title: Java null String equals result
body: <p>Please help me how does the string.equals in java work with null value? Is there some problem with exceptions?
  Three cases:</p>
  
  <pre><code>boolean result1,result2, result3;
  
      //1st case
      String string1 = null;
      String string2 = null;
      result = string1.equals(string2);
      //2nd case
      String string1 = "something";
      String string2 = null;
      result2 = string1.equals(string2);
      //3rd case 
      String string1 = null;
      String string2 = "something";
      result3 = string1.equals(string2);
  </code></pre>
  
  <p>What the values of results are? I expect this values:</p>
  
  <blockquote>
    <p>result1 is true;<br>
    result2 is false;<br>
    result3 is false;</p>
  </blockquote>