title: Why the below code is not working (StringBuffer.toString !=null)
body: <p>I am new to String World ,</p>
  
  <p>I have coded as like below,</p>
  
  <pre><code>StringBuffer buffer=new StringBuffer();
  String addressLineOne=null;
  buffer.append(addreeLineOne);
  if(buffer.toString!=null)
  {
   system.out.println("Not NULL");
  }
  </code></pre>
  
  <p>Result:Not Null;
  (buffer.toString!=null)==true</p>
  
  <p>Eventhough I have append null to buffer ,I am not able to identify it by having NUll check,
  Code printing Not Null</p>
  
  <p>Why it so?</p>