title: Read CSV file with 3 columns into Datastream. JAVA Apache Flink
body: <p>I've been struggling for a while setting up a flink application that creates a <code>Datastream&lt;Tuple3&lt;Integer, java.sql.Time, Double&gt;&gt;</code> from a csv file. The columns in this file (columns <code>ID, dateTime and Result</code>) are all String but they should be converted to Integer, java.sql.Time and Double. The other thing I want is to create tumbling windows with data per day and average the values of the <code>result</code> column in that window. The problem is that I dont know the exact syntax for it. See my code below what I tried. The last part I have sum(2), but I want to calculate the average for the windows. I did not see in a function for this in the documentation. Do I need to write a method myself for this?</p>
  
  <pre><code>
  DataStream&lt;Tuple3&lt;String, java.sql.Time&gt;&gt; dataStream = env
                  .readfile(path)
                  .map()
                  .keyBy(0)
                  .timeWindow(Time.days(1));
  </code></pre>