dbconnection.java

主要实现的是用户注册

package com.hh.db;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class DBConnection {
private static DBConnection db=null;
private static Connection conn=null;
private Statement st=null;
private DBConnection() throws Exception
  {
    String user="sa";
	String passwd="111111";
	String driver="com.microsoft.jdbc.sqlserver.SQLServerDriver";
	String url="jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=abc";
    	if(conn==null)
    	{
    	   Class.forName(driver);
    	 conn=DriverManager.getConnection(url,user,passwd);
    	 st=conn.createStatement();
    	
    	 
    	}
 }
public static DBConnection getInstance()
 {
    if(db==null)
    {
	try{
	db=new DBConnection();
	}
	catch(Exception e)
	{
	    conn=null;
	    return null;
	}
    }
    return db;
}
public void myupdate(String sql) 
{
    try {
		if(st!=null)
		{
		
			st.executeUpdate(sql);
			
		}
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}

    
}
public ResultSet myread(String sql) throws SQLException
{
    ResultSet rs=null;
    if(st!=null)
    {
	rs=st.executeQuery(sql);
	 return rs;
    }
    else
    {
    	return null;
    }

   
}
public void stop()
{
    if(conn!=null)
    {
	try {
	    st.close();
	    conn.close();
	} catch (SQLException e) {
	    // TODO Auto-generated catch block
	   
	}
	finally
	{
	    conn=null;
	}
    }
}

}