protected void getState(Address target, long timeout, Callable<Boolean> flushInvoker)
throws Exception {
checkClosedOrNotConnected();
if (!state_transfer_supported)
throw new IllegalStateException(
"fetching state will fail as state transfer is not supported. "
+ "Add one of the state transfer protocols to your configuration");
if (target == null) target = determineCoordinator();
if (target != null && local_addr != null && target.equals(local_addr)) {
log.trace(
local_addr
+ ": cannot get state from myself ("
+ target
+ "): probably the first member");
return;
}
boolean initiateFlush = flushSupported() && flushInvoker != null;
if (initiateFlush) {
boolean successfulFlush = false;
try {
successfulFlush = flushInvoker.call();
} catch (Throwable e) {
successfulFlush = false; // http://jira.jboss.com/jira/browse/JGRP-759
}
if (!successfulFlush)
throw new IllegalStateException(
"Node " + local_addr + " could not flush the cluster for state retrieval");
}
state_promise.reset();
StateTransferInfo state_info = new StateTransferInfo(target, timeout);
long start = System.currentTimeMillis();
down(new Event(Event.GET_STATE, state_info));
StateTransferResult result = state_promise.getResult(state_info.timeout);
if (initiateFlush) stopFlush();
if (result == null)
throw new StateTransferException(
"timeout during state transfer (" + (System.currentTimeMillis() - start) + "ms)");
if (result.hasException())
throw new StateTransferException("state transfer failed", result.getException());
}
/**
* Callback method <br>
* Called by the ProtocolStack when a message is received.
*
* @param evt the event carrying the message from the protocol stack
*/
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
if (stats) {
received_msgs++;
received_bytes += msg.getLength();
}
// discard local messages (sent by myself to me)
if (discard_own_messages
&& local_addr != null
&& msg.getSrc() != null
&& local_addr.equals(msg.getSrc())) return null;
break;
case Event.VIEW_CHANGE:
View tmp = (View) evt.getArg();
if (tmp instanceof MergeView) my_view = new View(tmp.getViewId(), tmp.getMembers());
else my_view = tmp;
// Bela&Vladimir Oct 27th,2006 (JGroups 2.4): we need to set connected=true because a client
// can
// call channel.getView() in viewAccepted() callback invoked on this thread (see
// Event.VIEW_CHANGE handling below)
// not good: we are only connected when we returned from connect() - bela June 22 2007
// Changed: when a channel gets a view of which it is a member then it should be
// connected even if connect() hasn't returned yet ! (bela Noc 2010)
if (state != State.CONNECTED) state = State.CONNECTED;
break;
case Event.CONFIG:
Map<String, Object> cfg = (Map<String, Object>) evt.getArg();
if (cfg != null) {
if (cfg.containsKey("state_transfer")) {
state_transfer_supported = (Boolean) cfg.get("state_transfer");
}
if (cfg.containsKey("flush_supported")) {
flush_supported = (Boolean) cfg.get("flush_supported");
}
}
break;
case Event.GET_STATE_OK:
StateTransferResult result = (StateTransferResult) evt.getArg();
if (up_handler != null) {
try {
Object retval = up_handler.up(evt);
state_promise.setResult(new StateTransferResult());
return retval;
} catch (Throwable t) {
state_promise.setResult(new StateTransferResult(t));
}
}
if (receiver != null) {
try {
if (result.hasBuffer()) {
byte[] tmp_state = result.getBuffer();
ByteArrayInputStream input = new ByteArrayInputStream(tmp_state);
receiver.setState(input);
}
state_promise.setResult(result);
} catch (Throwable t) {
state_promise.setResult(new StateTransferResult(t));
}
}
break;
case Event.STATE_TRANSFER_INPUTSTREAM_CLOSED:
state_promise.setResult((StateTransferResult) evt.getArg());
break;
case Event.STATE_TRANSFER_INPUTSTREAM:
// Oct 13,2006 moved to down() when Event.STATE_TRANSFER_INPUTSTREAM_CLOSED is received
// state_promise.setResult(is != null? Boolean.TRUE : Boolean.FALSE);
if (up_handler != null) return up_handler.up(evt);
InputStream is = (InputStream) evt.getArg();
if (is != null && receiver != null) {
try {
receiver.setState(is);
} catch (Throwable t) {
throw new RuntimeException("failed calling setState() in state requester", t);
}
}
break;
case Event.STATE_TRANSFER_OUTPUTSTREAM:
if (receiver != null && evt.getArg() != null) {
try {
receiver.getState((OutputStream) evt.getArg());
} catch (Exception e) {
throw new RuntimeException("failed calling getState() in state provider", e);
}
}
break;
case Event.GET_LOCAL_ADDRESS:
return local_addr;
default:
break;
}
// If UpHandler is installed, pass all events to it and return (UpHandler is e.g. a building
// block)
if (up_handler != null) return up_handler.up(evt);
if (receiver != null) return invokeCallback(evt.getType(), evt.getArg());
return null;
}
protected Object handleUpEvent(Event evt) throws Exception {
switch (evt.getType()) {
case Event.MSG:
if (msg_listener != null) msg_listener.receive((Message) evt.getArg());
break;
case Event.GET_APPLSTATE: // reply with GET_APPLSTATE_OK
byte[] tmp_state = null;
if (msg_listener != null) {
ByteArrayOutputStream output = new ByteArrayOutputStream(1024);
msg_listener.getState(output);
tmp_state = output.toByteArray();
}
return new StateTransferInfo(null, 0L, tmp_state);
case Event.GET_STATE_OK:
if (msg_listener != null) {
StateTransferResult result = (StateTransferResult) evt.getArg();
if (result.hasBuffer()) {
ByteArrayInputStream input = new ByteArrayInputStream(result.getBuffer());
msg_listener.setState(input);
}
}
break;
case Event.STATE_TRANSFER_OUTPUTSTREAM:
OutputStream os = (OutputStream) evt.getArg();
if (msg_listener != null && os != null) {
msg_listener.getState(os);
}
break;
case Event.STATE_TRANSFER_INPUTSTREAM:
InputStream is = (InputStream) evt.getArg();
if (msg_listener != null && is != null) msg_listener.setState(is);
break;
case Event.VIEW_CHANGE:
View v = (View) evt.getArg();
List<Address> new_mbrs = v.getMembers();
setMembers(new_mbrs);
if (membership_listener != null) membership_listener.viewAccepted(v);
break;
case Event.SET_LOCAL_ADDRESS:
if (log.isTraceEnabled())
log.trace("setting local_addr (" + local_addr + ") to " + evt.getArg());
local_addr = (Address) evt.getArg();
break;
case Event.SUSPECT:
if (membership_listener != null) membership_listener.suspect((Address) evt.getArg());
break;
case Event.BLOCK:
if (membership_listener != null) membership_listener.block();
break;
case Event.UNBLOCK:
if (membership_listener != null) membership_listener.unblock();
break;
}
return null;
}