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import java.io.FileReader;import java.net.URL;import java.sql.*;import java.util.Properties;public class JDBCUtils {   	private static String url;    private static String user;    private static String password;    private static String driver;    static {   //读取资源文件                try {               //获取src路径下的文件----类加载器            ClassLoader classLoader = JDBCUtils.class.getClassLoader();            URL res = classLoader.getResource("jdbc.properties");            String path = res.getPath();            //1.创建Properties集合类            Properties p = new Properties();            //2.加载文件            p.load(new FileReader(path));            //3.获取数据，赋值            url = p.getProperty("url");            user = p.getProperty("user");            password = p.getProperty("password");            driver = p.getProperty("driver");            //注册驱动            Class.forName(driver);        } catch (Exception e) {               e.printStackTrace();        }     }    //获取连接    public static Connection getConn() throws SQLException {               return DriverManager.getConnection(url, user, password);    }    //释放资源    public static void closeSource(ResultSet rs, Statement stmt, Connection conn) {           if (rs != null) {               try {                   rs.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }        if (stmt != null) {               try {                   stmt.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }        if (conn != null) {               try {                   conn.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }    }    public static void closeResultSet(ResultSet rs){           if (rs != null) {               try {                   rs.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }    }    public static void closeStatement(Statement stmt){           if (stmt != null) {               try {                   stmt.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }    }    public static void closeConnection(Connection conn){           if (conn != null) {               try {                   conn.close();            } catch (SQLException e) {                   e.printStackTrace();            }        }    }}