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POHow to automatically copy data to new RMI threads?
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  1. POHow to automatically copy data to new RMI threads?
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    copied!<p>I am adapting a little rmi client-server application. I have written several things :</p> <pre><code>HelloInterface -&gt; A Hello World interface for RMI Server -&gt; The server app' Client -&gt; The client app' </code></pre> <p>Nothing special, but... I have put my hands in a new RMISecurityManager, which calls a JNI method and checks the permission for a separate user:</p> <pre><code>package rmi; import java.rmi.RMISecurityManager; import java.io.*; public class NativeRMISecurityManager extends RMISecurityManager { private boolean unix; protected static ThreadLocal user = new ThreadLocal(); /* * On interdit l'utilisation du constructeur par defaut * pour obliger l'utilisation du constructeur avec user. */ private NativeRMISecurityManager() { super(); } public NativeRMISecurityManager (final String user) { super(); String OS = System.getProperty("os.name").toLowerCase(); unix = (OS.compareTo("windows") != 0); /* Assume that if not * windows, then "UNIX/POSIX" */ /* * ThreadLocal's user : Each thread is considered * to have different access rights to the machine */ NativeRMISecurityManager.user.set(user); if (!unix) { System.out.println("Systeme : "+OS); } } public void checkRead(String file) { super.checkRead(file); /* * If we are on a **IX platform we want to check that * the _user_ has access rights. */ if (unix) { String str_user = (String)NativeRMISecurityManager.user.get(); if (file == null) { throw new SecurityException("file = NULL !!!"); } if (str_user == null) { throw new SecurityException("user = NULL in the ThreadLocal!!!"); } int ret = c_checkRead( file, str_user ); if (ret != 0) { throw new SecurityException("Access error: " + file); } } } public native int c_checkRead(String file, String user); } </code></pre> <p>In the Server class I'm doing that : </p> <pre><code>String user = "my_user"; System.setSecurityManager(new NativeRMISecurityManager(user)); </code></pre> <p>This class seems to work in the Server's main thread. Now the problem is when I try and connect to that Server class and lookup the Registry. I get that exception : </p> <pre><code>Exception in thread "RMI TCP Connection(1)-192.168.42.207" java.lang.ExceptionInInitializerError at sun.rmi.transport.StreamRemoteCall.getInputStream(StreamRemoteCall.java:111) at sun.rmi.transport.Transport.serviceCall(Transport.java:118) at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:466) at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:707) at java.lang.Thread.run(Thread.java:595) Caused by: java.lang.SecurityException: user = NULL dans le ThreadLocal!!! at rmi.NativeRMISecurityManager.checkRead(NativeRMISecurityManager.java:62) at java.io.File.exists(File.java:700) at java.lang.ClassLoader$3.run(ClassLoader.java:1689) at java.security.AccessController.doPrivileged(Native Method) at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1686) at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1668) at java.lang.Runtime.loadLibrary0(Runtime.java:822) at java.lang.System.loadLibrary(System.java:993) at sun.security.action.LoadLibraryAction.run(LoadLibraryAction.java:50) at java.security.AccessController.doPrivileged(Native Method) at sun.rmi.server.MarshalInputStream.&lt;clinit&gt;(MarshalInputStream.java:97) ... 5 more </code></pre> <p>IMHO the meaning of this is that a thread is (implicitly) created and gets the NativeRMISecurityManager as its default SecurityManager.</p> <p>Would somebody have any advice concerning that ?</p>
 

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