2 * JNI interface to C code for MSG.
4 * Copyright 2006-2012 The SimGrid Team.
7 * This program is free software; you can redistribute
8 * it and/or modify it under the terms of the license
9 * (GNU LGPL) which comes with this package.
12 package org.simgrid.msg;
14 import java.io.FileOutputStream;
15 import java.io.InputStream;
16 import java.io.OutputStream;
20 public final class Msg {
21 /* Statically load the library which contains all native functions used in here */
24 /* prefer the version on disk, if existing */
25 System.loadLibrary("SG_java");
26 } catch (UnsatisfiedLinkError e) {
27 /* If not found, unpack the one bundled into the jar file and use it */
32 private static void loadLib (String name) {
33 String Path = "NATIVE/"+System.getProperty("os.name")+"/"+System.getProperty("os.arch")+"/";
35 InputStream in = Msg.class.getClassLoader().getResourceAsStream(Path+filename);
38 filename = "lib"+name+".so";
39 in = Msg.class.getClassLoader().getResourceAsStream(Path+filename);
42 filename = name+".dll";
43 in = Msg.class.getClassLoader().getResourceAsStream(Path+filename);
46 filename = "lib"+name+".dylib";
47 in = Msg.class.getClassLoader().getResourceAsStream(Path+filename);
50 throw new RuntimeException("Cannot find library "+name+" in path "+Path+". Sorry, but this jar does not seem to be usable on your machine.");
52 // Caching the file on disk: desactivated because it could fool the users
53 // if (new File(filename).isFile()) {
54 // // file was already unpacked -- use it directly
55 // System.load(new File(".").getAbsolutePath()+File.separator+filename);
59 // We must write the lib onto the disk before loading it -- stupid operating systems
60 File fileOut = new File(filename);
61 // if (!new File(".").canWrite()) {
62 // System.out.println("Cannot write in ."+File.separator+filename+"; unpacking the library into a temporary file instead");
63 fileOut = File.createTempFile("simgrid-", ".tmp");
64 // don't leak the file on disk, but remove it on JVM shutdown
65 Runtime.getRuntime().addShutdownHook(new Thread(new FileCleaner(fileOut.getAbsolutePath())));
67 // System.out.println("Unpacking SimGrid native library to " + fileOut.getAbsolutePath());
68 OutputStream out = new FileOutputStream(fileOut);
70 /* copy the library in position */
71 byte[] buffer = new byte[4096];
73 while ((bytes_read = in.read(buffer)) != -1) // Read until EOF
74 out.write(buffer, 0, bytes_read);
76 /* close all file descriptors, and load that shit */
79 System.load(fileOut.getAbsolutePath());
80 } catch (Exception e) {
81 System.err.println("Cannot load the bindings to the simgrid library: ");
83 System.err.println("This jar file does not seem to fit your system, sorry");
87 /* A hackish mechanism used to remove the file containing our library when the JVM shuts down */
88 private static class FileCleaner implements Runnable {
89 private String target;
90 public FileCleaner(String name) {
95 new File(target).delete();
96 } catch(Exception e) {
97 System.out.println("Unable to clean temporary file "+target+" during shutdown.");
103 /** Retrieve the simulation time
106 public final static native double getClock();
108 * Issue a debug logging message.
109 * @param s message to log.
111 public final static native void debug(String s);
113 * Issue an verbose logging message.
114 * @param s message to log.
116 public final static native void verb(String s);
118 /** Issue an information logging message
121 public final static native void info(String s);
123 * Issue an warning logging message.
124 * @param s message to log.
126 public final static native void warn(String s);
128 * Issue an error logging message.
129 * @param s message to log.
131 public final static native void error(String s);
133 * Issue an critical logging message.
134 * @param s message to log.
136 public final static native void critical(String s);
138 /*********************************************************************************
139 * Deployment and initialization related functions *
140 *********************************************************************************/
143 * The natively implemented method to initialize a MSG simulation.
145 * @param args The arguments of the command line of the simulation.
149 public final static native void init(String[]args);
152 * Run the MSG simulation.
154 * The simulation is not cleaned afterward (see
155 * {@link #clean()} if you really insist on cleaning the C side), so you can freely
156 * retrieve the informations that you want from the simulation. In particular, retrieving the status
157 * of a process or the current date is perfectly ok.
161 public final static native void run() ;
163 /** This function is useless nowadays, just stop calling it. */
165 public final static void clean(){}
168 * The native implemented method to create the environment of the simulation.
170 * @param platformFile The XML file which contains the description of the environment of the simulation
173 public final static native void createEnvironment(String platformFile);
176 * The method to deploy the simulation.
179 * @param deploymentFile
181 public final static native void deployApplication(String deploymentFile);
183 /** Example launcher. You can use it or provide your own launcher, as you wish
185 * @throws MsgException
187 static public void main(String[]args) throws MsgException {
188 /* initialize the MSG simulation. Must be done before anything else (even logging). */
191 if (args.length < 2) {
192 Msg.info("Usage: Msg platform_file deployment_file");
196 /* Load the platform and deploy the application */
197 Msg.createEnvironment(args[0]);
198 Msg.deployApplication(args[1]);
199 /* Execute the simulation */