Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package org.apache.olingo.client.core.data; import java.io.IOException; import java.io.InputStream; import java.net.URI; import java.util.Iterator; import org.apache.commons.lang3.StringUtils; import org.apache.olingo.client.api.data.ResWrap; import org.apache.olingo.client.api.data.ServiceDocument; import org.apache.olingo.client.api.serialization.ODataDeserializerException; import org.apache.olingo.client.core.serialization.JsonDeserializer; import org.apache.olingo.commons.api.Constants; import com.fasterxml.jackson.core.JsonFactory; import com.fasterxml.jackson.core.JsonParser; import com.fasterxml.jackson.databind.JsonNode; import com.fasterxml.jackson.databind.ObjectMapper; import com.fasterxml.jackson.databind.node.ObjectNode; public class JSONServiceDocumentDeserializer extends JsonDeserializer { public JSONServiceDocumentDeserializer(final boolean serverMode) { super(serverMode); } protected ResWrap<ServiceDocument> doDeserialize(final JsonParser parser) throws IOException { final ObjectNode tree = parser.getCodec().readTree(parser); ServiceDocumentImpl serviceDocument = new ServiceDocumentImpl(); final String metadataETag; if (tree.hasNonNull(Constants.JSON_METADATA_ETAG)) { metadataETag = tree.get(Constants.JSON_METADATA_ETAG).textValue(); tree.remove(Constants.JSON_METADATA_ETAG); } else { metadataETag = null; } final URI contextURL; if (tree.hasNonNull(Constants.JSON_CONTEXT)) { contextURL = URI.create(tree.get(Constants.JSON_CONTEXT).textValue()); tree.remove(Constants.JSON_CONTEXT); } else if (tree.hasNonNull(Constants.JSON_METADATA)) { contextURL = URI.create(tree.get(Constants.JSON_METADATA).textValue()); tree.remove(Constants.JSON_METADATA); } else { contextURL = null; } serviceDocument.setMetadata(contextURL == null ? null : contextURL.toASCIIString()); for (final Iterator<JsonNode> itor = tree.get(Constants.VALUE).elements(); itor.hasNext();) { final JsonNode node = itor.next(); final ServiceDocumentItemImpl item = new ServiceDocumentItemImpl(); item.setName(node.get("name").asText()); JsonNode titleNode = node.get("title"); if (titleNode != null) { item.setTitle(titleNode.asText()); } item.setUrl(node.get("url").asText()); final String kind = node.has("kind") ? node.get("kind").asText() : null; if (StringUtils.isBlank(kind) || "EntitySet".equals(kind)) { serviceDocument.getEntitySets().add(item); } else if ("Singleton".equals(kind)) { serviceDocument.getSingletons().add(item); } else if ("FunctionImport".equals(kind)) { serviceDocument.getFunctionImports().add(item); } else if ("ServiceDocument".equals(kind)) { serviceDocument.getRelatedServiceDocuments().add(item); } } return new ResWrap<ServiceDocument>(contextURL, metadataETag, serviceDocument); } public ResWrap<ServiceDocument> toServiceDocument(final InputStream input) throws ODataDeserializerException { try { JsonParser parser = new JsonFactory(new ObjectMapper()).createParser(input); return doDeserialize(parser); } catch (final IOException e) { throw new ODataDeserializerException(e); } } }