db_conn.java

一个简单的网上商店系统

package JavaBean;

import java.io.PrintWriter;
import java.sql.*;


public class DB_Conn {
	
	private String driverName="com.mysql.jdbc.Driver";      //驱动程序名
	private String userName="root";                         //数据库用户名
	private String userPwd="root";                        //密码
    private String dbName="netshop";                        //数据库名
    private String url="jdbc:mysql://localhost:3306/"+dbName+
                    "?user="+userName+"&password="+userPwd+
                    "&useUnicode=true&characterEncoding=gb2312";    //连接字符串
    private  java.sql.Connection conn=null;                          //数据库连接对象
    public java.sql.Statement sm=null;                               //数据库语句对象
  //  private PrintWriter out = null;    
    // 建立数据库连接
    public boolean ConnectDB(){
	
    	 try {
    		 Class.forName(driverName).newInstance();
        	 conn=DriverManager.getConnection(url);  //获得数据库连接
        	 sm=conn.createStatement();
        	 return true;
         } catch(Exception e) {
    		 e.printStackTrace();		 
        	// out.print("数据库连接失败!");
        	 return false;
    	 }
    }
    
    public void CloseDB(){
    	try {
			if (sm != null) {
				sm.close();
			}
			conn.close();
		} catch (SQLException SqlE) {
			SqlE.printStackTrace();
			//out.print("数据库关闭失败！");
		}
    
   }
}