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/* * Copyright 2012-2019 the original author or authors. * * 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 * * https://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.springframework.boot.configurationprocessor.metadata; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.OutputStream; import java.nio.charset.StandardCharsets; import java.util.ArrayList; import java.util.HashMap; import java.util.Iterator; import java.util.List; import java.util.Map; import org.springframework.boot.configurationprocessor.json.JSONArray; import org.springframework.boot.configurationprocessor.json.JSONObject; import org.springframework.boot.configurationprocessor.metadata.ItemMetadata.ItemType; /** * Marshaller to write {@link ConfigurationMetadata} as JSON. * * @author Stephane Nicoll * @author Phillip Webb * @since 1.2.0 */ public class JsonMarshaller { private static final int BUFFER_SIZE = 4098; public void write(ConfigurationMetadata metadata, OutputStream outputStream) throws IOException { try { JSONObject object = new JSONObject(); JsonConverter converter = new JsonConverter(); object.put("groups", converter.toJsonArray(metadata, ItemType.GROUP)); object.put("properties", converter.toJsonArray(metadata, ItemType.PROPERTY)); object.put("hints", converter.toJsonArray(metadata.getHints())); outputStream.write(object.toString(2).getBytes(StandardCharsets.UTF_8)); } catch (Exception ex) { if (ex instanceof IOException) { throw (IOException) ex; } if (ex instanceof RuntimeException) { throw (RuntimeException) ex; } throw new IllegalStateException(ex); } } public ConfigurationMetadata read(InputStream inputStream) throws Exception { ConfigurationMetadata metadata = new ConfigurationMetadata(); JSONObject object = new JSONObject(toString(inputStream)); JSONArray groups = object.optJSONArray("groups"); if (groups != null) { for (int i = 0; i < groups.length(); i++) { metadata.add(toItemMetadata((JSONObject) groups.get(i), ItemType.GROUP)); } } JSONArray properties = object.optJSONArray("properties"); if (properties != null) { for (int i = 0; i < properties.length(); i++) { metadata.add(toItemMetadata((JSONObject) properties.get(i), ItemType.PROPERTY)); } } JSONArray hints = object.optJSONArray("hints"); if (hints != null) { for (int i = 0; i < hints.length(); i++) { metadata.add(toItemHint((JSONObject) hints.get(i))); } } return metadata; } private ItemMetadata toItemMetadata(JSONObject object, ItemType itemType) throws Exception { String name = object.getString("name"); String type = object.optString("type", null); String description = object.optString("description", null); String sourceType = object.optString("sourceType", null); String sourceMethod = object.optString("sourceMethod", null); Object defaultValue = readItemValue(object.opt("defaultValue")); ItemDeprecation deprecation = toItemDeprecation(object); return new ItemMetadata(itemType, name, null, type, sourceType, sourceMethod, description, defaultValue, deprecation); } private ItemDeprecation toItemDeprecation(JSONObject object) throws Exception { if (object.has("deprecation")) { JSONObject deprecationJsonObject = object.getJSONObject("deprecation"); ItemDeprecation deprecation = new ItemDeprecation(); deprecation.setLevel(deprecationJsonObject.optString("level", null)); deprecation.setReason(deprecationJsonObject.optString("reason", null)); deprecation.setReplacement(deprecationJsonObject.optString("replacement", null)); return deprecation; } return object.optBoolean("deprecated") ? new ItemDeprecation() : null; } private ItemHint toItemHint(JSONObject object) throws Exception { String name = object.getString("name"); List<ItemHint.ValueHint> values = new ArrayList<>(); if (object.has("values")) { JSONArray valuesArray = object.getJSONArray("values"); for (int i = 0; i < valuesArray.length(); i++) { values.add(toValueHint((JSONObject) valuesArray.get(i))); } } List<ItemHint.ValueProvider> providers = new ArrayList<>(); if (object.has("providers")) { JSONArray providersObject = object.getJSONArray("providers"); for (int i = 0; i < providersObject.length(); i++) { providers.add(toValueProvider((JSONObject) providersObject.get(i))); } } return new ItemHint(name, values, providers); } private ItemHint.ValueHint toValueHint(JSONObject object) throws Exception { Object value = readItemValue(object.get("value")); String description = object.optString("description", null); return new ItemHint.ValueHint(value, description); } private ItemHint.ValueProvider toValueProvider(JSONObject object) throws Exception { String name = object.getString("name"); Map<String, Object> parameters = new HashMap<>(); if (object.has("parameters")) { JSONObject parametersObject = object.getJSONObject("parameters"); for (Iterator<?> iterator = parametersObject.keys(); iterator.hasNext();) { String key = (String) iterator.next(); Object value = readItemValue(parametersObject.get(key)); parameters.put(key, value); } } return new ItemHint.ValueProvider(name, parameters); } private Object readItemValue(Object value) throws Exception { if (value instanceof JSONArray) { JSONArray array = (JSONArray) value; Object[] content = new Object[array.length()]; for (int i = 0; i < array.length(); i++) { content[i] = array.get(i); } return content; } return value; } private String toString(InputStream inputStream) throws IOException { StringBuilder out = new StringBuilder(); InputStreamReader reader = new InputStreamReader(inputStream, StandardCharsets.UTF_8); char[] buffer = new char[BUFFER_SIZE]; int bytesRead; while ((bytesRead = reader.read(buffer)) != -1) { out.append(buffer, 0, bytesRead); } return out.toString(); } }