private void readNavigationProperty()

in odata2-lib/odata-core/src/main/java/org/apache/olingo/odata2/core/ep/consumer/JsonEntryConsumer.java [275:386]
108 lines of code
18 McCabe index (conditional complexity)

  private void readNavigationProperty(final String navigationPropertyName) throws IOException, EntityProviderException,
      EdmException {
    NavigationPropertyInfo navigationPropertyInfo = eia.getNavigationPropertyInfo(navigationPropertyName);
    if (navigationPropertyInfo == null) {
      throw new EntityProviderException(EntityProviderException.ILLEGAL_ARGUMENT.addContent(navigationPropertyName));
    }

    JsonToken peek = reader.peek();
    if (peek == JsonToken.BEGIN_OBJECT) {
      reader.beginObject();
      String name = reader.nextName();
      if (FormatJson.DEFERRED.equals(name)) {
        reader.beginObject();
        String uri = reader.nextName();
        if (FormatJson.URI.equals(uri)) {
          String value = reader.nextString();
          entryMetadata.putAssociationUri(navigationPropertyInfo.getName(), value);
        } else {
          throw new EntityProviderException(EntityProviderException.ILLEGAL_ARGUMENT.addContent(uri));
        }
        reader.endObject();
      } else {
        EdmNavigationProperty navigationProperty =
            (EdmNavigationProperty) eia.getEntityType().getProperty(navigationPropertyName);
        EdmEntitySet inlineEntitySet = eia.getEntitySet().getRelatedEntitySet(navigationProperty);
        EntityInfoAggregator inlineEia = EntityInfoAggregator.create(inlineEntitySet);
        EntityProviderReadProperties inlineReadProperties;
        OnReadInlineContent callback = readProperties.getCallback();
        try {
          if (callback == null) {
            inlineReadProperties =
                EntityProviderReadProperties.init()
                    .mergeSemantic(readProperties.getMergeSemantic())
                    .isValidatingFacets(readProperties.isValidatingFacets())
                    .build();

          } else {
            inlineReadProperties = callback.receiveReadProperties(readProperties, navigationProperty);
          }

          if (navigationProperty.getMultiplicity() == EdmMultiplicity.MANY) {
            JsonFeedConsumer inlineConsumer = new JsonFeedConsumer(reader, inlineEia, inlineReadProperties);
            ODataFeed feed = inlineConsumer.readStartedInlineFeed(name);
            updateExpandSelectTree(navigationPropertyName, feed);
            if (callback == null) {
              properties.put(navigationPropertyName, feed);
              resultEntry.setContainsInlineEntry(true);
            } else {
              ReadFeedResult result = new ReadFeedResult(inlineReadProperties, navigationProperty, 
                  feed, entryMetadata.getId() != null ? entryMetadata.getId() : fetchParentIdInfo(eia, resultEntry));
              callback.handleReadFeed(result);
            }
          } else {
            JsonEntryConsumer inlineConsumer = new JsonEntryConsumer(reader, inlineEia, inlineReadProperties);
            ODataEntry entry = inlineConsumer.readInlineEntry(name);
            updateExpandSelectTree(navigationPropertyName, entry);
            if (callback == null) {
              properties.put(navigationPropertyName, entry);
              resultEntry.setContainsInlineEntry(true);
            } else {
              ReadEntryResult result = new ReadEntryResult(inlineReadProperties, navigationProperty, 
                  entry, entryMetadata.getId() != null ? entryMetadata.getId() : fetchParentIdInfo(eia, resultEntry));
              callback.handleReadEntry(result);
            }
          }

        } catch (ODataApplicationException e) {
          throw new EntityProviderException(EntityProviderException.EXCEPTION_OCCURRED.addContent(e.getClass()
              .getSimpleName()), e);
        }
      }
      reader.endObject();
    } else if (peek == JsonToken.NULL) {
      reader.nextNull();
    } else {
      final EdmNavigationProperty navigationProperty =
          (EdmNavigationProperty) eia.getEntityType().getProperty(navigationPropertyName);
      final EdmEntitySet inlineEntitySet = eia.getEntitySet().getRelatedEntitySet(navigationProperty);
      final EntityInfoAggregator inlineInfo = EntityInfoAggregator.create(inlineEntitySet);
      OnReadInlineContent callback = readProperties.getCallback();
      EntityProviderReadProperties inlineReadProperties;
      if (callback == null) {
        inlineReadProperties =
            EntityProviderReadProperties.init()
                .mergeSemantic(readProperties.getMergeSemantic())
                .isValidatingFacets(readProperties.isValidatingFacets())
                .build();
      } else {
        try {
          inlineReadProperties = callback.receiveReadProperties(readProperties, navigationProperty);
        } catch (final ODataApplicationException e) {
          throw new EntityProviderException(EntityProviderException.EXCEPTION_OCCURRED.addContent(e.getClass()
              .getSimpleName()), e);
        }
      }
      ODataFeed feed = new JsonFeedConsumer(reader, inlineInfo, inlineReadProperties).readInlineFeedStandalone();
      updateExpandSelectTree(navigationPropertyName, feed);
      if (callback == null) {
        properties.put(navigationPropertyName, feed);
        resultEntry.setContainsInlineEntry(true);
      } else {
        ReadFeedResult result = new ReadFeedResult(inlineReadProperties, navigationProperty,
            feed, entryMetadata.getId() != null ? entryMetadata.getId() : fetchParentIdInfo(eia, resultEntry));
        try {
          callback.handleReadFeed(result);
        } catch (final ODataApplicationException e) {
          throw new EntityProviderException(EntityProviderException.EXCEPTION_OCCURRED.addContent(e.getClass()
              .getSimpleName()), e);
        }
      }
    }
  }