Java tutorial
/** * Copyright 2011 The Apache Software Foundation * * 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 com.alibaba.wasp.master; import com.alibaba.wasp.ServerLoad; import com.alibaba.wasp.ServerName; import com.alibaba.wasp.monitoring.StateDumpServlet; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.monitoring.LogMonitoring; import org.apache.hadoop.hbase.monitoring.TaskMonitor; import org.apache.hadoop.util.ReflectionUtils; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.io.OutputStream; import java.io.PrintWriter; import java.util.Date; import java.util.Map; public class FMasterDumpServlet extends StateDumpServlet { private static final long serialVersionUID = 1L; private static final String LINE = "==========================================================="; @Override public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException { FMaster master = (FMaster) getServletContext().getAttribute(FMaster.MASTER); assert master != null : "No Master in context!"; response.setContentType("text/plain"); OutputStream os = response.getOutputStream(); PrintWriter out = new PrintWriter(os); out.println("Master status for " + master.getServerName() + " as of " + new Date()); out.println("\n\nVersion Info:"); out.println(LINE); dumpVersionInfo(out); out.println("\n\nTasks:"); out.println(LINE); TaskMonitor.get().dumpAsText(out); out.println("\n\nServers:"); out.println(LINE); dumpServers(master, out); out.println("\n\nEntityGroups-in-transition:"); out.println(LINE); dumpRIT(master, out); out.println("\n\nExecutors:"); out.println(LINE); dumpExecutors(master.getExecutorService(), out); out.println("\n\nStacks:"); out.println(LINE); ReflectionUtils.printThreadInfo(out, ""); out.println("\n\nMaster configuration:"); out.println(LINE); Configuration conf = master.getConfiguration(); out.flush(); conf.writeXml(os); os.flush(); // out.println("\n\nRecent fserver aborts:"); // out.println(LINE); // master.getFServerFatalLogBuffer().dumpTo(out); out.println("\n\nLogs"); out.println(LINE); long tailKb = getTailKbParam(request); LogMonitoring.dumpTailOfLogs(out, tailKb); out.flush(); } private void dumpRIT(FMaster master, PrintWriter out) { Map<String, EntityGroupState> entityGroupsInTransition = master.getAssignmentManager() .getEntityGroupStates().getEntityGroupsInTransition(); for (Map.Entry<String, EntityGroupState> e : entityGroupsInTransition.entrySet()) { String rid = e.getKey(); EntityGroupState entityGroupState = e.getValue(); out.println("EntityGroup " + rid + ": " + entityGroupState.toDescriptiveString()); } } private void dumpServers(FMaster master, PrintWriter out) { Map<ServerName, ServerLoad> servers = master.getFServerManager().getOnlineServers(); for (Map.Entry<ServerName, ServerLoad> e : servers.entrySet()) { out.println(e.getKey() + ": " + e.getValue()); } } }