title: What is the equivalent to .contains for string buffers
body: <p>What is an equivalent way to use .contains when using a StringBuffer?</p>
  
  <p>For example, with a String you could write </p>
  
  <pre><code>String word = "word";
  
  if(word.contains("w") {
  //Does something
  }
  </code></pre>
  
  <p>But if you change word into a StringBuffer, you get an error that reads: "The method contains(String) is undefined for the type 
  StringBuffer"</p>
  
  <p>How would I be able to code the same line but with word as a StringBuffer?</p>