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/* * Copyright (C) 2008 Google Inc. * * 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 com.google.gson; import com.google.gson.internal.LinkedTreeMap; import java.util.Map; import java.util.Set; /** * A class representing an object type in Json. An object consists of name-value pairs where names * are strings, and values are any other type of {@link JsonElement}. This allows for a creating a * tree of JsonElements. The member elements of this object are maintained in order they were added. * * @author Inderjeet Singh * @author Joel Leitch */ public final class JsonObject extends JsonElement { private final LinkedTreeMap<String, JsonElement> members = new LinkedTreeMap<String, JsonElement>(); /** * Creates a deep copy of this element and all its children * @since 2.8.2 */ @Override public JsonObject deepCopy() { JsonObject result = new JsonObject(); for (Map.Entry<String, JsonElement> entry : members.entrySet()) { result.add(entry.getKey(), entry.getValue().deepCopy()); } return result; } /** * Adds a member, which is a name-value pair, to self. The name must be a String, but the value * can be an arbitrary JsonElement, thereby allowing you to build a full tree of JsonElements * rooted at this node. * * @param property name of the member. * @param value the member object. */ public void add(String property, JsonElement value) { members.put(property, value == null ? JsonNull.INSTANCE : value); } /** * Removes the {@code property} from this {@link JsonObject}. * * @param property name of the member that should be removed. * @return the {@link JsonElement} object that is being removed. * @since 1.3 */ public JsonElement remove(String property) { return members.remove(property); } /** * Convenience method to add a primitive member. The specified value is converted to a * JsonPrimitive of String. * * @param property name of the member. * @param value the string value associated with the member. */ public void addProperty(String property, String value) { add(property, value == null ? JsonNull.INSTANCE : new JsonPrimitive(value)); } /** * Convenience method to add a primitive member. The specified value is converted to a * JsonPrimitive of Number. * * @param property name of the member. * @param value the number value associated with the member. */ public void addProperty(String property, Number value) { add(property, value == null ? JsonNull.INSTANCE : new JsonPrimitive(value)); } /** * Convenience method to add a boolean member. The specified value is converted to a * JsonPrimitive of Boolean. * * @param property name of the member. * @param value the number value associated with the member. */ public void addProperty(String property, Boolean value) { add(property, value == null ? JsonNull.INSTANCE : new JsonPrimitive(value)); } /** * Convenience method to add a char member. The specified value is converted to a * JsonPrimitive of Character. * * @param property name of the member. * @param value the number value associated with the member. */ public void addProperty(String property, Character value) { add(property, value == null ? JsonNull.INSTANCE : new JsonPrimitive(value)); } /** * Returns a set of members of this object. The set is ordered, and the order is in which the * elements were added. * * @return a set of members of this object. */ public Set<Map.Entry<String, JsonElement>> entrySet() { return members.entrySet(); } /** * Returns a set of members key values. * * @return a set of member keys as Strings * @since 2.8.1 */ public Set<String> keySet() { return members.keySet(); } /** * Returns the number of key/value pairs in the object. * * @return the number of key/value pairs in the object. */ public int size() { return members.size(); } /** * Convenience method to check if a member with the specified name is present in this object. * * @param memberName name of the member that is being checked for presence. * @return true if there is a member with the specified name, false otherwise. */ public boolean has(String memberName) { return members.containsKey(memberName); } /** * Returns the member with the specified name. * * @param memberName name of the member that is being requested. * @return the member matching the name. Null if no such member exists. */ public JsonElement get(String memberName) { return members.get(memberName); } /** * Convenience method to get the specified member as a JsonPrimitive element. * * @param memberName name of the member being requested. * @return the JsonPrimitive corresponding to the specified member. */ public JsonPrimitive getAsJsonPrimitive(String memberName) { return (JsonPrimitive) members.get(memberName); } /** * Convenience method to get the specified member as a JsonArray. * * @param memberName name of the member being requested. * @return the JsonArray corresponding to the specified member. */ public JsonArray getAsJsonArray(String memberName) { return (JsonArray) members.get(memberName); } /** * Convenience method to get the specified member as a JsonObject. * * @param memberName name of the member being requested. * @return the JsonObject corresponding to the specified member. */ public JsonObject getAsJsonObject(String memberName) { return (JsonObject) members.get(memberName); } @Override public boolean equals(Object o) { return (o == this) || (o instanceof JsonObject && ((JsonObject) o).members.equals(members)); } @Override public int hashCode() { return members.hashCode(); } }