Java tutorial
/* * Copyright 2011 Facebook, 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.facebook.tsdb.tsdash.server; import java.io.IOException; import java.io.PrintWriter; import javax.servlet.ServletException; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.json.simple.JSONArray; import com.facebook.tsdb.tsdash.server.data.TsdbDataProvider; import com.facebook.tsdb.tsdash.server.data.TsdbDataProviderFactory; public class MetricsEndpoint extends TsdbServlet { private static final long serialVersionUID = 1L; @Override @SuppressWarnings("unchecked") public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { PrintWriter out = response.getWriter(); try { TsdbDataProvider dataProvider = TsdbDataProviderFactory.get(); String[] metrics = dataProvider.getMetrics(); response.setContentType("text/plain"); JSONArray encoded = new JSONArray(); for (String metric : metrics) { encoded.add(metric); } out.println(encoded.toJSONString()); } catch (Exception e) { out.println(getErrorResponse(e)); } out.close(); } }