| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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.android.statementservice.retriever; |
| |
| import android.util.JsonReader; |
| import android.util.JsonToken; |
| |
| import org.json.JSONArray; |
| import org.json.JSONException; |
| import org.json.JSONObject; |
| |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * A helper class that creates a {@link JSONObject} from a {@link JsonReader}. |
| */ |
| public final class JsonParser { |
| |
| private JsonParser() {} |
| |
| /** |
| * Consumes and parses exactly one JSON object from the {@link JsonReader}. |
| * The object's fields can only be objects, strings or arrays of strings. |
| */ |
| public static JSONObject parse(JsonReader reader) throws IOException, JSONException { |
| JSONObject output = new JSONObject(); |
| String errorMsg = null; |
| |
| reader.beginObject(); |
| while (reader.hasNext()) { |
| String fieldName = reader.nextName(); |
| |
| if (output.has(fieldName)) { |
| errorMsg = "Duplicate field name."; |
| reader.skipValue(); |
| continue; |
| } |
| |
| JsonToken token = reader.peek(); |
| if (token.equals(JsonToken.BEGIN_ARRAY)) { |
| output.put(fieldName, new JSONArray(parseArray(reader))); |
| } else if (token.equals(JsonToken.STRING)) { |
| output.put(fieldName, reader.nextString()); |
| } else if (token.equals(JsonToken.BEGIN_OBJECT)) { |
| try { |
| output.put(fieldName, parse(reader)); |
| } catch (JSONException e) { |
| errorMsg = e.getMessage(); |
| } |
| } else { |
| reader.skipValue(); |
| errorMsg = "Unsupported value type."; |
| } |
| } |
| reader.endObject(); |
| |
| if (errorMsg != null) { |
| throw new JSONException(errorMsg); |
| } |
| |
| return output; |
| } |
| |
| /** |
| * Parses one string array from the {@link JsonReader}. |
| */ |
| public static List<String> parseArray(JsonReader reader) throws IOException { |
| ArrayList<String> output = new ArrayList<>(); |
| |
| reader.beginArray(); |
| while (reader.hasNext()) { |
| output.add(reader.nextString()); |
| } |
| reader.endArray(); |
| |
| return output; |
| } |
| } |