Java连接常见数据库代码

1.连接SQL server 2005数据库

	public class JDBCConnection {
	 /**
	  * DRIVER 数据库驱动
	  * URL 数据库地址
	  * USER_NAME 数据库用户名
	  * PASSWORD 数据库登录密码
	  */
	 
	 private static final String DRIVER="com.microsoft.sqlserver.jdbc.SQLServerDriver";
	 private static final String URL="jdbc:sqlserver://localhost:1433;DatabaseName=LibraryManagement";
	 private static final String USER_NAME="sa";
	 private static final String PASSWORD="123456";
	 private static Connection conn;
	 private static final ThreadLocal<Connection> threadLocal = new ThreadLocal<Connection>();
	 //通过静态代码块加载JDBC驱动
	 
	 static
	 {
	  try{
	   Class.forName(DRIVER).newInstance();
	  }catch(ClassNotFoundException e)
	  {
	   e.printStackTrace();
	  }
	  catch(Exception e)
	  {
	   e.printStackTrace();
	  }
	 }
	 /**
	  * 功能：建立与数据库的连接
	  * @return Connection的实例
	  *@throws ClassNotFound,SQLException
	   */
	 public static Connection getConnection()
	 {
	  //从线程中获得数据库连接
	  conn=threadLocal.get();
	  if(conn==null)
	  {
	   try{
	    conn=DriverManager.getConnection(URL,USER_NAME,PASSWORD);
	    //将数据库连接保存到线程中
	    threadLocal.set(conn);
	   }catch(SQLException e)
	   {
	    e.printStackTrace();
	   }
	  }
	  return conn;
	 }
	}

2.连接MySQL数据库

	 public  Connection getConnection() throws ClassNotFoundException {
	  String url = "jdbc:mysql://localhost:3306/mesdb";
	  String name = "root";
	  String passw = "123456";
	  Class.forName("com.mysql.jdbc.Driver");
	  try {
	   Connection conn=DriverManager.getConnection(url,name,passw);
	   return conn;
	  } catch (Exception e) {
	   e.printStackTrace();
	   return null;
	  }
	 }

3.连接Oracle数据库

public OracleJDBC {
 public  Connection getConnection() throws ClassNotFoundException {  
      String url = "jdbc:oracle:thin:@192.168.102.243:1521:orcl";  
        String name = "training";   String passw = "123456"; 
       Class.forName("oracle.jdbc.driver.OracleDriver");  
     try {    
             Connection conn =DriverManager.getConnection(url,name,passw);   
             return conn;  
            } catch (Exception e)
                     {    
                        e.printStackTrace();     
                         return null; 
                    }
   }