package day8;

import java.sql.*;

public class DBAccess {
    Connection conn = null;
    public DBAccess() {
        new sun.jdbc.odbc.JdbcOdbcDriver();
        //new com.microsoft.jdbc.sqlserver.SQLServerDriver();
    }

    public DBAccess(String driver) {
        try {
            Class.forName(driver);
        } catch (Exception ex) {
        }
    }

    public void open() {
        String url = "jdbc:odbc:ttt";
//        url="jdbc:odbc:Driver="+
//            "{Microsoft Access Driver (*.mdb)}"+
//            ";dbq=d:/1.mdb";
        try {
            conn = DriverManager.getConnection(
                    url, "", "");
        } catch (Exception ex) {

        }
    }

    public ResultSet query(String sql) {
        ResultSet rs = null;
        if (conn == null) {
            open();
            if (conn == null) {
                return null;
            }
        }
        Statement stmt = null;
        try {
            stmt = conn.createStatement();
            rs = stmt.executeQuery(sql);
        } catch (Exception ex) {
            System.out.println(
                    "ex in query:" + ex.getMessage());
            rs = null;
        }
        return rs;
    }

    public int update(String sql) {
        if (conn == null) {
            open();
            if (conn == null) {
                return -1;
            }
        }
        Statement stmt = null;
        int ret = -1;
        try {
            stmt = conn.createStatement();
            ret = stmt.executeUpdate(sql);
        } catch (Exception ex) {
            System.out.println(
                    "ex in update:" + ex.getMessage());
            ret = -1;
        } finally {
            try {
                conn.close();
            } catch (Exception ex) {}
        }
        return ret;
    }

    public void close() {
        try {
            conn.close();
        } catch (Exception ex) {
        }
    }
}