| /* |
| * 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.slider.providers.agent.application.metadata; |
| |
| import com.google.gson.Gson; |
| import com.google.gson.GsonBuilder; |
| |
| import org.apache.commons.digester.Digester; |
| import org.apache.commons.io.IOUtils; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| import org.xml.sax.SAXException; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.StringWriter; |
| |
| /** |
| * This abstract class provide common functionality to parse metainfo.json for |
| * either master package or add on packages. |
| */ |
| public abstract class AbstractMetainfoParser { |
| protected final GsonBuilder gsonBuilder = new GsonBuilder(); |
| protected final Gson gson; |
| private static final Logger log = LoggerFactory |
| .getLogger(AbstractMetainfoParser.class); |
| |
| public AbstractMetainfoParser() { |
| gson = gsonBuilder.create(); |
| } |
| |
| /** |
| * Convert to a JSON string |
| * |
| * @return a JSON string description |
| * |
| * @throws IOException Problems mapping/writing the object |
| */ |
| public String toJsonString(Metainfo metaInfo) throws IOException { |
| return gson.toJson(metaInfo); |
| } |
| |
| /** |
| * Convert from JSON |
| * |
| * @param json input |
| * |
| * @return the parsed JSON |
| * |
| * @throws IOException IO |
| */ |
| public Metainfo fromJsonString(String json) |
| throws IOException { |
| return gson.fromJson(json, Metainfo.class); |
| } |
| |
| /** |
| * Parse metainfo from an IOStream |
| * |
| * @param is |
| * |
| * @return |
| * |
| * @throws IOException |
| */ |
| public Metainfo fromJsonStream(InputStream is) throws IOException { |
| log.debug("loading from xml stream"); |
| StringWriter writer = new StringWriter(); |
| IOUtils.copy(is, writer); |
| return fromJsonString(writer.toString()); |
| } |
| |
| /** |
| * Parse metainfo from an XML formatted IOStream |
| * |
| * @param metainfoStream |
| * |
| * @return |
| * |
| * @throws IOException |
| */ |
| public Metainfo fromXmlStream(InputStream metainfoStream) throws IOException { |
| log.debug("loading from xml stream"); |
| Digester digester = new Digester(); |
| digester.setValidating(false); |
| |
| composeSchema(digester); |
| |
| try { |
| return (Metainfo) digester.parse(metainfoStream); |
| } catch (IOException e) { |
| log.debug("IOException in metainfoparser during fromXmlStream: " |
| + e.getMessage()); |
| } catch (SAXException e) { |
| log.debug("SAXException in metainfoparser during fromXmlStream: " |
| + e.getMessage()); |
| } finally { |
| metainfoStream.close(); |
| } |
| |
| return null; |
| } |
| |
| /** |
| * Compose the schema for the metainfo |
| * |
| * @param Digester - The Digester object we passed in to compose the schema |
| * |
| * @return |
| * |
| * @throws IOException |
| */ |
| abstract protected void composeSchema(Digester digester); |
| } |