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");
        }
    }