title: get Count of distinct value for multiple column from Dataframe using Spark and Java8
body: <p>I want to get Count of distinct value for multiple column from Dataframe using Spark and Java8</p>
  
  <p>Input DataFrame  - Need to write code for Dynamic columns - Columns may be added later</p>
  
  <pre><code>+----+----+----+
  |Col1|Col2|Col3|
  +----+----+----+
  |A1|Y|B2|Y|C3|Y|
  |A1|Y|B2|N|C3|Y|
  |A1|Y|B2|Y|C3|N|
  +----+----+----+
  </code></pre>
  
  <p>Output DateFrame</p>
  
  <pre><code>+--------+---------------------+--------------------+
  |Col1    | Col2                | Col3               |
  +--------+---------------------+--------------------+
  |A1|Y - 3| B2|Y - 2 &amp; B2|N - 1 | C3|Y - 3 &amp; C3|N -1 |
  +----+----+----+----+----+----+----+----+----+------+
  </code></pre>