title: How to identify String is encoded with Base64
body: <p>I am encoding URL request parameters from string to Base64 string using encodeURIComponent() method and passing it to server.
  Server side in servlet filter i am decoding it from Base64 to string using java.util.Base64.</p>
  
  <p>I am not converting all the requests(request parameters). If the URL contains json request parameters than only I am encoding the request parameter.</p>
  
  <p>Here my problem is I want to check the request parameters is encoded or not.</p>
  
  <p>Can any one suggest me any method is available to identify request parameter is encoded or not.</p>