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package sun.rmi.transport;

import java.io.*;
import java.util.*;
import java.rmi.RemoteException;
import java.rmi.server.UID;
import sun.rmi.server.MarshalInputStream;
import sun.rmi.runtime.Log;

Special stream to keep track of refs being unmarshaled so that refs can be ref-counted locally.
Author:Ann Wollrath
/** * Special stream to keep track of refs being unmarshaled so that * refs can be ref-counted locally. * * @author Ann Wollrath */
class ConnectionInputStream extends MarshalInputStream {
indicates whether ack is required for DGC
/** indicates whether ack is required for DGC */
private boolean dgcAckNeeded = false;
Hashtable mapping Endpoints to lists of LiveRefs to register
/** Hashtable mapping Endpoints to lists of LiveRefs to register */
private Map<Endpoint, List<LiveRef>> incomingRefTable = new HashMap<>(5);
identifier for gc ack
/** identifier for gc ack*/
private UID ackID;
Constructs a marshal input stream using the underlying stream "in".
/** * Constructs a marshal input stream using the underlying * stream "in". */
ConnectionInputStream(InputStream in) throws IOException { super(in); } void readID() throws IOException { ackID = UID.read((DataInput) this); }
Save reference in order to send "dirty" call after all args/returns have been unmarshaled. Save in hashtable incomingRefTable. This table is keyed on endpoints, and holds objects of type IncomingRefTableEntry.
/** * Save reference in order to send "dirty" call after all args/returns * have been unmarshaled. Save in hashtable incomingRefTable. This * table is keyed on endpoints, and holds objects of type * IncomingRefTableEntry. */
void saveRef(LiveRef ref) { Endpoint ep = ref.getEndpoint(); // check whether endpoint is already in the hashtable List<LiveRef> refList = incomingRefTable.get(ep); if (refList == null) { refList = new ArrayList<LiveRef>(); incomingRefTable.put(ep, refList); } // add ref to list of refs for endpoint ep refList.add(ref); }
Discard the saved incoming refs so there is nothing to register when registerRefs is called.
/** * Discard the saved incoming refs so there is nothing to register * when {@code registerRefs} is called. */
void discardRefs() { incomingRefTable.clear(); }
Add references to DGC table (and possibly send dirty call). RegisterRefs now calls DGCClient.referenced on all refs with the same endpoint at once to achieve batching of calls to the DGC
/** * Add references to DGC table (and possibly send dirty call). * RegisterRefs now calls DGCClient.referenced on all * refs with the same endpoint at once to achieve batching of * calls to the DGC */
void registerRefs() throws IOException { if (!incomingRefTable.isEmpty()) { for (Map.Entry<Endpoint, List<LiveRef>> entry : incomingRefTable.entrySet()) { DGCClient.registerRefs(entry.getKey(), entry.getValue()); } } }
Indicate that an ack is required to the distributed collector.
/** * Indicate that an ack is required to the distributed * collector. */
void setAckNeeded() { dgcAckNeeded = true; }
Done with input stream for remote call. Send DGC ack if necessary. Allow sending of ack to fail without flagging an error.
/** * Done with input stream for remote call. Send DGC ack if necessary. * Allow sending of ack to fail without flagging an error. */
void done(Connection c) { /* * WARNING: The connection c may have already been freed. It * is only be safe to use c to obtain c's channel. */ if (dgcAckNeeded) { Connection conn = null; Channel ch = null; boolean reuse = true; DGCImpl.dgcLog.log(Log.VERBOSE, "send ack"); try { ch = c.getChannel(); conn = ch.newConnection(); DataOutputStream out = new DataOutputStream(conn.getOutputStream()); out.writeByte(TransportConstants.DGCAck); if (ackID == null) { ackID = new UID(); } ackID.write((DataOutput) out); conn.releaseOutputStream(); /* * Fix for 4221173: if this connection is on top of an * HttpSendSocket, the DGCAck won't actually get sent until a * read operation is attempted on the socket. Calling * available() is the most innocuous way of triggering the * write. */ conn.getInputStream().available(); conn.releaseInputStream(); } catch (RemoteException e) { reuse = false; } catch (IOException e) { reuse = false; } try { if (conn != null) ch.free(conn, reuse); } catch (RemoteException e){ // eat exception } } } }