userdb.java

股票投资管理系统

package db;

import bean.*;
import java.sql.*;

public class UserDB {
	
	private Connection con;
	private Statement stm; 
	private PreparedStatement ps;
	private ResultSet rs;
	
	public UserDB(){
		con = null;
		stm = null;
		ps = null;
		rs = null;
	}
	
	public boolean checkLogin(UserBean ub){
		
		boolean flag = false;
		con = ConDB.getCon();
		try{
			String sql = "select * from user where user_name='"+ub.getUser_name()+"' and user_password='"+ub.getUser_password()+"'";
			stm = con.createStatement();
			rs = stm.executeQuery(sql);
			if(rs.next())
				flag = true;
			rs.close();
			stm.close();
			con.close();
				
		}catch(SQLException e){
			flag = false;
			e.toString();
		}
		
		return flag;
	}
	
	public int insertUser(UserBean ub){
		
		int result = 0;
		con = ConDB.getCon();
		try{
			
			String sql = "insert into user values(default,?,?)";
			ps = con.prepareStatement(sql);
			ps.setString(1, ub.getUser_name());
			ps.setString(2, ub.getUser_password());
			result = ps.executeUpdate();	
			ps.close();
			con.close();
						
		}catch(SQLException e){
			result = 0;
			e.toString();
		}
		
		return result;
	}
	
	
	public boolean checkUser_name(UserBean ub){
		boolean flag = false;
		con = ConDB.getCon();
		try{
			String sql = "select * from user where user_name ='"+ub.getUser_name()+"'";
			stm = con.createStatement();
			rs = stm.executeQuery(sql);
			if(!rs.next())
				flag = true;
			rs.close();
			stm.close();
			con.close();

		}catch(SQLException e){
			flag = false;
			e.toString();
		}
		return flag;
	}
	
	
	public int changePassword(String user_name,String user_password){
		con = ConDB.getCon();
		int result = 0;
		String sql = "update user set user_password=? where user_name=?";
		try {
			ps = con.prepareStatement(sql);
			ps.setString(1, user_password);
			ps.setString(2, user_name);
			result = ps.executeUpdate();
		} catch (SQLException e) {
			result = 0;
			e.printStackTrace();
		}
		
		try {
			ps.close();
			con.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		return result;
	}

}