Java tutorial
/* * Copyright Red Hat, Inc. and/or its affiliates * and other contributors as indicated by the @author tags and * the COPYRIGHT.txt file distributed with this work. * * Licensed 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.teiid.olingo; import java.io.IOException; import java.net.URI; import java.util.List; import org.apache.commons.codec.DecoderException; import org.apache.olingo.commons.api.Constants; import org.apache.olingo.commons.api.data.ComplexValue; import org.apache.olingo.commons.api.data.ContextURL; import org.apache.olingo.commons.api.data.Property; import org.apache.olingo.commons.api.edm.EdmComplexType; import org.apache.olingo.commons.api.format.ContentType; import org.apache.olingo.server.api.ServiceMetadata; import org.apache.olingo.server.api.serializer.SerializerException; import org.apache.olingo.server.api.serializer.SerializerResult; import org.apache.olingo.server.core.serializer.SerializerResultImpl; import org.apache.olingo.server.core.serializer.json.ODataJsonSerializer; import org.apache.olingo.server.core.serializer.utils.CircleStreamBuffer; import org.apache.olingo.server.core.serializer.utils.ContentTypeHelper; import org.apache.olingo.server.core.serializer.utils.ContextURLBuilder; import com.fasterxml.jackson.core.JsonFactory; import com.fasterxml.jackson.core.JsonGenerator; public class TeiidODataJsonSerializer extends ODataJsonSerializer { private boolean isODataMetadataFull; private boolean isODataMetadataNone; public TeiidODataJsonSerializer(ContentType contentType) { super(contentType); isODataMetadataNone = ContentTypeHelper.isODataMetadataNone(contentType); isODataMetadataFull = ContentTypeHelper.isODataMetadataFull(contentType); } public SerializerResult complexCollection(final ServiceMetadata metadata, final List<List<ComplexReturnType>> result, final ContextURL contextURL, final URI nextLink) throws SerializerException { CircleStreamBuffer buffer = new CircleStreamBuffer(); try { JsonGenerator json = new JsonFactory().createGenerator(buffer.getOutputStream()); json.writeStartObject(); if (contextURL != null && (isODataMetadataFull || !isODataMetadataNone)) { json.writeStringField(Constants.JSON_CONTEXT, ContextURLBuilder.create(contextURL).toASCIIString()); } json.writeFieldName(Constants.VALUE); json.writeStartArray(); for (List<ComplexReturnType> ct : result) { json.writeStartObject(); for (final ComplexReturnType type : ct) { if (!type.isExpand()) { json.writeStringField(type.getName() + Constants.JSON_NAVIGATION_LINK, type.getEntity().getId().toASCIIString()); } else { json.writeFieldName(type.getName()); writeEntity(metadata, type.getEdmEntityType(), type.getEntity(), null, null, null, null, false, null, type.getName(), json); } } json.writeEndObject(); } json.writeEndArray(); if (nextLink != null) { json.writeStringField(Constants.JSON_NEXT_LINK, nextLink.toASCIIString()); } json.close(); } catch (final IOException | DecoderException e) { throw new SerializerException("An I/O exception occurred.", e, SerializerException.MessageKeys.IO_EXCEPTION); } return SerializerResultImpl.with().content(buffer.getInputStream()).build(); } public SerializerResult complexCollection(final ServiceMetadata metadata, final EdmComplexType type, final Property result, final ContextURL contextURL, final URI nextLink) throws SerializerException { CircleStreamBuffer buffer = new CircleStreamBuffer(); try { JsonGenerator json = new JsonFactory().createGenerator(buffer.getOutputStream()); json.writeStartObject(); if (contextURL != null && (isODataMetadataFull || !isODataMetadataNone)) { json.writeStringField(Constants.JSON_CONTEXT, ContextURLBuilder.create(contextURL).toASCIIString()); } json.writeFieldName(Constants.VALUE); json.writeStartArray(); for (Object value : result.asCollection()) { json.writeStartObject(); writeComplexValue(metadata, type, ((ComplexValue) value).getValue(), null, json, null, (ComplexValue) value, null, result.getName()); json.writeEndObject(); } json.writeEndArray(); if (nextLink != null) { json.writeStringField(Constants.JSON_NEXT_LINK, nextLink.toASCIIString()); } json.close(); } catch (final IOException e) { throw new SerializerException("An I/O exception occurred.", e, SerializerException.MessageKeys.IO_EXCEPTION); } return SerializerResultImpl.with().content(buffer.getInputStream()).build(); } }