windowFrames.cs

    @Test
    public void windowFrames() {
        driver.navigate().to("https://the-internet.herokuapp.com/windows");
        JavascriptExecutor js = (JavascriptExecutor) driver;
        js.executeScript(("window.open('https://the-internet.herokuapp.com/windows/new')"));

        String originalWindow = driver.getWindowHandle();
        Set handles = driver.getWindowHandles();
        handles.remove(originalWindow);

        String nextWindow = String.valueOf(handles.iterator().next());

        driver.switchTo().window(nextWindow);
        Assert.assertEquals("New Window", driver.getTitle());

        driver.close();
        driver.switchTo().window(originalWindow);
        Assert.assertEquals("The Internet", driver.getTitle());
    }