libjava/gnu/java/rmi/server/UnicastServer.java

   1 /*
   2   Copyright (c) 1996, 1997, 1998, 1999, 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38 package gnu.java.rmi.server;
  39
  40 import java.io.DataInputStream;
  41 import java.io.DataOutputStream;
  42 import java.io.ObjectInputStream;
  43 import java.io.ObjectOutputStream;
  44 import java.io.IOException;
  45 import java.net.InetAddress;
  46 import java.util.Hashtable;
  47 import java.net.UnknownHostException;
  48 import java.rmi.Remote;
  49 import java.rmi.server.ObjID;
  50 import java.rmi.server.UnicastRemoteObject;
  51 import java.rmi.server.UID;
  52 import java.rmi.server.RemoteRef;
  53 import java.rmi.RemoteException;
  54 import java.rmi.NoSuchObjectException;
  55 import gnu.java.rmi.dgc.DGCImpl;
  56
  57 public class UnicastServer
  58         implements ProtocolConstants {
  59
  60 static private Hashtable objects = new Hashtable();  //mapping OBJID to server ref
  61 static private Hashtable refcache = new Hashtable(); //mapping obj itself to server ref
  62 static private DGCImpl dgc;
  63
  64 public static void exportObject(UnicastServerRef obj) {
  65         startDGC();
  66         objects.put(obj.objid, obj);
  67         refcache.put(obj.myself, obj);
  68         obj.manager.startServer();
  69 }
  70
  71 // FIX ME: I haven't handle force parameter
  72 public static boolean unexportObject(UnicastServerRef obj, boolean force) {
  73         objects.remove(obj.objid);
  74         refcache.remove(obj.myself);
  75         obj.manager.stopServer();
  76         return true;
  77 }
  78
  79 public static UnicastServerRef getExportedRef(Remote remote){
  80     return (UnicastServerRef)refcache.get(remote);
  81 }
  82
  83 private static synchronized void startDGC() {
  84         if (dgc == null) {
  85                 try {
  86                         dgc = new DGCImpl();
  87                         // Changed DGCImpl to inherit UnicastServerRef directly
  88                         //((UnicastServerRef)dgc.getRef()).exportObject(dgc);
  89                         dgc.exportObject(dgc);
  90                 }
  91                 catch (RemoteException e) {
  92                         e.printStackTrace();
  93                 }
  94         }
  95 }
  96
  97 public static void dispatch(UnicastConnection conn) throws Exception {
  98         switch (conn.getDataInputStream().readUnsignedByte()) {
  99         case MESSAGE_CALL:
 100                 incomingMessageCall(conn);
 101                 break;
 102         default:
 103                 throw new Exception("bad method type");
 104         }
 105 }
 106
 107 private static void incomingMessageCall(UnicastConnection conn) throws IOException {
 108         ObjectInputStream in = conn.getObjectInputStream();
 109
 110         ObjID objid = ObjID.read(in);
 111         int method = in.readInt();
 112         long hash = in.readLong();
 113
 114 //System.out.println("ObjID: " + objid + ", method: " + method + ", hash: " + hash);
 115
 116         // Use the objid to locate the relevant UnicastServerRef
 117         UnicastServerRef uref = (UnicastServerRef)objects.get(objid);
 118         Object returnval;
 119         int returncode = RETURN_ACK;
 120         // returnval is from Method.invoke(), so we must check the return class to see
 121         // if it's primitive type
 122         Class returncls = null;
 123         if (uref != null) {
 124                 try {
 125                         // Dispatch the call to it.
 126                         returnval = uref.incomingMessageCall(conn, method, hash);
 127                         returncls = uref.getMethodReturnType(method, hash);
 128                 }
 129                 catch (Exception e) {
 130                         returnval = e;
 131                         returncode = RETURN_NACK;
 132                 }
 133         }
 134         else {
 135                 returnval = new NoSuchObjectException("");
 136                 returncode = RETURN_NACK;
 137         }
 138
 139         conn.getDataOutputStream().writeByte(MESSAGE_CALL_ACK);
 140
 141         ObjectOutputStream out = conn.getObjectOutputStream();
 142
 143         out.writeByte(returncode);
 144         (new UID()).write(out);
 145         if(returnval != null && returncls != null)
 146             ((RMIObjectOutputStream)out).writeValue(returnval, returncls);
 147         else if (!(returnval instanceof RMIVoidValue))
 148             out.writeObject(returnval);
 149
 150         out.flush();
 151 }
 152
 153 }