title: GeoJson Jackson - parse JSON to Java object fails
body: <p>I am working on parsing a GeoJSON file into Java POJO classes.
  I have found the GeoJSON Jackson library which seems to be exactly the same as I need.</p>
  <p><a href="https://github.com/opendatalab-de/geojson-jackson" rel="nofollow noreferrer">https://github.com/opendatalab-de/geojson-jackson</a></p>
  <p>I have a JSON like the following:</p>
  <pre><code>    {
    &quot;type&quot;: &quot;FeatureCollection&quot;,
    &quot;features&quot;: [
      {
        &quot;type&quot;: &quot;Feature&quot;,
        &quot;properties&quot;: {
          &quot;lfdNr&quot;: 1,
          &quot;betriebsNummer&quot;: 33,
          &quot;nummer&quot;: 4,
          &quot;bezeichnung&quot;: &quot;TERST&quot;,
          &quot;kng&quot;: 61062323,
          &quot;nArtCode&quot;: &quot;A&quot;,
          &quot;nArtB&quot;: &quot;ACKERLAND&quot;,
          &quot;flaeche&quot;: 4.0748
        },
        &quot;geometry&quot;: {
          &quot;type&quot;: &quot;Polygon&quot;,
          &quot;coordinates&quot;: [
            [
              [
                15.8867118536754,
                48.4004384452486
              ],
              [
                15.884483831836,
                48.3981983444393
              ],
              [
                15.8847389374202,
                48.3991957290405
              ],
              [
                15.8853143451339,
                48.3991585954555
              ],
              [
                15.8851662097189,
                48.398462039698
              ],
              ....
            ]
          ]
        }
      }
    ]
  }
  </code></pre>
  <p>I wish to use it as a FeatureCollection java object:</p>
  <pre><code>objectMapper.readValue(json, FeatureCollection.class);
  </code></pre>
  <p>I get the following:</p>
  <pre><code>    com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct 
      instance of `org.geojson.GeoJsonObject` 
  (no Creators, like default constructor, exist): abstract types either need to be mapped to concrete types, 
  have custom deserializer, or contain additional type information
   at [Source: (String)&quot;{&quot;type&quot;:&quot;FeatureCollection&quot;,&quot;features&quot;:[{&quot;type&quot;:&quot;Feature&quot;,&quot;properties&quot;:{&quot;lfdNr&quot;:1,&quot;betriebsNummer&quot;:10086722,&quot;nummer&quot;:4,&quot;bezeichnung&quot;:&quot;TERST&quot;,&quot;fskennung&quot;:61062323,&quot;nutzungsArtCode&quot;:&quot;A&quot;,&quot;nutzungsArtBezeichnung&quot;:&quot;ACKERLAND&quot;,&quot;flaeche&quot;:4.0748},&quot;geometry&quot;:{&quot;type&quot;:&quot;Polygon&quot;,&quot;coordinates&quot;:[[[15.8867118536754,48.4004384452486],[15.8829132747878,48.4002081767679],[&quot;[truncated 2362 chars]; line: 1, column: 251] 
   (through reference chain: org.geojson.FeatureCollection[&quot;features&quot;]-&gt;java.util.ArrayList[0]-&gt;org.geojson.Feature[&quot;geometry&quot;])
  </code></pre>
  <p>I assume it is because the class Geometry a generic type is:</p>
  <pre><code>public abstract class Geometry&lt;T&gt; extends GeoJsonObject
  </code></pre>
  <p>I only operate with Polygons and Points.</p>
  <p>Any ides how can I get it working?</p>
  <p>Thanks a lot!</p>