code: private int readCRS(JsonParser jp) throws IOException, SQLException {
          int srid = 0;
          jp.nextToken(); //START_OBJECT {
          jp.nextToken();// crs type
          jp.nextToken(); // crs name
          String firstField = jp.getText();
          if(firstField.equalsIgnoreCase(GeoJsonField.NAME)){
              jp.nextToken(); // crs properties
              jp.nextToken(); //START_OBJECT {
              jp.nextToken(); // crs name
              jp.nextToken(); // crs value
              String crsURI = jp.getText();
              String[] split = crsURI.toLowerCase().split(GeoJsonField.CRS_URN_EPSG);
              if (split != null) {
                  srid = Integer.valueOf(split[1]);
              } else {
                  log.warn("The CRS URN " + crsURI + " is not supported.");
              }
              jp.nextToken(); //END_OBJECT }
              jp.nextToken(); //END_OBJECT }
              jp.nextToken(); //Go to features
          }        
          else if (firstField.equalsIgnoreCase(GeoJsonField.LINK)) {
              log.warn("Linked CRS is not supported.");
              jp.nextToken();
              jp.nextToken();
              jp.nextToken(); //END_OBJECT }
              jp.nextToken(); //END_OBJECT }
              jp.nextToken(); //Go to features
          }
          else{
              throw new SQLException("Malformed GeoJSON CRS element.");
          }
          
          return srid;
      }
docs: Reads the CRS element and return the database SRID.
  
  Parsed syntax:
  
  "crs":{
  "type":"name",
  "properties":
  {"name":"urn:ogc:def:crs:EPSG::4326"
  }
  }
  
  @param jp
  @return