database.java~105~

基于JSP的网上书店.功能较为全面 开发环境:sql server2000+tomcat+jdk

package bookshop.util;
/**
 * <p>数据库连接专用包 </p>
 * <p>Copyright: wxy Copyright (c) 2004</p>
 * <p>Company:juanjuan book shop online </p>
 * @by :wxy
 * @version 1.0
 */
import java.sql.*;
import javax.sql.*;
import javax.naming.*;
public class DataBase {
  public Connection conn;
  public Statement stmt;
  public ResultSet rs=null;
  public InitialContext ctx=null;
  DataSource ds = null;
  public String sqlStr="";
  public String m_strErrMsg = "";


  public DataBase() {
    this.connect();
  }

 public void finalize()
 {
    try
    {
      if (rs != null) {
        rs.close(); ;
      }
      if( stmt != null )
      {
        stmt.close();
      }
      if( conn != null)
      {
         conn.close();
      }

    }
    catch(Exception ex)
    {
      System.out.println("connect db error:"+ex.getMessage());
    }
 }

 public boolean connect(){

   boolean  bSuccess = true;
   //1) 使用MySQL数据库
   /*
      try{
        Class.forName("org.gjt.mm.mysql.Driver").newInstance();
        String url ="jdbc:mysql://localhost/BookStore?user=wxy&useUnicode=true&characterEncoding=8859_1";
        conn=DriverManager.getConnection(url);
        stmt = conn.createStatement ();
        bSuccess = true;
       }catch(Exception ee){
        m_strErrMsg = "数据库错误：" + ee.getMessage();
        System.out.println("connect db error:"+ee.getMessage());
        return false;
       }
      */

     //2) 使用数据库连接池
      try
      {
        ctx = new InitialContext();
        if (ctx == null)
        {
          throw new Exception("没有匹配的上下文环境");
        }

        ds = (DataSource) ctx.lookup("java:comp/env/jdbc/SqlServermidp");
        if (ds == null)
        {
          throw new Exception("没有匹配的数据库");
        }
        conn = ds.getConnection();
        stmt=conn.createStatement();
        bSuccess = true;
      }
      catch(Exception ee)
      {
        m_strErrMsg = "使用连接池连接数据库时错误（请检查Server.xml配置）：" + ee.getMessage();
        System.out.println("connect db error:"+ee.getMessage());
        bSuccess = false;
      }

      //3) 如果没有找到数据库连接池配置，则偿试采用下面的配置
      if( !bSuccess && false )
      {
        try
        {
          Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();
          String url = "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=bookstore";
          String user = "sa";
          String password = "";
          conn = DriverManager.getConnection(url, user, password);
          stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
                                      ResultSet.CONCUR_UPDATABLE);
          bSuccess = true;
        }
        catch (Exception ee)
        {
          m_strErrMsg = "使用JDBC驱动连接数据库错误：" + ee.getMessage();
          System.out.println("connect db error:" + ee.getMessage());
          bSuccess = false;
        }
      }

      return bSuccess;
    }

 public void close()
 {
    try{
      if(rs!=null)rs.close();
      if(stmt!=null)stmt.close();
      if(conn!=null)conn.close();

    }catch(Exception ee){
       System.out.println("connect db error:"+ee.getMessage());
       return ;
      }

 }

 public static void main(String[] args) {
     try{
            DataBase db = new DataBase();
            db.connect();
          }catch(Exception e){
            e.printStackTrace();
          }
        }
}