userdao.java~6~

本程序是用java编写的一个关于银行存款取款的软件

package dao;

import javax.sql.DataSource;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.ResultSet;

public class UserDAO {
    DataSource ds;
    public UserDAO() {

        try {
            InitialContext ic = new InitialContext();
            ds = (DataSource) ic.lookup("java:comp/env/jdbc/eBank");
        } catch (NamingException ex) {
            ex.printStackTrace();
        }
    }

    public boolean addCustomer(String username, String password) {
        try {
            Connection con = ds.getConnection();
            String sql =
                    "insert into j2eeappuser values(?,?,seq_user.nextval)";
            PreparedStatement pstmt = con.prepareStatement(sql);
            pstmt.setString(1, username);
            pstmt.setString(2, password);

            pstmt.executeUpdate();
            pstmt.close();
            con.close();
            return true;
        } catch (SQLException ex) {
            ex.printStackTrace();
            return false;
        }
    }

    public boolean deleteCustomer(int id) {
        try {
            Connection con = ds.getConnection();
            String sql = "delete from j2eeappuser where userid=?";
            PreparedStatement pstmt = con.prepareStatement(sql);
            pstmt.setInt(1, id);
            pstmt.executeUpdate();
            pstmt.close();
            con.close();
            return true;
        } catch (SQLException ex) {
            ex.printStackTrace();
            return false;
        }

    }

    public boolean validate(String name, String password) {
        try {
            Connection con = ds.getConnection();
            String sql =
                    "select * from j2eeappuser where username=? and password=?";
            PreparedStatement pstmt = con.prepareStatement(sql);
            pstmt.setString(1, name);
            pstmt.setString(2, password);
            ResultSet rs = pstmt.executeQuery();
            boolean flag = false;
            if (rs.next()) flag = true;
            rs.close();
            pstmt.close();
            con.close();
            return flag;
        } catch (SQLException ex) {
            ex.printStackTrace();
            return false;
        }

    }

    public int getUserid(String name, String password) {
        try {
            Connection con = ds.getConnection();
            String sql =
                    "select * from j2eeappuser where username=? and password=?";
            PreparedStatement pstmt = con.prepareStatement(sql);
            pstmt.setString(1, name);
            pstmt.setString(2, password);
            ResultSet rs = pstmt.executeQuery();

            rs.next();
            int id = rs.getInt("userid");
            rs.close();
            pstmt.close();
            con.close();
            return id;
        } catch (SQLException ex) {
            ex.printStackTrace();
            return 0;
        }

    }
}