Mapping Routes in React Router

// App.js
class App extends Component {
  render() {
    return (
      <BrowserRouter>
        <div>
          <Route exact path="/" component={HomePage} />
          <Route exact path="/Teachers" component={TeacherListPage} />
          <Route exact path="/Teachers/:teacherId" component={TeacherPage} />
          <Route exact path="/Teachers/:teacherId/Classes" component={TaughtClassesPage} />
        {/* And on and on for classes, grades, students, et cetera. */}
        </div>
      </BrowserRouter>
    );
  }
}

// You can declare this in `App.js`, but it might
// be better to move it to its own file.

const routes = [{
  path: '/',
  component: HomePage,
}, {
  path: '/Teachers',
  component: TeacherListPage,
}, {
  path: '/Teachers/:teacherId',
  component: TeacherPage,
}, {
  path: '/Teachers/:teacherId/Classes',
  component: TaughtClassesPage,
}, /* And so on. */];

class App extends Component {
  render() {
    const routeComponents = routes.map(({path, component}, key) => <Route exact path={path} component={component} key={key} />);
    return (
      <BrowserRouter>
        {routeComponents}
        </div>
      </BrowserRouter>
    );
  }
}