| /* |
| * 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.johnzon.core; |
| |
| import java.util.Map; |
| |
| import javax.json.JsonMergePatch; |
| import javax.json.JsonObject; |
| import javax.json.JsonObjectBuilder; |
| import javax.json.JsonValue; |
| |
| import static java.util.Collections.emptyMap; |
| |
| /** |
| * Creates a JsonMergePatch as diff between two JsonValues |
| */ |
| class JsonMergePatchDiff extends DiffBase { |
| private final BufferStrategy.BufferProvider<char[]> bufferProvider; |
| private final JsonValue source; |
| private final JsonValue target; |
| |
| public JsonMergePatchDiff(final JsonValue source, final JsonValue target, |
| final BufferStrategy.BufferProvider<char[]> bufferProvider) { |
| this.bufferProvider = bufferProvider; |
| this.source = source; |
| this.target = target; |
| } |
| |
| public JsonMergePatch calculateDiff() { |
| return new JsonMergePatchImpl(diff(source, target), bufferProvider); |
| } |
| |
| private JsonValue diff(JsonValue source, JsonValue target) { |
| JsonObjectBuilder builder = new JsonObjectBuilderImpl(emptyMap(), bufferProvider, RejectDuplicateKeysMode.DEFAULT); |
| |
| if (isJsonObject(source) && isJsonObject(target)) { |
| JsonObject srcObj = source.asJsonObject(); |
| JsonObject targetObj = target.asJsonObject(); |
| for (Map.Entry<String, JsonValue> sourceEntry : srcObj.entrySet()) { |
| String attributeName = sourceEntry.getKey(); |
| if (targetObj.containsKey(attributeName)) { |
| // compare the attribute values |
| JsonValue attribDiff = diff(sourceEntry.getValue(), targetObj.get(attributeName)); |
| if (!JsonValue.EMPTY_JSON_OBJECT.equals(attribDiff)) { |
| builder.add(attributeName, attribDiff); |
| } |
| } else { |
| // attribute got removed |
| builder.add(attributeName, JsonValue.NULL); |
| } |
| } |
| |
| for (Map.Entry<String, JsonValue> targetEntry : targetObj.entrySet()) { |
| String attributeName = targetEntry.getKey(); |
| if (!srcObj.containsKey(attributeName)) { |
| // add operation |
| builder.add(attributeName, targetEntry.getValue()); |
| } |
| } |
| |
| return builder.build(); |
| } else if (source.equals(target)) { |
| // if the two objects are identical, then return an empty patch |
| return JsonValue.EMPTY_JSON_OBJECT; |
| } else { |
| // as defined in the RFC anything else than comparing JsonObjects will result |
| // in completely replacing the source with the target |
| // That means our target is the patch. |
| return target; |
| } |
| } |
| } |