~~~ package JDBC.util; /** * @author: hcf * @qq: 46914685 * @email: 46914685@qq.com */ import java.io.FileReader; import java.io.IOException; import java.net.URL; import java.sql.*; import java.util.Properties; /** * JDBC工具類 */ public class JDBCUtils { private static String url; private static String user; private static String password; private static String driver; /** * 文件的讀取,只需要讀取一次即可拿到這些值.使用靜態代碼塊 */ static { //讀取資源文件,獲取值 try { //1.創建Properties集合類 Properties pro = new Properties(); //2.加載文件 //獲取src路徑下的文件的方式-->ClassLoader類加載器 ClassLoader classLoader = JDBCUtils.class.getClassLoader(); URL res = classLoader.getResource("jdbc.properties"); String path = res.getPath(); pro.load(new FileReader(path)); //3.獲取數據,賦值 url = pro.getProperty("url"); user = pro.getProperty("user"); password = pro.getProperty("password"); driver = pro.getProperty("driver"); //4.注冊驅動 Class.forName(driver); } catch (IOException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } } /** * 獲取連接 * * @return 連接對象 */ public static Connection getConnection() throws SQLException { return DriverManager.getConnection(url, user, password); } /** * 釋放資源 * * @param stmt * @param conn */ public static void close(Statement stmt, Connection conn) { if (stmt != null) { try { stmt.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (conn != null) { try { conn.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } } /** * 釋放資源(重載) * * @param rs * @param stmt * @param conn */ public static void close(ResultSet rs, Statement stmt, Connection conn) { if (rs != null) { try { rs.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (stmt != null) { try { stmt.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } if (conn != null) { try { conn.close(); } catch (SQLException throwables) { throwables.printStackTrace(); } } } } ~~~