zoukankan      html  css  js  c++  java
  • JDBC

    /**
         * jdbc建立数据库连接
         */
        public static void main(String[] args)  {
            try {
                //1.注册驱动
                //DriverManager.registerDriver(new com.mysql.jdbc.Driver());
            Class.forName("com.mysql.jdbc.Driver");
    //2.建立连接 Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/test", "root", "123456"); //3.创建statement Statement st = conn.createStatement(); //4.执行查询 String sql = "select * from tt_test"; ResultSet rs = st.executeQuery(sql); //5.遍历查询每一条数据 while(rs.next()){ String name = rs.getString("name"); int age = rs.getInt("age"); System.out.println("name="+name+"--------"+"age="+age); } rs.close(); st.close(); conn.close(); } catch (SQLException e) { e.printStackTrace(); } } }
    /**
         * jdbc使用properties配置文件连接
         */
        public static void main(String[] args) throws IOException {
            String driverClass;
            String url;
            String name;
            String password;
            //1.创建一个属性配置对象
            Properties properties = new Properties();

          //对应文件位于工程根目录
          InputStream is = new FileInputStream("jdbc.properties");

    //使用类加载器,去读取src底下的资源文件(对应文件位于src目录下)
            InputStream is = Test2.class.getClassLoader().getResourceAsStream("jdbc.properties");
            //导入输入流
            properties.load(is);
            //读取属性
            driverClass = properties.getProperty("driverClass");
            url = properties.getProperty("url");
            name = properties.getProperty("name");
            password = properties.getProperty("password");
            try {
                //1.注册驱动
                //DriverManager.registerDriver(new com.mysql.jdbc.Driver());
                Class.forName(driverClass);
                //2.建立连接
                Connection conn = DriverManager.getConnection(url, name, password);
                //3.创建statement 
                Statement st = conn.createStatement();
                //4.执行查询
                String sql = "select * from tt_test";
                
                ResultSet rs = st.executeQuery(sql);
                //5.遍历查询每一条数据
                while(rs.next()){
                    String name1 = rs.getString("name");
                    int age = rs.getInt("age");
                    System.out.println("name="+name1+"--------"+"age="+age);
                }
                rs.close();
                st.close();
                conn.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    public void testInsert() throws Exception{
            Class.forName("com.mysql.jdbc.Driver");
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost/test", "root", "123456");
            Statement st = conn.createStatement();
            //插入、删除、更新类似
            String sql = "insert into tt_test (name,age) VALUES('eee',22)";
            int result = st.executeUpdate(sql);
            if(result > 0){
                System.out.println("添加成功");
            }
        }
  • 相关阅读:
    PID算法控制直流电机笔记
    HAL库直流电机编码测速(L298N驱动)笔记
    HAl库控制L298N直流电机旋转笔记
    MQTT介绍与使用(转载)
    STM32中STD、HAL、LL库比较
    rpm检验是否被改动过
    find命令 参数
    会话管理测试时的注意点
    无权限修改用户组权限的状况一
    burpsuite + sqlmap 日志导出批量扫描
  • 原文地址:https://www.cnblogs.com/zhuwenxia/p/9686701.html
Copyright © 2011-2022 走看看