title: Overloading + in case of a string literal to another is different than overloading a reference with a string literal
body: <p>In java for below code:- </p>
  
  <pre><code>s1="ab"
  s2="a"
  s1=="a"+"b" 
  s1==s2+"b" 
  </code></pre>
  
  <p>The first comparison returs true and second comparison returns flase. Why so?</p>
  
  <p><strong>Note:- both results in "ab" string only</strong></p>