1 /* Copyright (c) 2006-2014. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
7 package org.simgrid.msg;
9 import java.util.Arrays;
10 import java.util.ArrayList;
13 * A process may be defined as a code, with some private data, executing
14 * in a location (host). All the process used by your simulation must be
15 * declared in the deployment file (XML format).
16 * To create your own process you must inherit your own process from this
17 * class and override the method "main()". For example if you want to use
18 * a process named Slave proceed as it :
20 * (1) import the class Process of the package simgrid.msg
21 * import simgrid.msg.Process;
23 * public class Slave extends simgrid.msg.Process {
25 * (2) Override the method function
28 * public void main(String[] args) {
29 * System.out.println("Hello MSG");
33 * The name of your process must be declared in the deployment file of your simulation.
34 * For the example, for the previous process Slave this file must contains a line :
35 * <process host="Maxims" function="Slave"/>, where Maxims is the host of the process
36 * Slave. All the process of your simulation are automatically launched and managed by Msg.
37 * A process use tasks to simulate communications or computations with another process.
38 * For more information see Task. For more information on host concept
43 public abstract class Process implements Runnable {
45 * This attribute represents a bind between a java process object and
46 * a native process. Even if this attribute is public you must never
47 * access to it. It is set automatically during the build of the object.
49 private long bind = 0;
50 /** Indicates if the process is started */
53 * Even if this attribute is public you must never access to it.
54 * It is used to compute the id of an MSG process.
56 private static long nextProcessId = 0;
59 * Even if this attribute is public you must never access to it.
60 * It is compute automatically during the creation of the object.
61 * The native functions use this identifier to synchronize the process.
65 /** Time at which the process should be created */
66 protected double startTime = 0;
67 /** Time at which the process should be killed.
69 * Set at creation, and used internally by SimGrid
71 private double killTime = -1;
73 private String name = null;
76 private int ppid = -1;
77 private Host host = null;
79 /** The arguments of the method function of the process. */
80 private ArrayList<String> args = new ArrayList<>();
83 /** Default constructor */
85 this.id = nextProcessId++;
89 * Constructs a new process from the name of a host and his name. The method
90 * function of the process doesn't have argument.
92 * @param hostname The name of the host of the process to create.
93 * @param name The name of the process.
95 * @exception HostNotFoundException if no host with this name exists.
99 public Process(String hostname, String name) throws HostNotFoundException {
100 this(Host.getByName(hostname), name, null);
103 * Constructs a new process from the name of a host and his name. The arguments
104 * of the method function of the process are specified by the parameter args.
106 * @param hostname The name of the host of the process to create.
107 * @param name The name of the process.
108 * @param args The arguments of the main function of the process.
110 * @exception HostNotFoundException if no host with this name exists.
112 * @throws NativeException
115 public Process(String hostname, String name, String[] args) throws HostNotFoundException, NativeException {
116 this(Host.getByName(hostname), name, args);
119 * Constructs a new process from a host and his name. The method function of the
120 * process doesn't have argument.
122 * @param host The host of the process to create.
123 * @param name The name of the process.
126 public Process(Host host, String name) {
127 this(host, name, null);
130 * Constructs a new process from a host and his name, the arguments of here method function are
131 * specified by the parameter args.
133 * @param host The host of the process to create.
134 * @param name The name of the process.
135 * @param args The arguments of main method of the process.
137 public Process(Host host, String name, String[]args) {
141 throw new NullPointerException("Host cannot be NULL");
143 throw new NullPointerException("Process name cannot be NULL");
146 this.args = new ArrayList<>();
148 this.args.addAll(Arrays.asList(args));
151 * Constructs a new process from a host and his name, the arguments of here method function are
152 * specified by the parameter args.
154 * @param host The host of the process to create.
155 * @param name The name of the process.
156 * @param args The arguments of main method of the process.
157 * @param startTime Start time of the process
158 * @param killTime Kill time of the process
161 public Process(Host host, String name, String[]args, double startTime, double killTime) {
162 this(host, name, args);
163 this.startTime = startTime;
164 this.killTime = killTime;
167 * The natively implemented method to create an MSG process.
168 * @param hostName A valid (bound) host where create the process.
170 protected native void create(String hostName) throws HostNotFoundException;
172 * This method kills all running process of the simulation.
174 * @param resetPID Should we reset the PID numbers. A negative number means no reset
175 * and a positive number will be used to set the PID of the next newly
178 * @return The function returns the PID of the next created process.
181 public static native int killAll(int resetPID);
183 /** Simply kills the receiving process.
185 * SimGrid sometimes have issues when you kill processes that are currently communicating and such. We are working on it to fix the issues.
187 public native void kill();
188 public static void kill(Process p) {
192 /** Suspends the process. See {@link #resume()} to resume it afterward */
193 public native void suspend();
194 /** Resume a process that was suspended by {@link #suspend()}. */
195 public native void resume();
196 /** Tests if a process is suspended.
201 public native boolean isSuspended();
203 /** Yield the current process. All other processes that are ready at the same timestamp will be executed first */
204 public native static void yield();
207 * Specify whether the process should restart when its host restarts after a failure
209 * A process naturally stops when its host stops. It starts again only if autoRestart is set to true.
210 * Otherwise, it just disappears when the host stops.
212 public native void setAutoRestart(boolean autoRestart);
213 /** Restarts the process from the beginning */
214 public native void restart();
216 * Returns the name of the process
218 public String getName() {
222 * Returns the host of the process.
223 * @return The host instance of the process.
225 public Host getHost() {
229 * This static method gets a process from a PID.
231 * @param PID The process identifier of the process to get.
233 * @return The process with the specified PID.
235 * @exception NativeException on error in the native SimGrid code
237 public static native Process fromPID(int PID) throws NativeException;
239 * This method returns the PID of the process.
241 * @return The PID of the process.
244 public int getPID() {
248 * This method returns the PID of the parent of a process.
250 * @return The PID of the parent of the process.
253 public int getPPID() {
257 * Returns the value of a given process property.
259 public native String getProperty(String name);
262 * Set the kill time of the process
263 * @param killTime the time when the process is killed
265 public native void setKillTime(double killTime);
268 * This static method returns the currently running process.
270 * @return The current process.
273 public static native Process getCurrentProcess();
275 * Migrates a process to another host.
277 * @param host The host where to migrate the process.
280 public native void migrate(Host host);
282 * Makes the current process sleep until millis milliseconds have elapsed.
283 * You should note that unlike "waitFor" which takes seconds, this method takes milliseconds.
284 * FIXME: Not optimal, maybe we should have two native functions.
285 * @param millis the length of time to sleep in milliseconds.
287 public static void sleep(long millis) throws HostFailureException {
291 * Makes the current process sleep until millis milliseconds and nanos nanoseconds
293 * Unlike {@link #waitFor(double)} which takes seconds, this method takes
294 * milliseconds and nanoseconds.
295 * Overloads Thread.sleep.
296 * @param millis the length of time to sleep in milliseconds.
297 * @param nanos additional nanoseconds to sleep.
299 public static native void sleep(long millis, int nanos) throws HostFailureException;
301 * Makes the current process sleep until time seconds have elapsed.
302 * @param seconds The time the current process must sleep.
304 public native void waitFor(double seconds) throws HostFailureException;
306 * This method actually creates and run the process.
307 * It is a noop if the process is already launched.
308 * @throws HostNotFoundException
310 public final void start() throws HostNotFoundException {
313 create(host.getName());
317 /** This method runs the process. Il calls the method function that you must overwrite. */
321 String[] args = null; /* do not fill it before the signal or this.args will be empty */
324 args = new String[this.args.size()];
325 if (!this.args.isEmpty()) {
326 this.args.toArray(args);
331 catch(MsgException e) {
333 Msg.info("Unexpected behavior. Stopping now");
336 catch(ProcessKilledError pk) {
337 /* The process was killed before its end. With a kill() or something. */
342 * The main function of the process (to implement).
345 * @throws MsgException
347 public abstract void main(String[]args) throws MsgException;
349 /** Stops the execution of the current actor */
354 * Class initializer, to initialize various JNI stuff
356 private static native void nativeInit();
358 org.simgrid.NativeLib.nativeInit();
362 * This static method returns the current amount of processes running
364 * @return The count of the running processes
366 public static native int getCount();