title: How can I LowerCase all the HashMap's values?
body: <p>I have a <code>Map&lt;String,Map&lt;String,String&gt;&gt;</code> where I'd like to LowerCase every key and value. With the following code, I'm able to do so but the structure of my data changes. How can I possibly fix this?</p>
  
  <pre><code>for (Map.Entry&lt;String, Map&lt;String, String&gt;&gt; t : list.entrySet()) {
      for (Map.Entry&lt;String, String&gt; e : t.getValue().entrySet()) {
          lowerCaseList1.put(t.getKey().toLowerCase().trim(), lowerCaseList2.put(e.getValue().toLowerCase().trim(), e.getKey().toLowerCase().trim()));
      }
  }
  </code></pre>