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import java.io.*;
import java.sql.*;
public class DBConn {
 private String ADDRESS ;
 private int PORT ;
 private String DBNAME ;
 private String USERNAME ;
 private String PASSWORD ;
 private Connection conn ;
 private PreparedStatement pstmt ;
 private Statement stmt ;
 private ResultSet rs ;
 
 
 /***
  * Á¬½ÓMYSQLÊý¾Ý¿â
  * @return
  */
 public Connection getMySqlConn(){
  try{
   ADDRESS = "127.0.0.1";
   PORT = 3306;
   DBNAME = "test";
   USERNAME = "root";
   PASSWORD = "123456";
   if(conn==null){
    Class.forName("com.mysql.jdbc.Driver");
    conn = DriverManager.getConnection("jdbc:mysql://"+ADDRESS+":"+PORT+"?user="+USERNAME+"&password="+PASSWORD+"&useUnicode=true&characterEncoding=utf8");
   }
  }catch(Exception e){
   e.printStackTrace();
  }
  return conn;
 }
 
 
 /***
  * Á¬½ÓMSSQLÊý¾Ý¿â
  * @return
  */
 public Connection getMSSqlConn(){
  try{
   
   ADDRESS = "127.0.0.1";
   PORT = 1433;
   DBNAME = "mytest";
   USERNAME = "sa";
   PASSWORD = "";
   
   if(conn==null){
    Class.forName("net.sourceforge.jtds.jdbc.Driver");
    conn = DriverManager.getConnection("jdbc:jtds:sqlserver://"+ADDRESS+":"+PORT,USERNAME,PASSWORD);
   }
  }catch(Exception e){
   e.printStackTrace();
  }
  return conn;
 }
 
 /**
  * ¹Ø±ÕÊý¾Ý¿âÁ¬½Ó
  * @return
  */
 public void closeConn(){
  try{
   


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