一个简单封装的jdbc工具类

import java.sql.*;import javax.sql.*;public final class JdbcUtil {/** * @param args */private static String url = "jdbc:mysql://localhost:3306/jdbc"; // jdbc:mysql:///jdbc 本地默认端口可以省略private static String user = "root";private static String password = "123456";private JdbcUtil() { }static {try {Class.forName("com.mysql.jdbc.Driver");} catch (ClassNotFoundException e) {throw new ExceptionInInitializerError(e);}}public static Connection getConnection() throws SQLException{return DriverManager.getConnection(url, user, password);}public static void free(ResultSet rs, Statement st, Connection conn) {try {if (rs != null) {rs.close();}} catch (SQLException e) {e.printStackTrace();} finally {try {if (st != null) {st.close();}} catch (SQLException e) {e.printStackTrace();} finally {if (conn != null) {try {conn.close();} catch (SQLException e) {e.printStackTrace();}}}}}}

static块用来注册驱动

getConnection函数用来获取连接

free函数用来安全的释放资源