| /** |
| * 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 |
| * <p/> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p/> |
| * 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.atlas.catalog; |
| |
| import com.google.gson.stream.JsonWriter; |
| import org.apache.atlas.catalog.exception.CatalogRuntimeException; |
| |
| import javax.ws.rs.core.UriInfo; |
| import java.io.IOException; |
| import java.io.StringWriter; |
| import java.io.Writer; |
| import java.util.Collection; |
| import java.util.LinkedHashMap; |
| import java.util.Map; |
| |
| /** |
| * JSON serializer. |
| */ |
| public class JsonSerializer { |
| public String serialize(Result result, UriInfo ui) { |
| Writer json = new StringWriter(); |
| JsonWriter writer = new JsonWriter(json); |
| writer.setIndent(" "); |
| |
| try { |
| writeValue(writer, result.getPropertyMaps(), ui.getBaseUri().toASCIIString()); |
| } catch (IOException e) { |
| throw new CatalogRuntimeException("Unable to write JSON response.", e); |
| } |
| return json.toString(); |
| } |
| |
| private void writeValue(JsonWriter writer, Object value, String baseUrl) throws IOException { |
| if (value == null) { |
| writer.nullValue(); |
| } else if (value instanceof Map) { |
| writer.beginObject(); |
| LinkedHashMap<String, Object> nonScalarMap = new LinkedHashMap<>(); |
| for (Map.Entry<String, Object> entry : ((Map<String, Object>) value).entrySet()) { |
| String key = entry.getKey(); |
| Object val = entry.getValue(); |
| |
| if (val == null || ! (val instanceof Collection || val instanceof Map)) { |
| //todo: use a token in value instead of prop name |
| if (key.equals("href")) { |
| val = baseUrl + String.valueOf(val); |
| } |
| writer.name(key); |
| writeValue(writer, val, baseUrl); |
| } else { |
| nonScalarMap.put(key, val); |
| } |
| } |
| for (Map.Entry<String, Object> entry : nonScalarMap.entrySet()) { |
| writer.name(entry.getKey()); |
| writeValue(writer, entry.getValue(), baseUrl); |
| } |
| writer.endObject(); |
| } else if (value instanceof Collection) { |
| writer.beginArray(); |
| for (Object o : (Collection) value) { |
| writeValue(writer, o, baseUrl); |
| } |
| writer.endArray(); |
| } else if (value instanceof Number) { |
| writer.value((Number) value); |
| } else if (value instanceof Boolean) { |
| writer.value((Boolean) value); |
| } else { |
| // everything else is String |
| writer.value(String.valueOf(value)); |
| } |
| } |
| } |