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.
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;
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;
83 /** Default constructor */
85 this.id = nextProcessId++;
88 this.args = new ArrayList<>();
93 * Constructs a new process from the name of a host and his name. The method
94 * function of the process doesn't have argument.
96 * @param hostname The name of the host of the process to create.
97 * @param name The name of the process.
99 * @exception HostNotFoundException if no host with this name exists.
103 public Process(String hostname, String name) throws HostNotFoundException {
104 this(Host.getByName(hostname), name, null);
107 * Constructs a new process from the name of a host and his name. The arguments
108 * of the method function of the process are specified by the parameter args.
110 * @param hostname The name of the host of the process to create.
111 * @param name The name of the process.
112 * @param args The arguments of the main function of the process.
114 * @exception HostNotFoundException if no host with this name exists.
116 * @throws NativeException
119 public Process(String hostname, String name, String[] args) throws HostNotFoundException, NativeException {
120 this(Host.getByName(hostname), name, args);
123 * Constructs a new process from a host and his name. The method function of the
124 * process doesn't have argument.
126 * @param host The host of the process to create.
127 * @param name The name of the process.
130 public Process(Host host, String name) {
131 this(host, name, null);
134 * Constructs a new process from a host and his name, the arguments of here method function are
135 * specified by the parameter args.
137 * @param host The host of the process to create.
138 * @param name The name of the process.
139 * @param args The arguments of main method of the process.
141 public Process(Host host, String name, String[]args) {
145 throw new NullPointerException("Host cannot be NULL");
147 throw new NullPointerException("Process name cannot be NULL");
150 this.args = new ArrayList<>();
152 this.args.addAll(Arrays.asList(args));
155 * Constructs a new process from a host and his name, the arguments of here method function are
156 * specified by the parameter args.
158 * @param host The host of the process to create.
159 * @param name The name of the process.
160 * @param args The arguments of main method of the process.
161 * @param startTime Start time of the process
162 * @param killTime Kill time of the process
165 public Process(Host host, String name, String[]args, double startTime, double killTime) {
166 this(host, name, args);
167 this.startTime = startTime;
168 this.killTime = killTime;
171 * The natively implemented method to create an MSG process.
172 * @param hostName A valid (bound) host where create the process.
174 protected native void create(String hostName) throws HostNotFoundException;
176 * This method kills all running process of the simulation.
178 * @param resetPID Should we reset the PID numbers. A negative number means no reset
179 * and a positive number will be used to set the PID of the next newly
182 * @return The function returns the PID of the next created process.
185 public static native int killAll(int resetPID);
187 /** Simply kills the receiving process.
189 * SimGrid sometimes have issues when you kill processes that are currently communicating and such. We are working on it to fix the issues.
191 public native void kill();
193 /** Suspends the process. See {@link #resume()} to resume it afterward */
194 public native void suspend();
195 /** Resume a process that was suspended by {@link #suspend()}. */
196 public native void resume();
197 /** Tests if a process is suspended.
202 public native boolean isSuspended();
205 * Specify whether the process should restart when its host restarts after a failure
207 * A process naturally stops when its host stops. It starts again only if autoRestart is set to true.
208 * Otherwise, it just disappears when the host stops.
210 public native void setAutoRestart(boolean autoRestart);
211 /** Restarts the process from the beginning */
212 public native void restart();
214 * Returns the name of the process
216 public String getName() {
220 * Returns the host of the process.
221 * @return The host instance of the process.
223 public Host getHost() {
227 * This static method gets a process from a PID.
229 * @param PID The process identifier of the process to get.
231 * @return The process with the specified PID.
233 * @exception NativeException on error in the native SimGrid code
235 public static native Process fromPID(int PID) throws NativeException;
237 * This method returns the PID of the process.
239 * @return The PID of the process.
242 public int getPID() {
246 * This method returns the PID of the parent of a process.
248 * @return The PID of the parent of the process.
251 public int getPPID() {
255 * Returns the value of a given process property.
257 public native String getProperty(String name);
260 * Set the kill time of the process
261 * @param killTime the time when the process is killed
263 public native void setKillTime(double killTime);
266 * This static method returns the currently running process.
268 * @return The current process.
271 public static native Process getCurrentProcess();
273 * Migrates a process to another host.
275 * @param host The host where to migrate the process.
278 public native void migrate(Host host);
280 * Makes the current process sleep until millis millisecondes have elapsed.
281 * You should note that unlike "waitFor" which takes seconds, this method takes milliseconds.
282 * FIXME: Not optimal, maybe we should have two native functions.
283 * @param millis the length of time to sleep in milliseconds.
285 public static void sleep(long millis) throws HostFailureException {
289 * Makes the current process sleep until millis milliseconds and nanos nanoseconds
291 * Unlike {@link #waitFor(double)} which takes seconds, this method takes
292 * milliseconds and nanoseconds.
293 * Overloads Thread.sleep.
294 * @param millis the length of time to sleep in milliseconds.
295 * @param nanos additionnal nanoseconds to sleep.
297 public static native void sleep(long millis, int nanos) throws HostFailureException;
299 * Makes the current process sleep until time seconds have elapsed.
300 * @param seconds The time the current process must sleep.
302 public native void waitFor(double seconds) throws HostFailureException;
304 * This method actually creates and run the process.
305 * It is a noop if the process is already launched.
306 * @throws HostNotFoundException
308 public final void start() throws HostNotFoundException {
311 create(host.getName());
315 /** This method runs the process. Il calls the method function that you must overwrite. */
319 String[] args = null; /* do not fill it before the signal or this.args will be empty */
322 args = new String[this.args.size()];
323 if (!this.args.isEmpty()) {
324 this.args.toArray(args);
328 } catch(MsgException e) {
330 Msg.info("Unexpected behavior. Stopping now");
333 catch(ProcessKilledError pk) {
339 * The main function of the process (to implement).
342 * @throws MsgException
344 public abstract void main(String[]args) throws MsgException;
346 public native void exit();
348 * Class initializer, to initialize various JNI stuff
350 private static native void nativeInit();
352 org.simgrid.NativeLib.nativeInit();
356 * This static method returns the current amount of processes running
358 * @return The count of the running processes
360 public static native int getCount();