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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
 *
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.rmi.transport;

import java.io.IOException;
import java.rmi.server.UID;
import sun.rmi.server.MarshalOutputStream;

Special stream to keep track of refs being marshaled as return
results to determine whether a special ack needs to be sent
to the distributed collector.
Author:
Ann Wollrath/**
 * Special stream to keep track of refs being marshaled as return
 * results to determine whether a special ack needs to be sent
 * to the distributed collector.
 *
 * @author Ann Wollrath
 */
class ConnectionOutputStream extends MarshalOutputStream {

    
connection associated with ConnectionOutputStream /** connection associated with ConnectionOutputStream */
    private final Connection conn;
    
indicates whether output stream is used to marshal results /** indicates whether output stream is used to marshal results */
    private final boolean resultStream;
    
identifier for gc ack/** identifier for gc ack*/
    private final UID ackID;

    
to store refs to returned remote object until DGC ack is received /** to store refs to returned remote object until DGC ack is received */
    private DGCAckHandler dgcAckHandler = null;

    
Constructs an marshal output stream using the underlying
stream associated with the connection, the parameter c.
Params:
c – is the Connection object associated with the
ConnectionOutputStream object being constructed
resultStream – indicates whether this stream is used
to marshal return results/**
     * Constructs an marshal output stream using the underlying
     * stream associated with the connection, the parameter c.
     * @param c is the Connection object associated with the
     * ConnectionOutputStream object being constructed
     * @param resultStream indicates whether this stream is used
     * to marshal return results
     */
    ConnectionOutputStream(Connection conn, boolean resultStream)
        throws IOException
    {
        super(conn.getOutputStream());
        this.conn = conn;
        this.resultStream = resultStream;
        ackID = resultStream ? new UID() : null;
    }

    void writeID() throws IOException {
        assert resultStream;
        ackID.write(this);
    }

    
Returns true if this output stream is used to marshal return
results; otherwise returns false.
/**
     * Returns true if this output stream is used to marshal return
     * results; otherwise returns false.
     */
    boolean isResultStream() {
        return resultStream;
    }

    
Saves a reference to the specified object in this stream's
DGCAckHandler.
/**
     * Saves a reference to the specified object in this stream's
     * DGCAckHandler.
     **/
    void saveObject(Object obj) {
        // should always be accessed from same thread
        if (dgcAckHandler == null) {
            dgcAckHandler = new DGCAckHandler(ackID);
        }
        dgcAckHandler.add(obj);
    }

    
Returns this stream's DGCAckHandler, or null if it doesn't have
one (saveObject was not invoked).  This method should only be
invoked after all objects have been written to the stream,
because future objects written may yet cause a DGCAckHandler to
be created (by invoking saveObject).
/**
     * Returns this stream's DGCAckHandler, or null if it doesn't have
     * one (saveObject was not invoked).  This method should only be
     * invoked after all objects have been written to the stream,
     * because future objects written may yet cause a DGCAckHandler to
     * be created (by invoking saveObject).
     **/
    DGCAckHandler getDGCAckHandler() {
        return dgcAckHandler;
    }

    void done() {
        if (dgcAckHandler != null) {
            dgcAckHandler.startTimer();
        }
    }
}