https://mksiva.com/tags/null-key/ Recent content in Null Key on Siva Kalidasan Hugo en-us Fri, 23 Sep 2016 00:00:00 +0000 https://mksiva.com/tech/dealing-with-java-and-json-conversion/ Fri, 23 Sep 2016 00:00:00 +0000 https://mksiva.com/tech/dealing-with-java-and-json-conversion/ <p>When you are trying to convert any java object to json, you may run in to this problem.</p> <pre tabindex="0"><code>com.fasterxml.jackson.core.JsonGenerationException: Null key for a Map not allowed in JSON (use a converting NullKeySerializer?) </code></pre><p>This is due to null key in the map of objects (or collection of objects). JsonGenerator cannot serialize the null key into json.</p> <h2 id="ignore-null-values-in-the-map">Ignore &rsquo;null&rsquo; values in the map</h2> <p>So we can ignore &rsquo;null&rsquo; key and values from the ObjectMapper by using:</p>