title: Bound mismatch for java Collections sorting
body: <p>Hi need Help regarding java collection sorting. It gives me this error:</p>
  
  <pre><code>Bound mismatch: The generic method sort(List&lt;T&gt;) of type Collections is not applicable for the arguments (List&lt;WifiSSID&gt;). 
  The inferred type WifiSSID is not a valid substitute for the bounded parameter &lt;T extends Comparable&lt;? super T&gt;&gt;
  </code></pre>
  
  <p>My code looks like:</p>
  
  <pre><code>public class WifiSSID {
  
      public String SSIS;
      public double id;
  }
  
  
   public class ScanFilterWifiList {
  
      public ScanFilterWifiList(List&lt;WifiSSID&gt; wifiList) {
          Collections.sort(wifiList);
             //Collections.sort(wifiList, new SortSSIDByid()); tried this also.
      }
  }
  interface Comparator&lt;WifiSSID&gt;
  {
      int compare(WifiSSID obj1, WifiSSID obj2);
  }
  
  class SortSSIDByid implements Comparator&lt;WifiSSID&gt;
  {
      @Override
      public int compare(WifiSSID ssid1, WifiSSID ssid2) 
      {
          int value = 0; 
          if (ssid1.id &gt; ssid2.id) 
              value = 1; 
          else if (ssid1.id &lt; ssid2.id) 
              value = -1; 
          else if (ssid1.id == ssid2.id) 
              value = 0; 
          return value; 
       }
  }
  </code></pre>
  
  <p>Am I doing anything wrong?</p>