title: How to remove the key/value pair from a List<Map<String, Object>>
body: <p>I have a <code>List&lt;Map&lt;String, Object&gt;&gt;</code> like the following.</p>
  
  <pre><code>[{a=1, b=Kanji, c=null, d=Alphabet}]
  </code></pre>
  
  <p>I already know "c" key sometimes has the value = <code>null</code>, so I want to delete "c" key from <code>List&lt;Map&lt;String, Object&gt;&gt;</code> if that is the case.</p>
  
  <p>So I want the result like if "c" key has the value = "null" or empty</p>
  
  <p><code>[{a=1, b=Kanji, d=Alphabet}]</code></p>
  
  <p>So I tried</p>
  
  <pre><code>List&lt;Map&lt;String, Object&gt;&gt; list = ....(procedure to get the  [{a=1, b=Kanji, c=null, d=Alphabet}] from sql)
  
  for (Map&lt;String, Object&gt; child : list) {
      Object value = child.get("c");
        if(value == null || value == "") {
          list.remove("c");
        }
  }
  </code></pre>
  
  <p>But the List still shows</p>
  
  <pre><code>[{a=1, b=Kanji, c=null, d=Alphabet}]
  </code></pre>
  
  <p>How can I remove the value "c" from the list?</p>
  
  <p>I want to get the consequence as <code>List&lt;Map&lt;String, Object&gt;&gt;</code>.</p>