/**
* This file is part of ObjectFabric (http://objectfabric.org).
*
* ObjectFabric is licensed under the Apache License, Version 2.0, the terms
* of which may be found at http://www.apache.org/licenses/LICENSE-2.0.html.
*
* Copyright ObjectFabric Inc.
*
* This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
* WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
package org.objectfabric;
import org.objectfabric.Actor.Message;
/**
* Network location.
*/
@SuppressWarnings("rawtypes")
public abstract class Remote extends Origin {
public enum Status {
DISCONNECTED, CONNECTING, WAITING_RETRY, SYNCHRONIZING, UP_TO_DATE
}
public static final String TCP = "tcp", SSL = "ssl", WS = "ws", WSS = "wss";
public static final String WS_PATH = "/websocket";
private static final long NO_RETRY = -1;
private final Address _address;
private final Run _run = new Run();
private int _actives;
private ConnectionAttempt _attempt;
private String _info;
private long _lastAttempt;
private volatile Connection _connection;
protected Remote(boolean cache, Address address) {
super(cache);
_address = address;
_run.onStarted();
}
final Address address() {
return _address;
}
final Connection connection() {
return _connection;
}
// TODO listener
public final Status status() {
if (_connection != null)
return InFlight.idle() ? Status.UP_TO_DATE : Status.SYNCHRONIZING;
if (_actives == 0 || _lastAttempt == NO_RETRY || !ClientURIHandler.isEnabled())
return Status.DISCONNECTED;
if (_attempt != null)
return Status.CONNECTING;
return Status.WAITING_RETRY;
}
public final String statusInfo() {
return _info;
}
//
@Override
View newView(URI uri) {
return new ClientView(this);
}
final void onOpen(final URI uri) {
_run.addAndRun(new Message() {
@Override
void run() {
invariants();
if (_connection != null)
_connection.postSubscribe(uri);
if (_actives++ == 0 && _lastAttempt != NO_RETRY)
retry();
invariants();
}
});
}
final void onClose(final URI uri) {
_run.addAndRun(new Message() {
@Override
void run() {
invariants();
// TODO grace period
if (--_actives == 0) {
if (_connection != null) {
_connection.requestClose(null);
_connection = null;
} else
closeAttempt();
}
invariants();
}
});
}
/*
*
*/
interface ConnectionAttempt {
void start();
void cancel();
}
abstract ConnectionAttempt createAttempt();
private final void closeAttempt() {
if (_attempt != null) {
_attempt.cancel();
_attempt = null;
}
}
//
final void retry() {
_run.addAndRun(new Message() {
@Override
void run() {
invariants();
ConnectionAttempt toStart = null;
closeAttempt();
if (_actives > 0) {
if (_connection == null) {
_attempt = toStart = createAttempt();
_lastAttempt = Platform.get().approxTimeMs();
if (!Debug.COMMUNICATIONS_DISABLE_TIMERS) {
Platform.get().schedule(new Runnable() {
@Override
public void run() {
onError(null, Strings.TIMEOUT, true);
}
}, 4000);
}
}
}
invariants();
if (toStart != null)
toStart.start();
}
});
}
final void onConnection(final Connection connection) {
if (Debug.ENABLED)
Debug.assertion(connection != null);
_run.addAndRun(new Message() {
@SuppressWarnings("null")
@Override
void run() {
invariants();
if (_attempt == null || _actives == 0)
connection.requestClose(null);
else {
_attempt = null;
_connection = connection;
if (!isCache()) {
for (final URI uri : uris().values()) {
uri.runIf(new Runnable() {
@Override
public void run() {
connection.postSubscribe(uri);
}
}, true);
}
}
}
invariants();
}
});
}
final void unsubscribe(final URI uri) {
_run.addAndRun(new Message() {
@Override
void run() {
if (_connection != null) {
uri.runIf(new Runnable() {
@Override
public void run() {
_connection.postUnsubscribe(uri);
}
}, false);
}
}
});
}
final void onError(final Connection connection, final String info, final boolean canRetry) {
if (Debug.ENABLED)
Debug.assertion(info != null);
_run.addAndRun(new Message() {
@Override
void run() {
invariants();
long now = 0, next = 0;
boolean ignore = true;
if (connection == null && _attempt != null) {
closeAttempt();
ignore = false;
}
if (connection != null && connection == _connection) {
connection.requestClose(null);
_connection = null;
ignore = false;
}
if (!ignore) {
if (!canRetry)
_lastAttempt = NO_RETRY;
if (_actives > 0 && _lastAttempt != NO_RETRY) {
now = Platform.get().approxTimeMs(); // try every rand(8s)
next = _lastAttempt + Platform.get().randomInt(8192);
}
_info = info;
}
if (next == 0) {
if (connection != null)
Log.write(this + ": " + info);
} else {
if (!Debug.COMMUNICATIONS_DISABLE_TIMERS) {
int delay = next <= now ? 0 : (int) (next - now);
Platform.get().schedule(new Runnable() {
@Override
public void run() {
retry();
}
}, delay);
}
}
invariants();
}
});
}
@SuppressWarnings("serial")
private final class Run extends Actor implements Runnable {
@Override
protected void enqueue() {
Platform.get().execute(this);
}
@Override
public void run() {
if (Debug.ENABLED)
ThreadAssert.resume(this, false);
onRunStarting();
runMessages(false);
if (Debug.ENABLED)
ThreadAssert.suspend(this);
onRunEnded(false);
}
}
//
abstract Headers headers();
//
@Override
void sha1(SHA1Digest sha1) {
sha1.update(_address.Scheme);
sha1.update(_address.Host);
sha1.update((byte) (_address.Port >> 8));
sha1.update((byte) (_address.Port >> 0));
}
@Override
public String toString() {
String s = "";
if (Debug.ENABLED)
s += Platform.get().defaultToString(this) + "-";
return s + _address.toString();
}
// Debug
private final void invariants() {
if (Debug.ENABLED) {
if (_actives == 0)
Debug.assertion(_attempt == null && _connection == null);
else
Debug.assertion(_attempt == null || _connection == null);
}
}
}