Java mysql数据库连接Demo1

public class MysqlUtil {     /**      * 链接数据库      */     /**      * 方法一：      * 加载驱动的方法不止一种，但这种最常用       */     public static Connection getConnectionOne(String database,String username,String password){         try {             Class.forName("com.mysql.jdbc.Driver");             Connection connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/"+database,username,                     password);             return connection;         }catch(Exception e){             e.printStackTrace();         }         return null;     }     /**      * 方法二：      * 利用properties文件      * ：：：：： 在Web 编程时 文件难以定位       */     public static Connection getConnectionTwo() {         /**          * 建立文件          */         Properties pro = new Properties();          InputStream in = MysqlUtil.class.getClassLoader().getResourceAsStream("mysqllog.properties");         try {             pro.load(in);             Class.forName(pro.getProperty("driver"));             String username = pro.getProperty("user");             String password = pro.getProperty("password");             String database = pro.getProperty("database");             String url = pro.getProperty("url");              Connection connection = DriverManager.getConnection(url+database,username,password);             return connection;         } catch (Exception e) {             e.printStackTrace();         }          return null;     }     // Connection ,Statement, ResultSet 这几个资源的关闭是有顺序的     public static void close (Object...objects) throws MysqlCloseException {         Map<String,Object> map = new HashMap();         for(Object o : objects){             if(o instanceof ResultSet){                 map.put("ResultSet",o);             }else if(o instanceof Connection){                 map.put("Connection",o);             }else if(o instanceof Statement){                 map.put("Statement",o);             }else if(o instanceof PreparedStatement){                 map.put("PreparedStatement",o);             }else{                 throw new MysqlCloseException("关闭异常，不能处理");             }         }         Object obj = map.get("ResultSet");         if(obj!=null){             ResultSet r = (ResultSet)obj;             try {                 r.close();                 map.remove("ResultSet");             } catch (SQLException e) {                 e.printStackTrace();             }         }         obj = map.get("PreparedStatement");         if(obj!=null){             PreparedStatement p = (PreparedStatement)obj;             try {                 p.close();                 map.remove("PreparedStatement");             } catch (SQLException e) {                 e.printStackTrace();             }         }         obj = map.get("Statement");         if(obj!=null){             Statement s = (Statement)obj;             try {                 s.close();                 map.remove("Statement");             } catch (SQLException e) {                 e.printStackTrace();             }         }         obj = map.get("Connection");         if(obj!=null){             Connection c = (Connection)obj;             try{                 c.close();                 map.remove("Connection");             }catch(SQLException e){                 e.printStackTrace();             }         }     } }

来源：博客园

作者：DiYong

链接：https://www.cnblogs.com/Diyo/p/11421665.html