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我正在使用olingo使用OData v4协议处理其余的系统。我被堆叠在导航时心中已经得到了让我们说：如何在OData 4中实现三重或更多分段导航4
Company.svc/Departaments（X）/雇员（X）/ BussinesTrips
在Olingo的教程存在这样的情况是2个段导航的示例。第一部分是UriResourceEntitySet，第二部分是UriResourceNavigation。 在这个例子中，这两个（尤其是entitySet）是从存储中获取相关实体集合的方法中的参数。
在我的例子中有Company.svc/UriResourceEntitySet/UriResourceNavigation/UriResourceNavigation，我可以从UriInfo参数说。
我不知道该怎么做。我应该改变方法或以某种方式强制penulimate段为EntitySet。
感谢您的支持，我即将等待回拨。
@Override
public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat)
throws ODataApplicationException, ODataLibraryException {
String lastUri = "lastUriResource";
String sourceNavigationUri = "sourceUriResource";
EdmEntitySet responseEntitySet = null;
EntityCollection responseEntityCollection = null;
List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
UriResource uriResource = resourcePaths.get(0);
if (!(uriResource instanceof UriResourceEntitySet)) {
throw new ODataApplicationException("Only EntitySet is supported", HttpStatusCode.NOT_IMPLEMENTED.getStatusCode(), Locale.ENGLISH);
}
UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) uriResource;
EdmEntitySet startEntitySet = uriResourceEntitySet.getEntitySet();
if (resourcePaths.size() == 1) {
responseEntitySet = startEntitySet;
responseEntityCollection = storage.readEntitySetData(responseEntitySet);
} else {
startEntitySet = Util.getNavigationTargetEntitySet(uriInfo);
HashMap<String, UriResource> uriResourceHashMap = Util.getLastNavigationAndItsSource(uriInfo);
UriResource lastUriResource = uriResourceHashMap.get(lastUri);
UriResource sourceUriResource = uriResourceHashMap.get(sourceNavigationUri);
EdmNavigationProperty edmNavigationProperty = null;
if (!(lastUriResource instanceof UriResourceNavigation)) {
throw new ODataApplicationException("Only navigation is supported", HttpStatusCode.NOT_IMPLEMENTED.getStatusCode(), Locale.ENGLISH);
}
edmNavigationProperty = ((UriResourceNavigation) lastUriResource).getProperty();
if (!(sourceUriResource instanceof UriResourceEntitySet)) {
throw new ODataApplicationException("Only Entity Set is supported", HttpStatusCode.NOT_IMPLEMENTED.getStatusCode(), Locale.ENGLISH);
}
uriResourceEntitySet = (UriResourceEntitySet) sourceUriResource;
startEntitySet = uriResourceEntitySet.getEntitySet();
responseEntitySet = Util.getNavigationTargetEntitySet(uriInfo);
EdmEntityType targetEntityType = edmNavigationProperty.getType();
List<UriParameter> keyParameters = uriResourceEntitySet.getKeyPredicates();
Entity sourceEntity = storage.readEntityData(startEntitySet, keyParameters);
if (sourceEntity == null) {
throw new ODataApplicationException("Entity not found", HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ROOT);
}
responseEntityCollection = storage.getRelatedEntityCollection(sourceEntity, targetEntityType);
}
ContextURL contextUrl = ContextURL.with().entitySet(responseEntitySet).build();
final String id = request.getRawBaseUri() + "/" + responseEntitySet.getName();
EntityCollectionSerializerOptions options = EntityCollectionSerializerOptions.with().id(id).contextURL(contextUrl).build();
EdmEntityType edmEntityType = responseEntitySet.getEntityType();
ODataSerializer serializer = odata.createSerializer(responseFormat);
SerializerResult serializerResult = serializer.entityCollection(serviceMetaData, edmEntityType, responseEntityCollection, options);
InputStream inputStream = serializerResult.getContent();
response.setContent(inputStream);
response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
response.setStatusCode(HttpStatusCode.OK.getStatusCode());
}
}