Java Code Examples for org.apache.olingo.server.api.ODataResponse#setHeader()

@Override
public ODataResponse createDebugResponse(final DebugInformation debugInfo) {
  try {
    final List<DebugTab> parts = createParts(debugInfo);

    ODataResponse response = new ODataResponse();
    final String contentTypeString;
    final InputStream body;
    if (requestedFormat == DebugFormat.DOWNLOAD || requestedFormat == DebugFormat.HTML) {
      String title = debugInfo.getRequest() == null ?
          "V4 Service" : "V4 Service: " + debugInfo.getRequest().getRawODataPath();
      body = wrapInHtml(parts, title);
      contentTypeString = ContentType.TEXT_HTML.toContentTypeString();
    } else {
      // for JSON and also default response handling
      body = wrapInJson(parts);
      contentTypeString = ContentType.APPLICATION_JSON.toContentTypeString();
    }
    // for download add additional Content-Disposition header
    if (requestedFormat == DebugFormat.DOWNLOAD) {
      response.setHeader("Content-Disposition", "attachment; filename=OData-Response."
          + new Date().toString().replace(' ', '_').replace(':', '.') + ".html");
    }
    response.setStatusCode(HttpStatusCode.OK.getStatusCode());
    response.setHeader(HttpHeader.CONTENT_TYPE, contentTypeString);
    response.setContent(body);

    return response;
  } catch (IOException e) {
    // Should not happen. In case it does the library will deliver a default response. So no handling here.
    throw new ODataRuntimeException(e);
  }
}
 

public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat) throws ODataApplicationException, SerializerException {

		// 1st retrieve the requested EntitySet from the uriInfo (representation of the parsed URI)
		List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
		UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
		EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

		// 2nd: fetch the data from backend for this requested EntitySetName and deliver as EntitySet
		EntityCollection entityCollection = storage.readEntitySetData(edmEntitySet);

		// 3rd: create a serializer based on the requested format (json)
		ODataSerializer serializer = odata.createSerializer(responseFormat);

		// and serialize the content: transform from the EntitySet object to InputStream
		EdmEntityType edmEntityType = edmEntitySet.getEntityType();
		ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build();

		final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
		EntityCollectionSerializerOptions opts =
				EntityCollectionSerializerOptions.with().id(id).contextURL(contextUrl).build();
		SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, edmEntityType, entityCollection, opts);
		InputStream serializedContent = serializerResult.getContent();

		// 4th: configure the response object: set the body, headers and status code
		response.setContent(serializedContent);
		response.setStatusCode(HttpStatusCode.OK.getStatusCode());
		response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
	}
 

public void createEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo,
												 ContentType requestFormat, ContentType responseFormat)
			throws ODataApplicationException, DeserializerException, SerializerException {
	
	// 1. Retrieve the entity type from the URI 
	EdmEntitySet edmEntitySet = Util.getEdmEntitySet(uriInfo);
	EdmEntityType edmEntityType = edmEntitySet.getEntityType();

	// 2. create the data in backend 
	// 2.1. retrieve the payload from the POST request for the entity to create and deserialize it
	InputStream requestInputStream = request.getBody();
	ODataDeserializer deserializer = odata.createDeserializer(requestFormat);
	DeserializerResult result = deserializer.entity(requestInputStream, edmEntityType);
	Entity requestEntity = result.getEntity();
	// 2.2 do the creation in backend, which returns the newly created entity
	Entity createdEntity = null;
	
	try {
	  storage.beginTransaction();
	  createdEntity = storage.createEntityData(edmEntitySet, requestEntity, request.getRawBaseUri());
	  storage.commitTransaction();
	} catch( ODataApplicationException e ) {
	  storage.rollbackTransaction();
	  throw e;
	}
	  
	  // 3. serialize the response (we have to return the created entity)
	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build(); 
	EntitySerializerOptions options = EntitySerializerOptions.with().contextURL(contextUrl).build(); // expand and select currently not supported 
	
	ODataSerializer serializer = odata.createSerializer(responseFormat);
	SerializerResult serializedResponse = serializer.entity(serviceMetadata, edmEntityType, createdEntity, options);
	
	//4. configure the response object
	response.setContent(serializedResponse.getContent());
	response.setStatusCode(HttpStatusCode.CREATED.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

public void readEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat)
						throws ODataApplicationException, SerializerException {

	// 1. retrieve the Entity Type
	List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
	// Note: only in our example we can assume that the first segment is the EntitySet
	UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0);
	EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

	// 2. retrieve the data from backend
	List<UriParameter> keyPredicates = uriResourceEntitySet.getKeyPredicates();
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);

	// 3. serialize
	EdmEntityType entityType = edmEntitySet.getEntityType();

	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).suffix(ContextURL.Suffix.ENTITY).build();
 	// expand and select currently not supported
	EntitySerializerOptions options = EntitySerializerOptions.with().contextURL(contextUrl).build();

	ODataSerializer serializer = this.odata.createSerializer(responseFormat);
	SerializerResult serializerResult = serializer.entity(serviceMetadata, entityType, entity, options);
	InputStream entityStream = serializerResult.getContent();

	//4. configure the response object
	response.setContent(entityStream);
	response.setStatusCode(HttpStatusCode.OK.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat) throws ODataApplicationException, SerializerException {

    // 1st we have retrieve the requested EntitySet from the uriInfo object (representation of the parsed service URI)
    List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
    UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); // in our example, the first segment is the EntitySet
    EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

    // 2nd: fetch the data from backend for this requested EntitySetName // it has to be delivered as EntitySet object
    EntityCollection entitySet = getData(edmEntitySet);

    // 3rd: create a serializer based on the requested format (json)
    ODataSerializer serializer = odata.createSerializer(responseFormat);
    
    // 4th: Now serialize the content: transform from the EntitySet object to InputStream
    EdmEntityType edmEntityType = edmEntitySet.getEntityType();
    ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build();

    final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
    EntityCollectionSerializerOptions opts =
        EntityCollectionSerializerOptions.with().id(id).contextURL(contextUrl).build();
    SerializerResult serializedContent = serializer.entityCollection(serviceMetadata, edmEntityType, entitySet, opts);

    // Finally: configure the response object: set the body, headers and status code
    response.setContent(serializedContent.getContent());
    response.setStatusCode(HttpStatusCode.OK.getStatusCode());
    response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
  }
 

@Override
public void processBatch(final BatchFacade facade, final ODataRequest request, final ODataResponse response)
    throws ODataApplicationException, ODataLibraryException {
  
  // 1. Extract the boundary
  final String boundary = facade.extractBoundaryFromContentType(request.getHeader(HttpHeader.CONTENT_TYPE));
  
  // 2. Prepare the batch options
  final BatchOptions options = BatchOptions.with().rawBaseUri(request.getRawBaseUri())
                                                  .rawServiceResolutionUri(request.getRawServiceResolutionUri())
                                                  .build();
  
  // 3. Deserialize the batch request
  final List<BatchRequestPart> requestParts = odata.createFixedFormatDeserializer()
                                                   .parseBatchRequest(request.getBody(), boundary, options);
  
  // 4. Execute the batch request parts
  final List<ODataResponsePart> responseParts = new ArrayList<ODataResponsePart>();
  for (final BatchRequestPart part : requestParts) {
    responseParts.add(facade.handleBatchRequest(part));
  }

  // 5. Create a new boundary for the response
  final String responseBoundary = "batch_" + UUID.randomUUID().toString();

  // 6. Serialize the response content
  final InputStream responseContent = odata.createFixedFormatSerializer().batchResponse(responseParts, responseBoundary);

  // 7. Setup response
  response.setHeader(HttpHeader.CONTENT_TYPE, ContentType.MULTIPART_MIXED + ";boundary=" + responseBoundary);
  response.setContent(responseContent);
  response.setStatusCode(HttpStatusCode.ACCEPTED.getStatusCode());
}
 

public void createEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo,
												 ContentType requestFormat, ContentType responseFormat)
			throws ODataApplicationException, DeserializerException, SerializerException {
	
	// 1. Retrieve the entity type from the URI 
	EdmEntitySet edmEntitySet = Util.getEdmEntitySet(uriInfo);
	EdmEntityType edmEntityType = edmEntitySet.getEntityType();

	// 2. create the data in backend 
	// 2.1. retrieve the payload from the POST request for the entity to create and deserialize it
	InputStream requestInputStream = request.getBody();
	ODataDeserializer deserializer = this.odata.createDeserializer(requestFormat);
	DeserializerResult result = deserializer.entity(requestInputStream, edmEntityType);
	Entity requestEntity = result.getEntity();
	// 2.2 do the creation in backend, which returns the newly created entity
	Entity createdEntity = storage.createEntityData(edmEntitySet, requestEntity);
	
	// 3. serialize the response (we have to return the created entity)
	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build(); 
	EntitySerializerOptions options = EntitySerializerOptions.with().contextURL(contextUrl).build(); // expand and select currently not supported 
	
	ODataSerializer serializer = this.odata.createSerializer(responseFormat);
	SerializerResult serializedResponse = serializer.entity(serviceMetadata, edmEntityType, createdEntity, options);
	
	//4. configure the response object
	final String location = request.getRawBaseUri() + '/'
       + odata.createUriHelper().buildCanonicalURL(edmEntitySet, createdEntity);
	
	response.setHeader(HttpHeader.LOCATION, location);
	response.setContent(serializedResponse.getContent());
	response.setStatusCode(HttpStatusCode.CREATED.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

public void readEntity(ODataRequest request, ODataResponse response, UriInfo uriInfo, ContentType responseFormat)
     throws ODataApplicationException, SerializerException {
	
	// 1. retrieve the Entity Type 
	List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
	// Note: only in our example we can assume that the first segment is the EntitySet
	UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); 
	EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();
	
	// 2. retrieve the data from backend
	List<UriParameter> keyPredicates = uriResourceEntitySet.getKeyPredicates();
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);
	
	// 3. serialize
	EdmEntityType entityType = edmEntitySet.getEntityType();
	
	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).suffix(ContextURL.Suffix.ENTITY).build();
 	// expand and select currently not supported
	EntitySerializerOptions options = EntitySerializerOptions.with().contextURL(contextUrl).build();

	ODataSerializer serializer = this.odata.createSerializer(responseFormat);
	SerializerResult result = serializer.entity(serviceMetadata, entityType, entity, options);
	
	//4. configure the response object
	response.setContent(result.getContent());
	response.setStatusCode(HttpStatusCode.OK.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

@Test
public void changeSetResponse() throws Exception {
  List<ODataResponsePart> parts = new ArrayList<ODataResponsePart>();

  ODataResponse response = new ODataResponse();
  response.setHeader(HttpHeader.CONTENT_ID, "1");
  response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
  parts.add(new ODataResponsePart(Collections.singletonList(response), true));

  BatchResponseSerializer serializer = new BatchResponseSerializer();
  final InputStream content = serializer.serialize(parts, BOUNDARY);

  assertNotNull(content);

  final BatchLineReader reader = new BatchLineReader(content);
  final List<String> body = reader.toList();
  reader.close();

  int line = 0;
  assertEquals(14, body.size());
  assertEquals("--" + BOUNDARY + CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("Content-Type: multipart/mixed; boundary=changeset_"));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("Content-Type: application/http" + CRLF, body.get(line++));
  assertEquals("Content-Transfer-Encoding: binary" + CRLF, body.get(line++));
  assertEquals("Content-ID: 1" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("HTTP/1.1 204 No Content" + CRLF, body.get(line++));
  assertEquals("Content-Length: 0" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("--" + BOUNDARY + "--" + CRLF, body.get(line++));
}
 

public void readPrimitive(ODataRequest request, ODataResponse response, 
							UriInfo uriInfo, ContentType responseFormat) 
							throws ODataApplicationException, SerializerException {

	// 1. Retrieve info from URI
	// 1.1. retrieve the info about the requested entity set 
	List<UriResource> resourceParts = uriInfo.getUriResourceParts();
	// Note: only in our example we can rely that the first segment is the EntitySet
	UriResourceEntitySet uriEntityset = (UriResourceEntitySet) resourceParts.get(0); 
	EdmEntitySet edmEntitySet = uriEntityset.getEntitySet();
	// the key for the entity
	List<UriParameter> keyPredicates = uriEntityset.getKeyPredicates();
	
	// 1.2. retrieve the requested (Edm) property 
	UriResourceProperty uriProperty = (UriResourceProperty)resourceParts.get(resourceParts.size() -1); // the last segment is the Property
	EdmProperty edmProperty = uriProperty.getProperty();
	String edmPropertyName = edmProperty.getName();
	// in our example, we know we have only primitive types in our model
	EdmPrimitiveType edmPropertyType = (EdmPrimitiveType) edmProperty.getType(); 
	
	
	// 2. retrieve data from backend
	// 2.1. retrieve the entity data, for which the property has to be read
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);
	if (entity == null) { // Bad request
		throw new ODataApplicationException("Entity not found",
						HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	} 
	
	// 2.2. retrieve the property data from the entity
	Property property = entity.getProperty(edmPropertyName);
	if (property == null) {
		throw new ODataApplicationException("Property not found",
             HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	}		
	
	// 3. serialize
	Object value = property.getValue();
	if (value != null) {
		// 3.1. configure the serializer
		ODataSerializer serializer = odata.createSerializer(responseFormat);
		
		ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).navOrPropertyPath(edmPropertyName).build();
		PrimitiveSerializerOptions options = PrimitiveSerializerOptions.with().contextURL(contextUrl).build();
		// 3.2. serialize
		SerializerResult result = serializer.primitive(serviceMetadata, edmPropertyType, property, options);
		
		//4. configure the response object
		response.setContent(result.getContent());
		response.setStatusCode(HttpStatusCode.OK.getStatusCode());
		response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());		
	}else{
		// in case there's no value for the property, we can skip the serialization
		response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
	}
}
 

@Test
public void batchResponseUmlautsUtf8() throws Exception {
  List<ODataResponsePart> parts = new ArrayList<ODataResponsePart>();

  ODataResponse response = new ODataResponse();
  response.setStatusCode(HttpStatusCode.OK.getStatusCode());
  response.setHeader(HttpHeader.CONTENT_TYPE, ContentType.APPLICATION_JSON.toContentTypeString());
  response.setContent(IOUtils.toInputStream("{\"name\":\"Wälter Winter\"}" + CRLF));
  parts.add(new ODataResponsePart(Collections.singletonList(response), false));

  ODataResponse changeSetResponse = new ODataResponse();
  changeSetResponse.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
  changeSetResponse.setHeader(HttpHeader.CONTENT_ID, "1");
  parts.add(new ODataResponsePart(Collections.singletonList(changeSetResponse), true));

  BatchResponseSerializer serializer = new BatchResponseSerializer();
  final InputStream content = serializer.serialize(parts, BOUNDARY);
  assertNotNull(content);
  final BatchLineReader reader = new BatchLineReader(content);
  final List<String> body = reader.toList();
  reader.close();

  int line = 0;
  assertEquals(24, body.size());
  assertEquals("--" + BOUNDARY + CRLF, body.get(line++));
  assertEquals("Content-Type: application/http" + CRLF, body.get(line++));
  assertEquals("Content-Transfer-Encoding: binary" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("HTTP/1.1 200 OK" + CRLF, body.get(line++));
  assertEquals("Content-Type: application/json" + CRLF, body.get(line++));
  assertEquals("Content-Length: 27" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("{\"name\":\"Wälter Winter\"}" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("--" + BOUNDARY + CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("Content-Type: multipart/mixed; boundary=changeset_"));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("Content-Type: application/http" + CRLF, body.get(line++));
  assertEquals("Content-Transfer-Encoding: binary" + CRLF, body.get(line++));
  assertEquals("Content-ID: 1" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("HTTP/1.1 204 No Content" + CRLF, body.get(line++));
  assertEquals("Content-Length: 0" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("--" + BOUNDARY + "--" + CRLF, body.get(line++));
}
 

public void readPrimitive(ODataRequest request, ODataResponse response,
							UriInfo uriInfo, ContentType responseFormat)
							throws ODataApplicationException, SerializerException {

	// 1. Retrieve info from URI
	// 1.1. retrieve the info about the requested entity set
	List<UriResource> resourceParts = uriInfo.getUriResourceParts();
	// Note: only in our example we can rely that the first segment is the EntitySet
	UriResourceEntitySet uriEntityset = (UriResourceEntitySet) resourceParts.get(0);
	EdmEntitySet edmEntitySet = uriEntityset.getEntitySet();
	// the key for the entity
	List<UriParameter> keyPredicates = uriEntityset.getKeyPredicates();

	// 1.2. retrieve the requested (Edm) property
	// the last segment is the Property
	UriResourceProperty uriProperty = (UriResourceProperty)resourceParts.get(resourceParts.size() -1); 
	EdmProperty edmProperty = uriProperty.getProperty();
	String edmPropertyName = edmProperty.getName();
	// in our example, we know we have only primitive types in our model
	EdmPrimitiveType edmPropertyType = (EdmPrimitiveType) edmProperty.getType();


	// 2. retrieve data from backend
	// 2.1. retrieve the entity data, for which the property has to be read
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);
	if (entity == null) { // Bad request
		throw new ODataApplicationException("Entity not found", HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	}

	// 2.2. retrieve the property data from the entity
	Property property = entity.getProperty(edmPropertyName);
	if (property == null) {
		throw new ODataApplicationException("Property not found", HttpStatusCode.NOT_FOUND.getStatusCode(), 
		                                    Locale.ENGLISH);
	}

	// 3. serialize
	Object value = property.getValue();
	if (value != null) {
		// 3.1. configure the serializer
		ODataSerializer serializer = odata.createSerializer(responseFormat);

		ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).navOrPropertyPath(edmPropertyName).build();
		PrimitiveSerializerOptions options = PrimitiveSerializerOptions.with().contextURL(contextUrl).build();
		// 3.2. serialize
		SerializerResult serializerResult = serializer.primitive(serviceMetadata, edmPropertyType, property, options);
		InputStream propertyStream = serializerResult.getContent();

		//4. configure the response object
		response.setContent(propertyStream);
		response.setStatusCode(HttpStatusCode.OK.getStatusCode());
		response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
	} else {
		// in case there's no value for the property, we can skip the serialization
		response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
	}
}
 

public void readPrimitive(ODataRequest request, ODataResponse response, 
							UriInfo uriInfo, ContentType responseFormat) 
							throws ODataApplicationException, SerializerException {

	// 1. Retrieve info from URI
	// 1.1. retrieve the info about the requested entity set 
	List<UriResource> resourceParts = uriInfo.getUriResourceParts();
	// Note: only in our example we can rely that the first segment is the EntitySet
	UriResourceEntitySet uriEntityset = (UriResourceEntitySet) resourceParts.get(0); 
	EdmEntitySet edmEntitySet = uriEntityset.getEntitySet();
	// the key for the entity
	List<UriParameter> keyPredicates = uriEntityset.getKeyPredicates();
	
	// 1.2. retrieve the requested (Edm) property 
	UriResourceProperty uriProperty = (UriResourceProperty)resourceParts.get(resourceParts.size() -1); // the last segment is the Property
	EdmProperty edmProperty = uriProperty.getProperty();
	String edmPropertyName = edmProperty.getName();
	// in our example, we know we have only primitive types in our model
	EdmPrimitiveType edmPropertyType = (EdmPrimitiveType) edmProperty.getType(); 
	
	
	// 2. retrieve data from backend
	// 2.1. retrieve the entity data, for which the property has to be read
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);
	if (entity == null) { // Bad request
		throw new ODataApplicationException("Entity not found",
						HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	} 
	
	// 2.2. retrieve the property data from the entity
	Property property = entity.getProperty(edmPropertyName);
	if (property == null) {
		throw new ODataApplicationException("Property not found",
             HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	}		
	
	// 3. serialize
	Object value = property.getValue();
	if (value != null) {
		// 3.1. configure the serializer
		ODataSerializer serializer = odata.createSerializer(responseFormat);
		
		ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).navOrPropertyPath(edmPropertyName).build();
		PrimitiveSerializerOptions options = PrimitiveSerializerOptions.with().contextURL(contextUrl).build();
		// 3.2. serialize
		SerializerResult result = serializer.primitive(serviceMetadata, edmPropertyType, property, options);
		
		//4. configure the response object
		response.setContent(result.getContent());
		response.setStatusCode(HttpStatusCode.OK.getStatusCode());
		response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());		
	}else{
		// in case there's no value for the property, we can skip the serialization
		response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
	}
}
 

public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, 
    ContentType responseFormat) throws ODataApplicationException, SerializerException {

	// 1st retrieve the requested EntitySet from the uriInfo (representation of the parsed URI)
	List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
	// in our example, the first segment is the EntitySet
	UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); 
	EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

	// 2nd: fetch the data from backend for this requested EntitySetName and deliver as EntitySet
	EntityCollection entityCollection = storage.readEntitySetData(edmEntitySet);
	List<Entity> entityList = entityCollection.getEntities();
	
	// 3rd apply $orderby
	OrderByOption orderByOption = uriInfo.getOrderByOption();
	if (orderByOption != null) {
		List<OrderByItem> orderItemList = orderByOption.getOrders();
		final OrderByItem orderByItem = orderItemList.get(0); // in our example we support only one
		Expression expression = orderByItem.getExpression();
		if(expression instanceof Member){
			UriInfoResource resourcePath = ((Member)expression).getResourcePath();
			UriResource uriResource = resourcePath.getUriResourceParts().get(0);
			if (uriResource instanceof UriResourcePrimitiveProperty) {
				EdmProperty edmProperty = ((UriResourcePrimitiveProperty)uriResource).getProperty();
				final String sortPropertyName = edmProperty.getName();

				// do the sorting for the list of entities  
				Collections.sort(entityList, new Comparator<Entity>() {

					// we delegate the sorting to the native sorter of Integer and String
					public int compare(Entity entity1, Entity entity2) {
						int compareResult = 0;

						if(sortPropertyName.equals("ID")){
							Integer integer1 = (Integer) entity1.getProperty(sortPropertyName).getValue();
							Integer integer2 = (Integer) entity2.getProperty(sortPropertyName).getValue();
							
							compareResult = integer1.compareTo(integer2);
						}else{
							String propertyValue1 = (String) entity1.getProperty(sortPropertyName).getValue();
							String propertyValue2 = (String) entity2.getProperty(sortPropertyName).getValue();
							
							compareResult = propertyValue1.compareTo(propertyValue2);
						}

						// if 'desc' is specified in the URI, change the order of the list 
						if(orderByItem.isDescending()){
							return - compareResult; // just convert the result to negative value to change the order
						}
						
						return compareResult;
					}
				});
			}
		}
	}
	
	
	// 4th: create a serializer based on the requested format (json)
	ODataSerializer serializer = odata.createSerializer(responseFormat);

	// and serialize the content: transform from the EntitySet object to InputStream
	EdmEntityType edmEntityType = edmEntitySet.getEntityType();
	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build();

	final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
	EntityCollectionSerializerOptions opts =
			EntityCollectionSerializerOptions.with().id(id).contextURL(contextUrl).build();
   SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, edmEntityType, 
                                                                   entityCollection, opts);
	InputStream serializedContent = serializerResult.getContent();

	// 5th: configure the response object: set the body, headers and status code
	response.setContent(serializedContent);
	response.setStatusCode(HttpStatusCode.OK.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

public void readPrimitive(ODataRequest request, ODataResponse response,
							UriInfo uriInfo, ContentType responseFormat)
							throws ODataApplicationException, SerializerException {

	// 1. Retrieve info from URI
	// 1.1. retrieve the info about the requested entity set
	List<UriResource> resourceParts = uriInfo.getUriResourceParts();
	// Note: only in our example we can rely that the first segment is the EntitySet
	UriResourceEntitySet uriEntityset = (UriResourceEntitySet) resourceParts.get(0);
	EdmEntitySet edmEntitySet = uriEntityset.getEntitySet();
	// the key for the entity
	List<UriParameter> keyPredicates = uriEntityset.getKeyPredicates();

	// 1.2. retrieve the requested (Edm) property
	UriResourceProperty uriProperty = (UriResourceProperty)resourceParts.get(resourceParts.size() -1); // the last segment is the Property
	EdmProperty edmProperty = uriProperty.getProperty();
	String edmPropertyName = edmProperty.getName();
	// in our example, we know we have only primitive types in our model
	EdmPrimitiveType edmPropertyType = (EdmPrimitiveType) edmProperty.getType();


	// 2. retrieve data from backend
	// 2.1. retrieve the entity data, for which the property has to be read
	Entity entity = storage.readEntityData(edmEntitySet, keyPredicates);
	if (entity == null) { // Bad request
		throw new ODataApplicationException("Entity not found", HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	}

	// 2.2. retrieve the property data from the entity
	Property property = entity.getProperty(edmPropertyName);
	if (property == null) {
		throw new ODataApplicationException("Property not found", HttpStatusCode.NOT_FOUND.getStatusCode(), Locale.ENGLISH);
	}

	// 3. serialize
	Object value = property.getValue();
	if (value != null) {
		// 3.1. configure the serializer
		ODataSerializer serializer = odata.createSerializer(responseFormat);

		ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).navOrPropertyPath(edmPropertyName).build();
		PrimitiveSerializerOptions options = PrimitiveSerializerOptions.with().contextURL(contextUrl).build();
		// 3.2. serialize
		SerializerResult serializerResult = serializer.primitive(serviceMetadata, edmPropertyType, property, options);
		InputStream propertyStream = serializerResult.getContent();

		//4. configure the response object
		response.setContent(propertyStream);
		response.setStatusCode(HttpStatusCode.OK.getStatusCode());
		response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
	} else {
		// in case there's no value for the property, we can skip the serialization
		response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
	}
}
 

@Override
public void processActionComplexCollection(final ODataRequest request, ODataResponse response,
    final UriInfo uriInfo, final ContentType requestFormat, final ContentType responseFormat)
    throws ODataApplicationException, ODataLibraryException {
  EdmAction action = null;
  Map<String, Parameter> parameters = null;
  Property property = null;
  final List<UriResource> resourcePaths = uriInfo.asUriInfoResource().getUriResourceParts();
  if (resourcePaths.size() > 1) {
    if (resourcePaths.get(0) instanceof UriResourceEntitySet) {
      UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0);
      EdmEntitySet entitySet = uriResourceEntitySet.getEntitySet();
      action = ((UriResourceAction) resourcePaths.get(resourcePaths.size() - 1))
          .getAction();
      parameters = readParameters(action, request.getBody(), requestFormat);
      property =
          dataProvider.processBoundActionComplexCollection(action.getName(), parameters, entitySet, 
              uriResourceEntitySet.getKeyPredicates());
    }
  } else {
    action = ((UriResourceAction) resourcePaths.get(0))
        .getAction();
    parameters = readParameters(action, request.getBody(), requestFormat);
    property =
        dataProvider.processActionComplexCollection(action.getName(), parameters);
  }
  
  if (property == null || property.isNull()) {
    // Collection Propertys must never be null
    throw new ODataApplicationException("The action could not be executed.",
        HttpStatusCode.INTERNAL_SERVER_ERROR.getStatusCode(), Locale.ROOT);
  } else if (property.asCollection().contains(null) && !action.getReturnType().isNullable()) {
    // Not nullable return type but array contains a null value
    throw new ODataApplicationException("The action could not be executed.",
        HttpStatusCode.INTERNAL_SERVER_ERROR.getStatusCode(), Locale.ROOT);
  }
  final Return returnPreference = odata.createPreferences(request.getHeaders(HttpHeader.PREFER)).getReturn();
  if (returnPreference == null || returnPreference == Return.REPRESENTATION) {
    final EdmComplexType type = (EdmComplexType) action.getReturnType().getType();
    final ContextURL contextURL = ContextURL.with().type(type).asCollection().build();
    final ComplexSerializerOptions options = ComplexSerializerOptions.with().contextURL(contextURL).build();
    final SerializerResult result =
        odata.createSerializer(responseFormat).complexCollection(serviceMetadata, type, property, options);
    response.setContent(result.getContent());
    response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
    response.setStatusCode(HttpStatusCode.OK.getStatusCode());
  } else {
    response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
  }
  if (returnPreference != null) {
    response.setHeader(HttpHeader.PREFERENCE_APPLIED,
        PreferencesApplied.with().returnRepresentation(returnPreference).build().toValueString());
  }
}
 

@Override
public void processActionComplex(final ODataRequest request, ODataResponse response, final UriInfo uriInfo,
    final ContentType requestFormat, final ContentType responseFormat)
    throws ODataApplicationException, ODataLibraryException {
  EdmAction action = null;
  Map<String, Parameter> parameters = null;
  Property property = null;
  final List<UriResource> resourcePaths = uriInfo.asUriInfoResource().getUriResourceParts();
  if (resourcePaths.size() > 1) {
    if (resourcePaths.get(0) instanceof UriResourceEntitySet) {
      UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0);
      EdmEntitySet entitySet = uriResourceEntitySet.getEntitySet();
      action = ((UriResourceAction) resourcePaths.get(resourcePaths.size() - 1))
          .getAction();
      parameters = readParameters(action, request.getBody(), requestFormat);
      property =
          dataProvider.processBoundActionComplex(action.getName(), parameters, entitySet, 
              uriResourceEntitySet.getKeyPredicates());
    }
  } else {
    action = ((UriResourceAction) resourcePaths.get(0))
        .getAction();
    parameters = readParameters(action, request.getBody(), requestFormat);
    property = dataProvider.processActionComplex(action.getName(), parameters);
  }
  
  EdmComplexType type = (EdmComplexType) action.getReturnType().getType();
  if (property == null || property.isNull()) {
    if (action.getReturnType().isNullable()) {
      response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
    } else {
      // Not nullable return type so we have to give back an Internal Server Error
      throw new ODataApplicationException("The action could not be executed.",
          HttpStatusCode.INTERNAL_SERVER_ERROR.getStatusCode(), Locale.ROOT);
    }
  } else {
    final Return returnPreference = odata.createPreferences(request.getHeaders(HttpHeader.PREFER)).getReturn();
    if (returnPreference == null || returnPreference == Return.REPRESENTATION) {
      final ContextURL contextURL = ContextURL.with().type(type).build();
      final ComplexSerializerOptions options = ComplexSerializerOptions.with().contextURL(contextURL).build();
      final SerializerResult result =
          odata.createSerializer(responseFormat).complex(serviceMetadata, type, property, options);
      response.setContent(result.getContent());
      response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
      response.setStatusCode(HttpStatusCode.OK.getStatusCode());
    } else {
      response.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
    }
    if (returnPreference != null) {
      response.setHeader(HttpHeader.PREFERENCE_APPLIED,
          PreferencesApplied.with().returnRepresentation(returnPreference).build().toValueString());
    }
  }
}
 

public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo,
    ContentType responseFormat) throws ODataApplicationException, SerializerException {

  // 1st retrieve the requested EntitySet from the uriInfo (representation of the parsed URI)
  List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
  // in our example, the first segment is the EntitySet
  UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0);
  EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

  // 2nd: fetch the data from backend for this requested EntitySetName and deliver as EntitySet
  EntityCollection entityCollection = storage.readEntitySetData(edmEntitySet);

  // 3rd: apply System Query Options
  // modify the result set according to the query options, specified by the end user
  List<Entity> entityList = entityCollection.getEntities();
  EntityCollection returnEntityCollection = new EntityCollection();

  // handle $count: always return the original number of entities, without considering $top and $skip
  CountOption countOption = uriInfo.getCountOption();
  if (countOption != null) {
    boolean isCount = countOption.getValue();
    if (isCount) {
      returnEntityCollection.setCount(entityList.size());
    }
  }
  
  // handle $skip
  SkipOption skipOption = uriInfo.getSkipOption();
  if (skipOption != null) {
    int skipNumber = skipOption.getValue();
    if (skipNumber >= 0) {
      if(skipNumber <= entityList.size()) {
        entityList = entityList.subList(skipNumber, entityList.size());
      } else {
        // The client skipped all entities
        entityList.clear();
      }
    } else {
      throw new ODataApplicationException("Invalid value for $skip", HttpStatusCode.BAD_REQUEST.getStatusCode(),
          Locale.ROOT);
    }
  }
  
  // handle $top
  TopOption topOption = uriInfo.getTopOption();
  if (topOption != null) {
    int topNumber = topOption.getValue();
    if (topNumber >= 0) {
      if(topNumber <= entityList.size()) {
        entityList = entityList.subList(0, topNumber);
      }  // else the client has requested more entities than available => return what we have
    } else {
      throw new ODataApplicationException("Invalid value for $top", HttpStatusCode.BAD_REQUEST.getStatusCode(),
          Locale.ROOT);
    }
  }

  // after applying the system query options, create the EntityCollection based on the reduced list
  for (Entity entity : entityList) {
    returnEntityCollection.getEntities().add(entity);
  }

  // 4th: create a serializer based on the requested format (json)
  ODataSerializer serializer = odata.createSerializer(responseFormat);

  // and serialize the content: transform from the EntitySet object to InputStream
  EdmEntityType edmEntityType = edmEntitySet.getEntityType();
  ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build();

  final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
  EntityCollectionSerializerOptions opts =
      EntityCollectionSerializerOptions.with().contextURL(contextUrl).id(id).count(countOption).build();
  SerializerResult serializerResult =
      serializer.entityCollection(serviceMetadata, edmEntityType, returnEntityCollection, opts);
  InputStream serializedContent = serializerResult.getContent();

  // 5th: configure the response object: set the body, headers and status code
  response.setContent(serializedContent);
  response.setStatusCode(HttpStatusCode.OK.getStatusCode());
  response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

public void readEntityCollection(ODataRequest request, ODataResponse response, UriInfo uriInfo, 
    ContentType responseFormat) throws ODataApplicationException, SerializerException {

	// 1st: retrieve the requested EntitySet from the uriInfo (representation of the parsed URI)
	List<UriResource> resourcePaths = uriInfo.getUriResourceParts();
	// in our example, the first segment is the EntitySet
	UriResourceEntitySet uriResourceEntitySet = (UriResourceEntitySet) resourcePaths.get(0); 
	EdmEntitySet edmEntitySet = uriResourceEntitySet.getEntitySet();

	// 2nd: fetch the data from backend for this requested EntitySetName and deliver as EntitySet
	EntityCollection entityCollection = storage.readEntitySetData(edmEntitySet);
	
	// 3rd: Check if filter system query option is provided and apply the expression if necessary
	FilterOption filterOption = uriInfo.getFilterOption();
	if(filterOption != null) {
		// Apply $filter system query option
		try {
		      List<Entity> entityList = entityCollection.getEntities();
		      Iterator<Entity> entityIterator = entityList.iterator();
		      
		      // Evaluate the expression for each entity
		      // If the expression is evaluated to "true", keep the entity otherwise remove it from the entityList
		      while (entityIterator.hasNext()) {
		    	  // To evaluate the the expression, create an instance of the Filter Expression Visitor and pass
		    	  // the current entity to the constructor
		    	  Entity currentEntity = entityIterator.next();
		    	  Expression filterExpression = filterOption.getExpression();
		    	  FilterExpressionVisitor expressionVisitor = new FilterExpressionVisitor(currentEntity);
		    	  
		    	  // Start evaluating the expression
		    	  Object visitorResult = filterExpression.accept(expressionVisitor);
		    	  
		    	  // The result of the filter expression must be of type Edm.Boolean
		    	  if(visitorResult instanceof Boolean) {
		    		  if(!Boolean.TRUE.equals(visitorResult)) {
		    		    // The expression evaluated to false (or null), so we have to remove the currentEntity from entityList
		    		    entityIterator.remove();
		    		  }
		    	  } else {
		    		  throw new ODataApplicationException("A filter expression must evaulate to type Edm.Boolean", 
		    		      HttpStatusCode.BAD_REQUEST.getStatusCode(), Locale.ENGLISH);
		    	  }
		      }

		    } catch (ExpressionVisitException e) {
		      throw new ODataApplicationException("Exception in filter evaluation",
		          HttpStatusCode.INTERNAL_SERVER_ERROR.getStatusCode(), Locale.ENGLISH);
		    }
	}
	
	// 4th: create a serializer based on the requested format (json)
	ODataSerializer serializer = odata.createSerializer(responseFormat);

	// and serialize the content: transform from the EntitySet object to InputStream
	EdmEntityType edmEntityType = edmEntitySet.getEntityType();
	ContextURL contextUrl = ContextURL.with().entitySet(edmEntitySet).build();

	final String id = request.getRawBaseUri() + "/" + edmEntitySet.getName();
	EntityCollectionSerializerOptions opts = EntityCollectionSerializerOptions.with()
			.contextURL(contextUrl).id(id).build();
	SerializerResult serializerResult = serializer.entityCollection(serviceMetadata, edmEntityType, entityCollection,
			opts);

	InputStream serializedContent = serializerResult.getContent();

	// 5th: configure the response object: set the body, headers and status code
	response.setContent(serializedContent);
	response.setStatusCode(HttpStatusCode.OK.getStatusCode());
	response.setHeader(HttpHeader.CONTENT_TYPE, responseFormat.toContentTypeString());
}
 

@Test
public void batchResponseUmlautsIso() throws Exception {
  List<ODataResponsePart> parts = new ArrayList<ODataResponsePart>();

  ODataResponse response = new ODataResponse();
  response.setStatusCode(HttpStatusCode.OK.getStatusCode());
  response.setHeader(HttpHeader.CONTENT_TYPE,
      ContentType.create(ContentType.TEXT_PLAIN, ContentType.PARAMETER_CHARSET, CS_ISO_8859_1.name())
          .toContentTypeString());
  response.setContent(new ByteArrayInputStream(("Wälter Winter" + CRLF).getBytes(CS_ISO_8859_1)));
  parts.add(new ODataResponsePart(Collections.singletonList(response), false));

  ODataResponse changeSetResponse = new ODataResponse();
  changeSetResponse.setStatusCode(HttpStatusCode.NO_CONTENT.getStatusCode());
  changeSetResponse.setHeader(HttpHeader.CONTENT_ID, "1");
  parts.add(new ODataResponsePart(Collections.singletonList(changeSetResponse), true));

  BatchResponseSerializer serializer = new BatchResponseSerializer();
  final InputStream content = serializer.serialize(parts, BOUNDARY);
  assertNotNull(content);
  final BatchLineReader reader = new BatchLineReader(content);
  final List<String> body = reader.toList();
  reader.close();

  int line = 0;
  assertEquals(24, body.size());
  assertEquals("--" + BOUNDARY + CRLF, body.get(line++));
  assertEquals("Content-Type: application/http" + CRLF, body.get(line++));
  assertEquals("Content-Transfer-Encoding: binary" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("HTTP/1.1 200 OK" + CRLF, body.get(line++));
  assertEquals("Content-Type: text/plain;charset=ISO-8859-1" + CRLF, body.get(line++));
  assertEquals("Content-Length: 15" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("Wälter Winter" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("--" + BOUNDARY + CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("Content-Type: multipart/mixed; boundary=changeset_"));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("Content-Type: application/http" + CRLF, body.get(line++));
  assertEquals("Content-Transfer-Encoding: binary" + CRLF, body.get(line++));
  assertEquals("Content-ID: 1" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals("HTTP/1.1 204 No Content" + CRLF, body.get(line++));
  assertEquals("Content-Length: 0" + CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertEquals(CRLF, body.get(line++));
  assertTrue(body.get(line++).startsWith("--changeset_"));
  assertEquals("--" + BOUNDARY + "--" + CRLF, body.get(line++));
}