How to verify element present or visible in selenium 2 (Selenium WebDriver)

I used java print statements for easy understanding.

1. To check Element Present:

   if(driver.findElements(By.xpath("value")).size() != 0){
   System.out.println("Element is Present");
   }else{
   System.out.println("Element is Absent");
   }
   

   Or

   if(driver.findElement(By.xpath("value"))!= null){
   System.out.println("Element is Present");
   }else{
   System.out.println("Element is Absent");
   }
   

2. To check Visible:

   if( driver.findElement(By.cssSelector("a > font")).isDisplayed()){
   System.out.println("Element is Visible");
   }else{
   System.out.println("Element is InVisible");
   }
   

3. To check Enable:

   if( driver.findElement(By.cssSelector("a > font")).isEnabled()){
   System.out.println("Element is Enable");
   }else{
   System.out.println("Element is Disabled");
   }
   

4. To check text present

   if(driver.getPageSource().contains("Text to check")){
   System.out.println("Text is present");
   }else{
   System.out.println("Text is absent");
   }