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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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package sun.rmi.transport;

import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import java.rmi.Remote;
import java.rmi.RemoteException;
import java.rmi.server.ObjID;
import java.rmi.server.RMIClientSocketFactory;
import java.rmi.server.RMIServerSocketFactory;
import java.util.Arrays;
import sun.rmi.transport.tcp.TCPEndpoint;

NOTE: There is a JDK-internal dependency on the existence of this class and its getClientSocketFactory method in the implementation of javax.management.remote.rmi.RMIConnector.
/** * NOTE: There is a JDK-internal dependency on the existence of this * class and its getClientSocketFactory method in the implementation * of javax.management.remote.rmi.RMIConnector. **/
public class LiveRef implements Cloneable {
wire representation for the object
/** wire representation for the object*/
private final Endpoint ep; private final ObjID id;
cached connection service for the object
/** cached connection service for the object */
private transient Channel ch;
flag to indicate whether this ref specifies a local server or is a ref for a remote object (surrogate)
/** flag to indicate whether this ref specifies a local server or * is a ref for a remote object (surrogate) */
private final boolean isLocal;
Construct a "well-known" live reference to a remote object
Params:
  • isLocalServer – If true, indicates this ref specifies a local server in this address space; if false, the ref is for a remote object (hence a surrogate or proxy) in another address space.
/** * Construct a "well-known" live reference to a remote object * @param isLocalServer If true, indicates this ref specifies a local * server in this address space; if false, the ref is for a remote * object (hence a surrogate or proxy) in another address space. */
public LiveRef(ObjID objID, Endpoint endpoint, boolean isLocal) { ep = endpoint; id = objID; this.isLocal = isLocal; }
Construct a new live reference for a server object in the local address space.
/** * Construct a new live reference for a server object in the local * address space. */
public LiveRef(int port) { this((new ObjID()), port); }
Construct a new live reference for a server object in the local address space, to use sockets of the specified type.
/** * Construct a new live reference for a server object in the local * address space, to use sockets of the specified type. */
public LiveRef(int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf) { this((new ObjID()), port, csf, ssf); }
Construct a new live reference for a "well-known" server object in the local address space.
/** * Construct a new live reference for a "well-known" server object * in the local address space. */
public LiveRef(ObjID objID, int port) { this(objID, TCPEndpoint.getLocalEndpoint(port), true); }
Construct a new live reference for a "well-known" server object in the local address space, to use sockets of the specified type.
/** * Construct a new live reference for a "well-known" server object * in the local address space, to use sockets of the specified type. */
public LiveRef(ObjID objID, int port, RMIClientSocketFactory csf, RMIServerSocketFactory ssf) { this(objID, TCPEndpoint.getLocalEndpoint(port, csf, ssf), true); }
Return a shallow copy of this ref.
/** * Return a shallow copy of this ref. */
public Object clone() { try { LiveRef newRef = (LiveRef) super.clone(); return newRef; } catch (CloneNotSupportedException e) { throw new InternalError(e.toString(), e); } }
Return the port number associated with this ref.
/** * Return the port number associated with this ref. */
public int getPort() { return ((TCPEndpoint) ep).getPort(); }
Return the client socket factory associated with this ref. NOTE: There is a JDK-internal dependency on the existence of this method in the implementation of javax.management.remote.rmi.RMIConnector.
/** * Return the client socket factory associated with this ref. * * NOTE: There is a JDK-internal dependency on the existence of * this method in the implementation of * javax.management.remote.rmi.RMIConnector. **/
public RMIClientSocketFactory getClientSocketFactory() { return ((TCPEndpoint) ep).getClientSocketFactory(); }
Return the server socket factory associated with this ref.
/** * Return the server socket factory associated with this ref. */
public RMIServerSocketFactory getServerSocketFactory() { return ((TCPEndpoint) ep).getServerSocketFactory(); }
Export the object to accept incoming calls.
/** * Export the object to accept incoming calls. */
public void exportObject(Target target) throws RemoteException { ep.exportObject(target); } public Channel getChannel() throws RemoteException { if (ch == null) { ch = ep.getChannel(); } return ch; } public ObjID getObjID() { return id; } Endpoint getEndpoint() { return ep; } public String toString() { String type; if (isLocal) type = "local"; else type = "remote"; return "[endpoint:" + ep + "(" + type + ")," + "objID:" + id + "]"; } public int hashCode() { return id.hashCode(); } public boolean equals(Object obj) { if (obj != null && obj instanceof LiveRef) { LiveRef ref = (LiveRef) obj; return (ep.equals(ref.ep) && id.equals(ref.id) && isLocal == ref.isLocal); } else { return false; } } public boolean remoteEquals(Object obj) { if (obj != null && obj instanceof LiveRef) { LiveRef ref = (LiveRef) obj; TCPEndpoint thisEp = ((TCPEndpoint) ep); TCPEndpoint refEp = ((TCPEndpoint) ref.ep); RMIClientSocketFactory thisClientFactory = thisEp.getClientSocketFactory(); RMIClientSocketFactory refClientFactory = refEp.getClientSocketFactory(); /** * Fix for 4254103: LiveRef.remoteEquals should not fail * if one of the objects in the comparison has a null * server socket. Comparison should only consider the * following criteria: * * hosts, ports, client socket factories and object IDs. */ if (thisEp.getPort() != refEp.getPort() || !thisEp.getHost().equals(refEp.getHost())) { return false; } if ((thisClientFactory == null) ^ (refClientFactory == null)) { return false; } if ((thisClientFactory != null) && !((thisClientFactory.getClass() == refClientFactory.getClass()) && (thisClientFactory.equals(refClientFactory)))) { return false; } return (id.equals(ref.id)); } else { return false; } } public void write(ObjectOutput out, boolean useNewFormat) throws IOException { boolean isResultStream = false; if (out instanceof ConnectionOutputStream) { ConnectionOutputStream stream = (ConnectionOutputStream) out; isResultStream = stream.isResultStream(); /* * Ensure that referential integrity is not broken while * this LiveRef is in transit. If it is being marshalled * as part of a result, it may not otherwise be strongly * reachable after the remote call has completed; even if * it is being marshalled as part of an argument, the VM * may determine that the reference on the stack is no * longer reachable after marshalling (see 6181943)-- * therefore, tell the stream to save a reference until a * timeout expires or, for results, a DGCAck message has * been received from the caller, or for arguments, the * remote call has completed. For a "local" LiveRef, save * a reference to the impl directly, because the impl is * not reachable from the LiveRef (see 4114579); * otherwise, save a reference to the LiveRef, for the * client-side DGC to watch over. (Also see 4017232.) */ if (isLocal) { ObjectEndpoint oe = new ObjectEndpoint(id, ep.getInboundTransport()); Target target = ObjectTable.getTarget(oe); if (target != null) { Remote impl = target.getImpl(); if (impl != null) { stream.saveObject(impl); } } } else { stream.saveObject(this); } } // All together now write out the endpoint, id, and flag // (need to choose whether or not to use old JDK1.1 endpoint format) if (useNewFormat) { ((TCPEndpoint) ep).write(out); } else { ((TCPEndpoint) ep).writeHostPortFormat(out); } id.write(out); out.writeBoolean(isResultStream); } public static LiveRef read(ObjectInput in, boolean useNewFormat) throws IOException, ClassNotFoundException { Endpoint ep; ObjID id; // Now read in the endpoint, id, and result flag // (need to choose whether or not to read old JDK1.1 endpoint format) if (useNewFormat) { ep = TCPEndpoint.read(in); } else { ep = TCPEndpoint.readHostPortFormat(in); } id = ObjID.read(in); boolean isResultStream = in.readBoolean(); LiveRef ref = new LiveRef(id, ep, false); if (in instanceof ConnectionInputStream) { ConnectionInputStream stream = (ConnectionInputStream)in; // save ref to send "dirty" call after all args/returns // have been unmarshaled. stream.saveRef(ref); if (isResultStream) { // set flag in stream indicating that remote objects were // unmarshaled. A DGC ack should be sent by the transport. stream.setAckNeeded(); } } else { DGCClient.registerRefs(ep, Arrays.asList(new LiveRef[] { ref })); } return ref; } }