java 如何对SQL2005 连接 和一些对数据查找 更新的操作

//给你一个类用
//DBConn.java
package db;
//include required classes
import java.io.*;
import java.lang.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;

//==========================================
// Define Class DBConn
//==========================================
public class DBConn_ms{
static String sql_driver = "com.microsoft.sqlserver.jdbc.SQLServerDriver";
static String sql_url = "jdbc:sqlserver://192.168.100.1:1433";
static String sql_DBName = "asd";
static String user = "bbb";
static String pwd = "123456";

static Connection conn = null;
static Statement stmt = null;
static ResultSet rs = null;
static PreparedStatement pstmt=null;

public DBConn_ms(){
try{
Class.forName(sql_driver);//
this.conn = DriverManager.getConnection(sql_url + ";databaseN