if(driver.findElement(By.xpath("/html/body/div[2]/div/div/div/div/div/div/table/tbody/tr[6]/td[2]")).isDisplayed())
{    
    driver.findElement(By.linkText("logout")).getAttribute("href");          
} else {          
    driver.findElement(By.xpath("/html/body/div/div/div/a[2]")).click();
}