What exactly does ime() in selenium do?

Question

driverInstanceName.manage().ime().getActiveEngine()
driverInstanceName.manage().ime().activateEngine(engine)

getting exceptions like below,

org.openqa.selenium.WebDriverException: 
unimplemented command: session/3f83e50445b7c179249aada785c8e910/ime/activate
Command duration or timeout: 2 milliseconds

Understood that it is related to inputting data but not sure how it is relevant in selenium, tried finding the answer in many forums but to no avail.

Answer 1

Got interested to learn more about ime() method after reading this question and punched out google searches around this:

IME - stands for Input Method Engine. Currently seems like this is only supported in Linux platform and Firefox browser.

When working with Chinese/Japanese or multi-byte characters that needs to input by Selenium in linux, you have to use input framework like IBus and the engines implemented on IBus like anthy (Japanese), pinyin (Chinese).

The following code example is taken from Selenium's I18NTest.java, which looks for anthy engine to input Japanese characters on a linux machine.

  @NeedsFreshDriver
  @Ignore(value = {IE, CHROME, FIREFOX},
          reason = "Not implemented on anything other than Firefox/Linux at the moment.")
  @NotYetImplemented(HTMLUNIT)
  @Test
  public void testShouldBeAbleToActivateIMEEngine() throws InterruptedException {
    assumeTrue("IME is supported on Linux only.",
               TestUtilities.getEffectivePlatform().is(Platform.LINUX));

    driver.get(pages.formPage);

    WebElement input = driver.findElement(By.id("working"));

    // Activate IME. By default, this keycode activates IBus input for Japanese.
    WebDriver.ImeHandler ime = driver.manage().ime();

    List<String> engines = ime.getAvailableEngines();
    String desiredEngine = "anthy";

    if (!engines.contains(desiredEngine)) {
      System.out.println("Desired engine " + desiredEngine + " not available, skipping test.");
      return;
    }

    ime.activateEngine(desiredEngine);

    int totalWaits = 0;
    while (!ime.isActivated() && (totalWaits < 10)) {
      Thread.sleep(500);
      totalWaits++;
    }
    assertTrue("IME Engine should be activated.", ime.isActivated());
    assertEquals(desiredEngine, ime.getActiveEngine());

    // Send the Romaji for "Tokyo". The space at the end instructs the IME to convert the word.
    input.sendKeys("toukyou ");
    input.sendKeys(Keys.ENTER);

    String elementValue = input.getAttribute("value");

    ime.deactivate();
    assertFalse("IME engine should be off.", ime.isActivated());

    // IME is not present. Don't fail because of that. But it should have the Romaji value
    // instead.
    assertTrue("The elemnt's value should either remain in Romaji or be converted properly."
        + " It was:" + elementValue, elementValue.equals(tokyo));
  }

Caution: My answer may give a fair idea about the ime(), still more insights can be improved by selenium committers, as I see this feature is not in widespread use and also has limited support (only in Linux).