManager.getConnection(url,user,pwd);
		}
		catch(java.lang.ClassNotFoundException e){
			System.out.println ("找不到文件");
		}
		catch(SQLException e){
			System.out.println ("连接失败");
		}
		return conn;
	}
	//1定义一个查询的方法(不带参数)
	public static ResultSet select(){
		Connection conn = getconn();
		ArrayList arr = new ArrayList();
		try{
			ps = conn.prepareStatement("select * from t_products");
			rs = ps.executeQuery();
		}
		catch(SQLException e){
			System.out.println ("查询失败");
		}
		return rs;
	}
	//1定义一个带参数的查询方法
	public static ArrayList select(int D_id){
		Connection conn = getconn();
		ArrayList arr = new ArrayList();
		try{
			ps = conn.prepareStatement("select * from t_products where D_id = ?");
			ps.setInt(1,D_id);
			rs = ps.executeQuery();
			if(rs != null){
				while(rs.next()){
					arr.add(rs.getInt(1));
					arr.add(rs.getString(2));
					arr.add(rs.getString(3));
					arr.add(rs.getString(4));
				}
			}
		}
		catch(SQLException e){
			System.out.println ("带参数查询失败");
		}
		finally{
			try{
				ps.close();
				conn.close();
			}
			catch(SQLException e){
				System.out.println ("sql带参数查询失败");
			}
		}
		return arr;
	}
	//2定义一个添加的方法
	public static int insert(int D_id,String D_name,String D_price,String D_remark){
		Connection conn = getconn();
		int num = 0;
		try{
			ps = conn.prepareStatement("insert into t_products values(?,?,?,?)");
			ps.setInt(1,D_id);
			ps.setString(2,D_name);
			ps.setString(3,D_price);
			ps.setString(4,D_remark);
			num = ps.executeUpdate();
		}
		catch(SQLException e){
			System.out.println ("添加失败");
		}
		finally{
			try{
				ps.close();
				conn.close();
			}
			catch(SQLException e){
				System.out.println ("sql添加失败");
			}
		}
		return num;
	}
	//3定义一个修改的方法
	public static int update(int D_id,String D_name,String D_price,String D_remark,int D_id1){
		Connection conn = getconn();
		int num = 0;
		try{
			ps = conn.prepareStatement("update t_products set D_name = ?,D_price = ?,D_remark = ? where D_id = ?");
			ps.setString(1,D_name);
			ps.setString(2,D_price);
			ps.setString(3,D_remark);
			ps.setInt(4,D_id1);
			num =ps.executeUpdate();
		}
		catch(SQLException e){
			System.out.println ("修改失败");
		}
		finally{
			try{
				ps.close();
				conn.close();
			}
			catch(SQLException e){
				System.out.println ("sql修改失败");
			}
		}
		return num;
	}
	
//	//4定义一个删除的方法不带参数的删除方法
//	private int delete(){
//		Connection conn = getconn();
//		int num = 0;
//		try{
//			ps = conn.prepareStatement("delete from t_products");
//			num = ps.executeUpdate();
//		}
//		catch(SQLException e){
//			System.out.println ("删除失败");
//		}
//		finally{
//			try{
//				ps.close();
//				conn.close();
//			}
//			catch(SQLException e){
//				System.out.println ("sql删除失败");
//			}
//		}
//		return num;
//	}
	//4定义一个代参数的删除方法
	public static int delete(int D_id){
		Connection conn = getconn();
		int num = 0;
		try{
			ps = conn.prepareStatement("delete from t_products where D_id = ?");
			ps.setInt(1,D_id);
			num = ps.executeUpdate();
		}
		catch(SQLException e){
			System.out.println ("带参数删除失败");
		}
		finally{
			try{
				ps.close();
				conn.close();
			}
			catch(SQLException e){
				System.out.println ("sql带参数删除失败");
			}
		}
		return num;
	}
}