J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 2003-2004 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | |
| 26 | package com.sun.jmx.remote.internal; |
| 27 | |
| 28 | import java.io.IOException; |
| 29 | |
| 30 | import com.sun.jmx.remote.util.ClassLogger; |
| 31 | |
| 32 | public abstract class ServerCommunicatorAdmin { |
| 33 | public ServerCommunicatorAdmin(long timeout) { |
| 34 | if (logger.traceOn()) { |
| 35 | logger.trace("Constructor", |
| 36 | "Creates a new ServerCommunicatorAdmin object "+ |
| 37 | "with the timeout "+timeout); |
| 38 | } |
| 39 | |
| 40 | this.timeout = timeout; |
| 41 | |
| 42 | timestamp = 0; |
| 43 | if (timeout < Long.MAX_VALUE) { |
| 44 | Runnable timeoutTask = new Timeout(); |
| 45 | final Thread t = new Thread(timeoutTask); |
| 46 | t.setName("JMX server connection timeout " + t.getId()); |
| 47 | // If you change this name you will need to change a unit test |
| 48 | // (NoServerTimeoutTest) |
| 49 | t.setDaemon(true); |
| 50 | t.start(); |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | /** |
| 55 | * Tells that a new request message is received. |
| 56 | * A caller of this method should always call the method |
| 57 | * <code>rspOutgoing</code> to inform that a response is sent out |
| 58 | * for the received request. |
| 59 | * @return the value of the termination flag: |
| 60 | * <ul><code>true</code> if the connection is already being terminated, |
| 61 | * <br><code>false</code> otherwise.</ul> |
| 62 | */ |
| 63 | public boolean reqIncoming() { |
| 64 | if (logger.traceOn()) { |
| 65 | logger.trace("reqIncoming", "Receive a new request."); |
| 66 | } |
| 67 | |
| 68 | synchronized(lock) { |
| 69 | if (terminated) { |
| 70 | logger.warning("reqIncoming", |
| 71 | "The server has decided to close " + |
| 72 | "this client connection."); |
| 73 | } |
| 74 | ++currentJobs; |
| 75 | |
| 76 | return terminated; |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * Tells that a response is sent out for a received request. |
| 82 | * @return the value of the termination flag: |
| 83 | * <ul><code>true</code> if the connection is already being terminated, |
| 84 | * <br><code>false</code> otherwise.</ul> |
| 85 | */ |
| 86 | public boolean rspOutgoing() { |
| 87 | if (logger.traceOn()) { |
| 88 | logger.trace("reqIncoming", "Finish a request."); |
| 89 | } |
| 90 | |
| 91 | synchronized(lock) { |
| 92 | if (--currentJobs == 0) { |
| 93 | timestamp = System.currentTimeMillis(); |
| 94 | logtime("Admin: Timestamp=",timestamp); |
| 95 | // tells the adminor to restart waiting with timeout |
| 96 | lock.notify(); |
| 97 | } |
| 98 | return terminated; |
| 99 | } |
| 100 | } |
| 101 | |
| 102 | /** |
| 103 | * Called by this class to tell an implementation to do stop. |
| 104 | */ |
| 105 | protected abstract void doStop(); |
| 106 | |
| 107 | /** |
| 108 | * Terminates this object. |
| 109 | * Called only by outside, so do not need to call doStop |
| 110 | */ |
| 111 | public void terminate() { |
| 112 | if (logger.traceOn()) { |
| 113 | logger.trace("terminate", |
| 114 | "terminate the ServerCommunicatorAdmin object."); |
| 115 | } |
| 116 | |
| 117 | synchronized(lock) { |
| 118 | if (terminated) { |
| 119 | return; |
| 120 | } |
| 121 | |
| 122 | terminated = true; |
| 123 | |
| 124 | // tell Timeout to terminate |
| 125 | lock.notify(); |
| 126 | } |
| 127 | } |
| 128 | |
| 129 | // -------------------------------------------------------------- |
| 130 | // private classes |
| 131 | // -------------------------------------------------------------- |
| 132 | private class Timeout implements Runnable { |
| 133 | public void run() { |
| 134 | boolean stopping = false; |
| 135 | |
| 136 | synchronized(lock) { |
| 137 | if (timestamp == 0) timestamp = System.currentTimeMillis(); |
| 138 | logtime("Admin: timeout=",timeout); |
| 139 | logtime("Admin: Timestamp=",timestamp); |
| 140 | |
| 141 | while(!terminated) { |
| 142 | try { |
| 143 | // wait until there is no more job |
| 144 | while(!terminated && currentJobs != 0) { |
| 145 | if (logger.traceOn()) { |
| 146 | logger.trace("Timeout-run", |
| 147 | "Waiting without timeout."); |
| 148 | } |
| 149 | |
| 150 | lock.wait(); |
| 151 | } |
| 152 | |
| 153 | if (terminated) return; |
| 154 | |
| 155 | final long remaining = |
| 156 | timeout - (System.currentTimeMillis() - timestamp); |
| 157 | |
| 158 | logtime("Admin: remaining timeout=",remaining); |
| 159 | |
| 160 | if (remaining > 0) { |
| 161 | |
| 162 | if (logger.traceOn()) { |
| 163 | logger.trace("Timeout-run", |
| 164 | "Waiting with timeout: "+ |
| 165 | remaining + " ms remaining"); |
| 166 | } |
| 167 | |
| 168 | lock.wait(remaining); |
| 169 | } |
| 170 | |
| 171 | if (currentJobs > 0) continue; |
| 172 | |
| 173 | final long elapsed = |
| 174 | System.currentTimeMillis() - timestamp; |
| 175 | logtime("Admin: elapsed=",elapsed); |
| 176 | |
| 177 | if (!terminated && elapsed > timeout) { |
| 178 | if (logger.traceOn()) { |
| 179 | logger.trace("Timeout-run", |
| 180 | "timeout elapsed"); |
| 181 | } |
| 182 | logtime("Admin: timeout elapsed! "+ |
| 183 | elapsed+">",timeout); |
| 184 | // stopping |
| 185 | terminated = true; |
| 186 | |
| 187 | stopping = true; |
| 188 | break; |
| 189 | } |
| 190 | } catch (InterruptedException ire) { |
| 191 | logger.warning("Timeout-run","Unexpected Exception: "+ |
| 192 | ire); |
| 193 | logger.debug("Timeout-run",ire); |
| 194 | return; |
| 195 | } |
| 196 | } |
| 197 | } |
| 198 | |
| 199 | if (stopping) { |
| 200 | if (logger.traceOn()) { |
| 201 | logger.trace("Timeout-run", "Call the doStop."); |
| 202 | } |
| 203 | |
| 204 | doStop(); |
| 205 | } |
| 206 | } |
| 207 | } |
| 208 | |
| 209 | private void logtime(String desc,long time) { |
| 210 | timelogger.trace("synchro",desc+time); |
| 211 | } |
| 212 | |
| 213 | // -------------------------------------------------------------- |
| 214 | // private variables |
| 215 | // -------------------------------------------------------------- |
| 216 | private long timestamp; |
| 217 | |
| 218 | private final int[] lock = new int[0]; |
| 219 | private int currentJobs = 0; |
| 220 | |
| 221 | private long timeout; |
| 222 | |
| 223 | // state issue |
| 224 | private boolean terminated = false; |
| 225 | |
| 226 | private static final ClassLogger logger = |
| 227 | new ClassLogger("javax.management.remote.misc", |
| 228 | "ServerCommunicatorAdmin"); |
| 229 | private static final ClassLogger timelogger = |
| 230 | new ClassLogger("javax.management.remote.timeout", |
| 231 | "ServerCommunicatorAdmin"); |
| 232 | } |