title: String comparison unexpected output
body: <p>In below program i am getting <strong>output</strong> as <strong>false</strong> .But as per my understanding when we add two temporary reference variable then result go inside constant pool which does not allow duplicates so we must have gotten <strong>output as true</strong> here but we are getting <strong>false as an output</strong>.Can somebody explain me reason behind this?</p>
  
  <pre><code>package com.lara;
  
  public class Man9 
  {
      public static void main(String[] args) 
      {
          String s1 = "ja";
          String s2 = "va";
          String s3 = "ja".concat("va");
          String s4 = "java";
          System.out.println(s3==s4);
      }
  }
  </code></pre>