Java tutorial
/* * Copyright 2015 Collective, 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.collective.celos.servlet; import com.collective.celos.*; import com.fasterxml.jackson.databind.node.ArrayNode; import com.fasterxml.jackson.databind.node.ObjectNode; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.util.SortedSet; import java.util.TreeSet; /** * Returns list of IDs of configured workflows as JSON. * * GET /workflow-list * == * { * "ids": [ "workflow-1", "workflow-2" ] * } */ @SuppressWarnings("serial") public class JSONWorkflowListServlet extends AbstractJSONServlet { protected void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException { try { Scheduler sch = getOrCreateCachedScheduler(); WorkflowConfiguration cfg = sch.getWorkflowConfiguration(); ObjectNode object = createJSONObject(cfg); writer.writeValue(res.getOutputStream(), object); } catch (Exception e) { throw new ServletException(e); } } ObjectNode createJSONObject(WorkflowConfiguration cfg) { // Make sure the IDs are sorted SortedSet<String> ids = new TreeSet<String>(); for (Workflow wf : cfg.getWorkflows()) { ids.add(wf.getID().toString()); } ArrayNode list = Util.MAPPER.createArrayNode(); for (String id : ids) { list.add(id); } ObjectNode object = Util.MAPPER.createObjectNode(); object.put(CelosClient.IDS_PARAM, list); return object; } }