Java tutorial
/* * #%L * wcm.io * %% * Copyright (C) 2015 wcm.io * %% * 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. * #L% */ package io.wcm.dam.assetservice.impl; import io.wcm.wcm.commons.contenttype.ContentType; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.http.HttpServletResponse; import org.apache.commons.lang3.CharEncoding; import org.apache.sling.api.SlingHttpServletRequest; import org.apache.sling.api.SlingHttpServletResponse; import org.apache.sling.api.servlets.SlingSafeMethodsServlet; import org.apache.sling.commons.json.JSONException; import org.apache.sling.commons.json.JSONObject; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Returns generated data version if called on the root of an allowed asset path in DAM. */ class DataVersionServlet extends SlingSafeMethodsServlet { private static final long serialVersionUID = 1L; private final DamPathHandler damPathHandler; private static final Logger log = LoggerFactory.getLogger(DataVersionServlet.class); public DataVersionServlet(DamPathHandler damPathHandler) { this.damPathHandler = damPathHandler; } @Override protected void doGet(SlingHttpServletRequest request, SlingHttpServletResponse response) throws ServletException, IOException { String path = request.getResource().getPath(); // check path is a valid DAM root folder path for asset service if (!damPathHandler.isAllowedDataVersionPath(path)) { log.debug("Path not allowed to get data version {}", path); response.sendError(HttpServletResponse.SC_NOT_FOUND); return; } // return data version as JSON try { JSONObject jsonResponse = new JSONObject(); jsonResponse.put("dataVersion", damPathHandler.getDataVersion()); response.setContentType(ContentType.JSON); response.setCharacterEncoding(CharEncoding.UTF_8); response.getWriter().write(jsonResponse.toString()); } catch (JSONException ex) { throw new ServletException("Unable to generate JSON.", ex); } } }