title: Get the key and value of Map that is used Inside another Map (JAVA)
body: <p>I am using a map inside another map, The key of the outer map is Integer and the value is another Map. I get the values as expected but I don't know how to get the key and value of teh inner map. 
  Here is the code</p>
  
  <pre><code>Map&lt;Integer, Map&lt;Integer, Integer&gt;&gt; cellsMap = new HashMap&lt;Integer, Map&lt;Integer, Integer&gt;&gt;();
  Map&lt;Integer , Integer&gt; bandForCell = cellsMap.get(band_number);
      if (bandForCell == null) 
          bandForCell = new HashMap&lt;Integer, Integer&gt;();
      bandForCell.put(erfcn, cell_found);
      cellsMap.put(band_number, bandForCell);
  
    csv.writeCells((Map&lt;Integer, Map&lt;Integer, Integer&gt;&gt;) cellsMap);
  
  public void writeCells (Map&lt;Integer, Map&lt;Integer, Integer&gt;&gt; cellsMap ) throws IOException
  {
      for (Map.Entry&lt;Integer, Map&lt;Integer, Integer&gt;&gt; entry : cellsMap.entrySet()) {
          System.out.println("Key: " + entry.getKey() + ". Value: " + entry.getValue() + "\n");
      }           
  }
  </code></pre>
  
  <p>Out put of my Map</p>
  
  <pre><code>Key: 20 Value: {6331=0, 6330=1, 6329=1, 6328=0, 6335=1, 6437=0, 6436=1}
  </code></pre>
  
  <p>The value in the above output is another map.
  How can I get the key and value of the inner map from the value of the outer map?</p>
  
  <p>Like Keys of inner map = 6331, 6330, 6329 ....
  and values of inner map = 0 , 1 , 1 , 0 ... </p>
  
  <p>Thanks</p>