| /* UnicastServerRef.java -- |
| Copyright (c) 1996, 1997, 1998, 1999, 2002, 2003, 2004, 2006 |
| Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package gnu.java.rmi.server; |
| |
| import java.io.ObjectInputStream; |
| import java.lang.reflect.Constructor; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Proxy; |
| import java.rmi.Remote; |
| import java.rmi.RemoteException; |
| import java.rmi.server.ObjID; |
| import java.rmi.server.RMIServerSocketFactory; |
| import java.rmi.server.RemoteObjectInvocationHandler; |
| import java.rmi.server.RemoteRef; |
| import java.rmi.server.RemoteServer; |
| import java.rmi.server.RemoteStub; |
| import java.rmi.server.ServerNotActiveException; |
| import java.rmi.server.Skeleton; |
| import java.util.HashSet; |
| import java.util.Hashtable; |
| import java.util.Iterator; |
| |
| /** |
| * This class connects the local, remotely available (exported) object to |
| * the local RMI server that accepts the remote calls. |
| */ |
| public class UnicastServerRef |
| extends UnicastRef |
| { |
| |
| /** |
| * Use GNU Classpath v 0.20 SVUID for interoperability |
| */ |
| private static final long serialVersionUID = - 5585608108300801246L; |
| |
| /** |
| * The class array, defining parameters of the jdk 1.2 RMI stub constructor. |
| */ |
| private static final Class[] stubprototype = new Class[] { RemoteRef.class }; |
| |
| /** |
| * The exported remote object itself. |
| */ |
| Remote myself; // save the remote object itself |
| |
| /** |
| * The skeleton (if any), associated with the exported remote object. |
| */ |
| protected Skeleton skel; |
| |
| /** |
| * The stub, associated with the exported remote object (may be proxy class). |
| */ |
| protected Remote stub; |
| |
| /** |
| * The method table (RMI hash code to method) of the methods of the |
| * exported object. |
| */ |
| protected Hashtable methods = new Hashtable(); |
| |
| /** |
| * Used by serialization. |
| */ |
| UnicastServerRef() |
| { |
| } |
| |
| public UnicastServerRef(ObjID id, int port, RMIServerSocketFactory ssf) |
| throws RemoteException |
| { |
| super(id); |
| manager = UnicastConnectionManager.getInstance(port, ssf); |
| } |
| |
| /** |
| * Export the object and return its remote stub. The method tries to locate |
| * existing stubs and skeletons. If this fails, the method instantiates the |
| * proxy stub class. |
| * |
| * Stubs and skeletons are always ignored (even if present) if the |
| * java.rmi.server.ignoreStubClasses property is set to true. |
| * |
| * @param obj the object being exported. |
| * @return the stub (existing class or proxy) of the exported object. |
| * @throws RemoteException if the export failed due any reason |
| */ |
| public Remote exportObject(Remote obj) throws RemoteException |
| { |
| if (myself == null) |
| { |
| myself = obj; |
| // Save it to server manager, to let client calls in the same VM to |
| // issue local call |
| manager.serverobj = obj; |
| |
| String ignoreStubs; |
| |
| ClassLoader loader =obj.getClass().getClassLoader(); |
| |
| // Stubs are always searched for the bootstrap classes that may have |
| // obsolete pattern and may still need also skeletons. |
| if (loader==null) |
| ignoreStubs = "false"; |
| else |
| ignoreStubs = System.getProperty("java.rmi.server.ignoreStubClasses", |
| "false"); |
| |
| if (! ignoreStubs.equals("true")) |
| { |
| // Find and install the stub |
| Class cls = obj.getClass(); |
| |
| // where ist the _Stub? (check superclasses also) |
| Class expCls = findStubSkelClass(cls); |
| |
| if (expCls != null) |
| { |
| stub = (RemoteStub) getHelperClass(expCls, "_Stub"); |
| // Find and install the skeleton (if there is one) |
| skel = (Skeleton) getHelperClass(expCls, "_Skel"); |
| } |
| } |
| |
| if (stub == null) |
| stub = createProxyStub(obj.getClass(), this); |
| |
| // Build hash of methods which may be called. |
| buildMethodHash(obj.getClass(), true); |
| |
| // Export it. |
| UnicastServer.exportObject(this); |
| } |
| |
| return stub; |
| } |
| |
| /** |
| * Get the stub (actual class or proxy) of the exported remote object. |
| * |
| * @return the remote stub (null if exportObject has not been called). |
| */ |
| public Remote getStub() |
| { |
| return stub; |
| } |
| |
| /** |
| * Unexport the object (remove methods from the method hashcode table |
| * and call UnicastServer.unexportObject. |
| * |
| * @param obj the object being unexported |
| * @param force passed to the UnicastServer.unexportObject. |
| * @return value, returned by the UnicastServer.unexportObject. |
| */ |
| public boolean unexportObject(Remote obj, boolean force) |
| { |
| // Remove all hashes of methods which may be called. |
| buildMethodHash(obj.getClass(), false); |
| return UnicastServer.unexportObject(this, force); |
| } |
| |
| /** |
| * Return the class in the hierarchy for that the stub class is defined. |
| * The Subs/Skels might not there for the actual class, but maybe for one of |
| * the superclasses. |
| * |
| * @return the class having stub defined, null if none. |
| */ |
| protected Class findStubSkelClass(Class startCls) |
| { |
| Class cls = startCls; |
| |
| while (true) |
| { |
| try |
| { |
| String stubClassname = cls.getName() + "_Stub"; |
| ClassLoader cl = cls.getClassLoader(); |
| Class scls = cl == null ? Class.forName(stubClassname) |
| : cl.loadClass(stubClassname); |
| return cls; // found it |
| } |
| catch (ClassNotFoundException e) |
| { |
| Class superCls = cls.getSuperclass(); |
| if (superCls == null |
| || superCls == java.rmi.server.UnicastRemoteObject.class) |
| { |
| return null; |
| } |
| cls = superCls; |
| } |
| } |
| } |
| |
| /** |
| * Get the helper (assisting) class with the given type. |
| * |
| * @param cls the class, for that the helper class is requested. This class |
| * and the requested helper class must share the same class loader. |
| * |
| * @param type the type of the assisting helper. The only currently supported |
| * non deprecated value is "_Stub" (load jdk 1.1 or 1.2 RMI stub). Another |
| * (deprecated) value is "_Skel" (load skeleton). |
| * |
| * @return the instantiated instance of the helper class or null if the |
| * helper class cannot be found or instantiated. |
| */ |
| protected Object getHelperClass(Class cls, String type) |
| { |
| try |
| { |
| String classname = cls.getName(); |
| ClassLoader cl = cls.getClassLoader(); |
| Class scls = cl == null ? Class.forName(classname + type) |
| : cl.loadClass(classname + type); |
| if (type.equals("_Stub")) |
| { |
| try |
| { |
| // JDK 1.2 stubs |
| Constructor con = scls.getConstructor(stubprototype); |
| return (con.newInstance(new Object[] { this })); |
| } |
| catch (NoSuchMethodException e) |
| { |
| } |
| catch (InstantiationException e) |
| { |
| } |
| catch (IllegalAccessException e) |
| { |
| } |
| catch (IllegalArgumentException e) |
| { |
| } |
| catch (InvocationTargetException e) |
| { |
| } |
| // JDK 1.1 stubs |
| RemoteStub stub = (RemoteStub) scls.newInstance(); |
| UnicastRemoteStub.setStubRef(stub, this); |
| return (stub); |
| } |
| else |
| { |
| // JDK 1.1 skel |
| return (scls.newInstance()); |
| } |
| } |
| catch (ClassNotFoundException e) |
| { |
| } |
| catch (InstantiationException e) |
| { |
| } |
| catch (IllegalAccessException e) |
| { |
| } |
| return (null); |
| } |
| |
| public String getClientHost() throws ServerNotActiveException |
| { |
| return RemoteServer.getClientHost(); |
| } |
| |
| /** |
| * Build the method has code table and put it into {@link #methods} |
| * (mapping RMI hashcode tos method). The same method is used to remove |
| * the table. |
| * |
| * @param cls the class for that the method table is built. |
| * @param build if true, the class methods are added to the table. If |
| * false, they are removed from the table. |
| */ |
| protected void buildMethodHash(Class cls, boolean build) |
| { |
| Method[] meths = cls.getMethods(); |
| for (int i = 0; i < meths.length; i++) |
| { |
| /* Don't need to include any java.xxx related stuff */ |
| if (meths[i].getDeclaringClass().getName().startsWith("java.")) |
| { |
| continue; |
| } |
| long hash = RMIHashes.getMethodHash(meths[i]); |
| if (build) |
| methods.put(new Long(hash), meths[i]); |
| else |
| methods.remove(new Long(hash)); |
| // System.out.println("meth = " + meths[i] + ", hash = " + hash); |
| } |
| } |
| |
| Class getMethodReturnType(int method, long hash) throws Exception |
| { |
| if (method == - 1) |
| { |
| Method meth = (Method) methods.get(new Long(hash)); |
| return meth.getReturnType(); |
| } |
| else |
| return null; |
| } |
| |
| /** |
| * This method is called from the {@link UnicastServer#incomingMessageCall} |
| * to deliver the remote call to this object. |
| */ |
| public Object incomingMessageCall(UnicastConnection conn, int method, |
| long hash) throws Exception |
| { |
| // System.out.println("method = " + method + ", hash = " + hash); |
| // If method is -1 then this is JDK 1.2 RMI - so use the hash |
| // to locate the method |
| if (method == - 1) |
| { |
| Method meth = (Method) methods.get(new Long(hash)); |
| // System.out.println("class = " + myself.getClass() + ", meth = " + |
| // meth); |
| if (meth == null) |
| { |
| throw new NoSuchMethodException( |
| myself.getClass().getName()+" hash "+hash); |
| } |
| |
| ObjectInputStream in = conn.getObjectInputStream(); |
| int nrargs = meth.getParameterTypes().length; |
| Object[] args = new Object[nrargs]; |
| for (int i = 0; i < nrargs; i++) |
| { |
| /** |
| * For debugging purposes - we don't handle CodeBases quite right so |
| * we don't always find the stubs. This lets us know that. |
| */ |
| try |
| { |
| // need to handle primitive types |
| args[i] = ((RMIObjectInputStream) in) |
| .readValue(meth.getParameterTypes()[i]); |
| |
| } |
| catch (Exception t) |
| { |
| t.printStackTrace(); |
| throw t; |
| } |
| } |
| //We must reinterpret the exception thrown by meth.invoke() |
| //return (meth.invoke(myself, args)); |
| Object ret = null; |
| try |
| { |
| ret = meth.invoke(myself, args); |
| } |
| catch (InvocationTargetException e) |
| { |
| Throwable cause = e.getTargetException(); |
| if (cause instanceof Exception) |
| { |
| throw (Exception) cause; |
| } |
| else if (cause instanceof Error) |
| { |
| throw (Error) cause; |
| } |
| else |
| { |
| throw new Error( |
| "The remote method threw a java.lang.Throwable that"+ |
| " is neither java.lang.Exception nor java.lang.Error.", |
| e); |
| } |
| } |
| return ret; |
| } |
| // Otherwise this is JDK 1.1 style RMI - we find the skeleton |
| // and invoke it using the method number. We wrap up our |
| // connection system in a UnicastRemoteCall so it appears in a |
| // way the Skeleton can handle. |
| else |
| { |
| if (skel == null) |
| throw new NoSuchMethodException("JDK 1.1 call - Skeleton required"); |
| |
| UnicastRemoteCall call = new UnicastRemoteCall(conn); |
| skel.dispatch(myself, call, method, hash); |
| if (! call.isReturnValue()) |
| return RMIVoidValue.INSTANCE; |
| else |
| return (call.returnValue()); |
| } |
| } |
| |
| /** |
| * Create the 1.2 proxy stub in the case when the pre-generated stub is not |
| * available of the system is explicitly instructed to use proxy stubs. |
| * |
| * @param stubFor the class for that the proxy class must be constructed. |
| * @param reference the remote reference, used to find the given object |
| * |
| * @return the applicable proxy stub. |
| * |
| * @author Audrius Meskauskas (AudriusA@Bioinformatics.org) |
| */ |
| Remote createProxyStub(Class stubFor, RemoteRef reference) |
| { |
| // Collect all interfaces, implemented by stubFor and derived from |
| // Remote (also Remote itself): |
| HashSet interfaces = new HashSet(); |
| Class c = stubFor; |
| Class[] intfs; |
| |
| while (c != null) |
| { |
| intfs = c.getInterfaces(); |
| for (int i = 0; i < intfs.length; i++) |
| { |
| if (Remote.class.isAssignableFrom(intfs[i])) |
| interfaces.add(intfs[i]); |
| } |
| c = c.getSuperclass(); |
| } |
| |
| intfs = new Class[interfaces.size()]; |
| Iterator it = interfaces.iterator(); |
| |
| for (int i = 0; i < intfs.length; i++) |
| intfs[i] = (Class) it.next(); |
| |
| RemoteObjectInvocationHandler handler = |
| new RemoteObjectInvocationHandler(reference); |
| |
| Object proxy = |
| Proxy.newProxyInstance(stubFor.getClassLoader(), intfs, handler); |
| |
| return (Remote) proxy; |
| } |
| |
| |
| } |
| |
| |