java——JDBC——JDBC各个类详解——练习

左手的ㄟ右手 2023-09-28 23:38 18阅读 0赞

代码：
                        Statement stmt = null;
                        Connection conn = null;
                        try {
                            //1. 注册驱动
                            Class.forName("com.mysql.jdbc.Driver");
                            //2. 定义sql
                            String sql = "insert into account values(null,'王五',3000)";
                            //3.获取Connection对象
                            conn = DriverManager.getConnection("jdbc:mysql:///db3", "root", "root");
                            //4.获取执行sql的对象 Statement
                            stmt = conn.createStatement();
                            //5.执行sql
                            int count = stmt.executeUpdate(sql);//影响的行数
                            //6.处理结果
                            System.out.println(count);
                            if(count > 0){
                                System.out.println("添加成功！");
                            }else{
                                System.out.println("添加失败！");
                            }
                
                        } catch (ClassNotFoundException e) {
                            e.printStackTrace();
                        } catch (SQLException e) {
                            e.printStackTrace();
                        }finally {
                            //stmt.close();
                            //7. 释放资源
                            //避免空指针异常
                            if(stmt != null){
                                try {
                                    stmt.close();
                                } catch (SQLException e) {
                                    e.printStackTrace();
                                }
                            }
                
                            if(conn != null){
                                try {
                                    conn.close();
                                } catch (SQLException e) {
                                    e.printStackTrace();
                                }
                            }
                        }