001/* 002 * (C) Copyright 2015 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 * Contributors: 017 * Nicolas Chapurlat <nchapurlat@nuxeo.com> 018 */ 019 020package org.nuxeo.ecm.core.io.marshallers.json; 021 022import static javax.ws.rs.core.MediaType.APPLICATION_JSON_TYPE; 023 024import java.io.IOException; 025import java.io.InputStream; 026import java.lang.reflect.Type; 027import java.util.ArrayList; 028import java.util.Iterator; 029import java.util.List; 030 031import org.apache.commons.lang3.reflect.TypeUtils; 032import org.nuxeo.ecm.core.io.registry.MarshallerRegistry; 033import org.nuxeo.ecm.core.io.registry.Reader; 034 035import com.fasterxml.jackson.databind.JsonNode; 036 037/** 038 * Base class to convert json as {@link List}. 039 * <p> 040 * It follow the classic Nuxeo list format : 041 * 042 * <pre> 043 * { 044 * "entity-type": "GIVEN_ENTITY_TYPE", 045 * "entries": [ 046 * {...}, <-- A {@link Reader} must be able to manage this format. 047 * {...}, 048 * ... 049 * {...} 050 * ] 051 * } 052 * </pre> 053 * 054 * <p> 055 * This reader delegates the unmarshalling of entries to the {@link MarshallerRegistry}. A Json {@link Reader} 056 * compatible with the required type and the json format must be registered. 057 * 058 * @param <EntityType> The type of the element of this list. 059 * @since 7.2 060 */ 061public abstract class DefaultListJsonReader<EntityType> extends EntityJsonReader<List<EntityType>> { 062 063 /** 064 * The Java type of the element of this list. 065 */ 066 private final Class<EntityType> elClazz; 067 068 /** 069 * The generic type of the element of this list. 070 */ 071 private final Type elGenericType; 072 073 /** 074 * Use this constructor if the element of the list are not based on Java generic type. 075 * 076 * @param entityType The list "entity-type". 077 * @param elClazz The class of the element of the list. 078 */ 079 public DefaultListJsonReader(String entityType, Class<EntityType> elClazz) { 080 super(entityType); 081 this.elClazz = elClazz; 082 elGenericType = elClazz; 083 } 084 085 /** 086 * Use this constructor if the element of the list are based on Java generic type. 087 * 088 * @param entityType The list "entity-type". 089 * @param elClazz The class of the element of the list. 090 * @param elGenericType The generic type of the list (you can use {@link TypeUtils#parameterize(Class, Type...) to 091 * generate it} 092 */ 093 public DefaultListJsonReader(String entityType, Class<EntityType> elClazz, Type elGenericType) { 094 super(entityType); 095 this.elClazz = elClazz; 096 this.elGenericType = elGenericType; 097 } 098 099 @Override 100 protected List<EntityType> readEntity(JsonNode jn) throws IOException { 101 Reader<EntityType> entryReader = registry.getReader(ctx, elClazz, elGenericType, APPLICATION_JSON_TYPE); 102 List<EntityType> result = new ArrayList<>(); 103 JsonNode entriesNode = jn.get("entries"); 104 if (entriesNode != null && !entriesNode.isNull() && entriesNode.isArray()) { 105 JsonNode entryNode = null; 106 Iterator<JsonNode> it = entriesNode.elements(); 107 while (it.hasNext()) { 108 entryNode = it.next(); 109 try (InputStream in = new InputStreamWithJsonNode(entryNode)) { 110 EntityType doc = entryReader.read(elClazz, elClazz, APPLICATION_JSON_TYPE, in); 111 result.add(doc); 112 } 113 } 114 } 115 return result; 116 } 117 118}