title: java sendkeys Error keys should be a string
body: <p>I'm getting an error when trying to pass in a username and password to a form field using <code>sendKeys</code>.  Below is my User Class followed by my test class.  Does anyone know why the application is not passing a string?</p>
  
  <blockquote>
    <p>org.openqa.selenium.WebDriverException: unknown error: keys should be a string</p>
  </blockquote>
  
  <pre><code>public class User {
      public static String username;
      public static String password;
  
  
      public User() {
          this.username = "username";
          this.password = "password";
      }
  
      public String getUsername(){
          return username;
      }
  
      public String getPassword(){
          return password;
      }
  
  }
  
  @Test
  public void starWebDriver()  {
      driver.get(domainURL.getURL());
      WebElement userInputBox, passInputBox;
      userInputBox = driver.findElement(By.xpath("//input[@name='email']"));
      passInputBox = driver.findElement(By.xpath("//input[@name='password']"));
      System.out.println("before sending keys");
      userInputBox.sendKeys(User.username);
  }
  </code></pre>