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Refactored various websockets to event bus from old BlockNotifier/StatusNotifier

split-DB
catbref 4 years ago
parent
0b5e5832c4
commit
1cd4bbc078
6 changed files with 257 additions and 253 deletions
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  1. 74
      src/main/java/org/qortal/api/websocket/AdminStatusWebSocket.java
  2. 36
      src/main/java/org/qortal/api/websocket/BlocksWebSocket.java
  3. 247
      src/main/java/org/qortal/api/websocket/TradeOffersWebSocket.java
  4. 61
      src/main/java/org/qortal/controller/BlockNotifier.java
  5. 24
      src/main/java/org/qortal/controller/Controller.java
  6. 56
      src/main/java/org/qortal/controller/StatusNotifier.java

74
src/main/java/org/qortal/api/websocket/AdminStatusWebSocket.java
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@ -13,59 +13,87 @@ import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
import org.eclipse.jetty.websocket.api.annotations.WebSocket;
import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
import org.qortal.api.model.NodeStatus;
import org.qortal.controller.StatusNotifier;
import org.qortal.repository.DataException;
import org.qortal.repository.Repository;
import org.qortal.repository.RepositoryManager;
import org.qortal.controller.Controller;
import org.qortal.event.Event;
import org.qortal.event.EventBus;
import org.qortal.event.Listener;
@WebSocket
@SuppressWarnings("serial")
public class AdminStatusWebSocket extends ApiWebSocket {
public class AdminStatusWebSocket extends ApiWebSocket implements Listener {
private static final AtomicReference<String> previousOutput = new AtomicReference<>(null);
@Override
public void configure(WebSocketServletFactory factory) {
factory.register(AdminStatusWebSocket.class);
try {
previousOutput.set(buildStatusString());
} catch (IOException e) {
// How to fail properly?
return;
}
EventBus.INSTANCE.addListener(this::listen);
}
@Override
public void listen(Event event) {
if (!(event instanceof Controller.StatusChangeEvent))
return;
String newOutput;
try {
newOutput = buildStatusString();
} catch (IOException e) {
// Ignore this time?
return;
}
if (previousOutput.getAndUpdate(currentValue -> newOutput).equals(newOutput))
// Output hasn't changed, so don't send anything
return;
for (Session session : getSessions())
this.sendStatus(session, newOutput);
}
@OnWebSocketConnect
@Override
public void onWebSocketConnect(Session session) {
AtomicReference<String> previousOutput = new AtomicReference<>(null);
StatusNotifier.Listener listener = timestamp -> onNotify(session, previousOutput);
StatusNotifier.getInstance().register(session, listener);
this.sendStatus(session, previousOutput.get());
this.onNotify(session, previousOutput);
super.onWebSocketConnect(session);
}
@OnWebSocketClose
@Override
public void onWebSocketClose(Session session, int statusCode, String reason) {
StatusNotifier.getInstance().deregister(session);
super.onWebSocketClose(session, statusCode, reason);
}
@OnWebSocketError
public void onWebSocketError(Session session, Throwable throwable) {
/* We ignore errors for now, but method here to silence log spam */
}
@OnWebSocketMessage
public void onWebSocketMessage(Session session, String message) {
/* ignored */
}
private void onNotify(Session session,AtomicReference<String> previousOutput) {
try (final Repository repository = RepositoryManager.getRepository()) {
private static String buildStatusString() throws IOException {
NodeStatus nodeStatus = new NodeStatus();
StringWriter stringWriter = new StringWriter();
marshall(stringWriter, nodeStatus);
return stringWriter.toString();
}
// Only output if something has changed
String output = stringWriter.toString();
if (output.equals(previousOutput.get()))
return;
previousOutput.set(output);
session.getRemote().sendStringByFuture(output);
} catch (DataException | IOException | WebSocketException e) {
private void sendStatus(Session session, String status) {
try {
session.getRemote().sendStringByFuture(status);
} catch (WebSocketException e) {
// No output this time?
}
}

36
src/main/java/org/qortal/api/websocket/BlocksWebSocket.java
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@ -14,7 +14,11 @@ import org.eclipse.jetty.websocket.api.annotations.WebSocket;
import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
import org.qortal.api.ApiError;
import org.qortal.api.model.BlockInfo;
import org.qortal.controller.BlockNotifier;
import org.qortal.controller.Controller;
import org.qortal.data.block.BlockData;
import org.qortal.event.Event;
import org.qortal.event.EventBus;
import org.qortal.event.Listener;
import org.qortal.repository.DataException;
import org.qortal.repository.Repository;
import org.qortal.repository.RepositoryManager;
@ -22,26 +26,42 @@ import org.qortal.utils.Base58;
@WebSocket
@SuppressWarnings("serial")
public class BlocksWebSocket extends ApiWebSocket {
public class BlocksWebSocket extends ApiWebSocket implements Listener {
@Override
public void configure(WebSocketServletFactory factory) {
factory.register(BlocksWebSocket.class);
EventBus.INSTANCE.addListener(this::listen);
}
@Override
public void listen(Event event) {
if (!(event instanceof Controller.NewBlockEvent))
return;
BlockData blockData = ((Controller.NewBlockEvent) event).getBlockData();
BlockInfo blockInfo = new BlockInfo(blockData);
for (Session session : getSessions())
sendBlockInfo(session, blockInfo);
}
@OnWebSocketConnect
@Override
public void onWebSocketConnect(Session session) {
BlockNotifier.Listener listener = blockInfo -> onNotify(session, blockInfo);
BlockNotifier.getInstance().register(session, listener);
super.onWebSocketConnect(session);
}
@OnWebSocketClose
@Override
public void onWebSocketClose(Session session, int statusCode, String reason) {
BlockNotifier.getInstance().deregister(session);
super.onWebSocketClose(session, statusCode, reason);
}
@OnWebSocketError
public void onWebSocketError(Session session, Throwable throwable) {
/* We ignore errors for now, but method here to silence log spam */
}
@OnWebSocketMessage
@ -71,7 +91,7 @@ public class BlocksWebSocket extends ApiWebSocket {
return;
}
onNotify(session, blockInfos.get(0));
sendBlockInfo(session, blockInfos.get(0));
} catch (DataException e) {
sendError(session, ApiError.REPOSITORY_ISSUE);
}
@ -100,13 +120,13 @@ public class BlocksWebSocket extends ApiWebSocket {
return;
}
onNotify(session, blockInfos.get(0));
sendBlockInfo(session, blockInfos.get(0));
} catch (DataException e) {
sendError(session, ApiError.REPOSITORY_ISSUE);
}
}
private void onNotify(Session session, BlockInfo blockInfo) {
private void sendBlockInfo(Session session, BlockInfo blockInfo) {
StringWriter stringWriter = new StringWriter();
try {

247
src/main/java/org/qortal/api/websocket/TradeOffersWebSocket.java
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@ -6,6 +6,7 @@ import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Predicate;
import java.util.stream.Collectors;
import org.eclipse.jetty.websocket.api.Session;
@ -14,12 +15,15 @@ import org.eclipse.jetty.websocket.api.annotations.OnWebSocketConnect;
import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
import org.eclipse.jetty.websocket.api.annotations.WebSocket;
import org.eclipse.jetty.websocket.servlet.WebSocketServletFactory;
import org.qortal.api.model.BlockInfo;
import org.qortal.api.model.CrossChainOfferSummary;
import org.qortal.controller.BlockNotifier;
import org.qortal.controller.Controller;
import org.qortal.crosschain.BTCACCT;
import org.qortal.data.at.ATStateData;
import org.qortal.data.block.BlockData;
import org.qortal.data.crosschain.CrossChainTradeData;
import org.qortal.event.Event;
import org.qortal.event.EventBus;
import org.qortal.event.Listener;
import org.qortal.repository.DataException;
import org.qortal.repository.Repository;
import org.qortal.repository.RepositoryManager;
@ -27,104 +31,130 @@ import org.qortal.utils.NTP;
@WebSocket
@SuppressWarnings("serial")
public class TradeOffersWebSocket extends ApiWebSocket {
public class TradeOffersWebSocket extends ApiWebSocket implements Listener {
@Override
public void configure(WebSocketServletFactory factory) {
factory.register(TradeOffersWebSocket.class);
}
private static final Map<String, BTCACCT.Mode> previousAtModes = new HashMap<>();
@OnWebSocketConnect
public void onWebSocketConnect(Session session) {
Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
// OFFERING
private static final List<CrossChainOfferSummary> currentSummaries = new ArrayList<>();
// REDEEMED/REFUNDED/CANCELLED
private static final List<CrossChainOfferSummary> historicSummaries = new ArrayList<>();
final boolean includeHistoric = queryParams.get("includeHistoric") != null;
final Map<String, BTCACCT.Mode> previousAtModes = new HashMap<>();
List<CrossChainOfferSummary> crossChainOfferSummaries;
private static final Predicate<CrossChainOfferSummary> isCurrent = offerSummary
-> offerSummary.getMode() == BTCACCT.Mode.OFFERING;
try (final Repository repository = RepositoryManager.getRepository()) {
List<ATStateData> initialAtStates;
private static final Predicate<CrossChainOfferSummary> isHistoric = offerSummary
-> offerSummary.getMode() == BTCACCT.Mode.REDEEMED
|| offerSummary.getMode() == BTCACCT.Mode.REFUNDED
|| offerSummary.getMode() == BTCACCT.Mode.CANCELLED;
// We want ALL OFFERING trades
Boolean isFinished = Boolean.FALSE;
Integer dataByteOffset = BTCACCT.MODE_BYTE_OFFSET;
Long expectedValue = (long) BTCACCT.Mode.OFFERING.value;
Integer minimumFinalHeight = null;
initialAtStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
isFinished, dataByteOffset, expectedValue, minimumFinalHeight,
null, null, null);
@Override
public void configure(WebSocketServletFactory factory) {
factory.register(TradeOffersWebSocket.class);
try (final Repository repository = RepositoryManager.getRepository()) {
populateCurrentSummaries(repository);
if (initialAtStates == null) {
session.close(4001, "repository issue fetching OFFERING trades");
populateHistoricSummaries(repository);
} catch (DataException e) {
// How to fail properly?
return;
}
// Save initial AT modes
previousAtModes.putAll(initialAtStates.stream().collect(Collectors.toMap(ATStateData::getATAddress, atState -> BTCACCT.Mode.OFFERING)));
EventBus.INSTANCE.addListener(this::listen);
}
// Convert to offer summaries
crossChainOfferSummaries = produceSummaries(repository, initialAtStates, null);
@Override
public void listen(Event event) {
if (!(event instanceof Controller.NewBlockEvent))
return;
if (includeHistoric) {
// We also want REDEEMED/REFUNDED/CANCELLED trades over the last 24 hours
long timestamp = NTP.getTime() - 24 * 60 * 60 * 1000L;
minimumFinalHeight = repository.getBlockRepository().getHeightFromTimestamp(timestamp);
BlockData blockData = ((Controller.NewBlockEvent) event).getBlockData();
if (minimumFinalHeight != 0) {
isFinished = Boolean.TRUE;
dataByteOffset = null;
expectedValue = null;
++minimumFinalHeight; // because height is just *before* timestamp
// Process any new info
List<CrossChainOfferSummary> crossChainOfferSummaries;
List<ATStateData> historicAtStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
try (final Repository repository = RepositoryManager.getRepository()) {
// Find any new trade ATs since this block
final Boolean isFinished = null;
final Integer dataByteOffset = null;
final Long expectedValue = null;
final Integer minimumFinalHeight = blockData.getHeight();
List<ATStateData> atStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
isFinished, dataByteOffset, expectedValue, minimumFinalHeight,
null, null, null);
if (historicAtStates == null) {
session.close(4002, "repository issue fetching historic trades");
if (atStates == null)
return;
crossChainOfferSummaries = produceSummaries(repository, atStates, blockData.getTimestamp());
} catch (DataException e) {
// No output this time
return;
}
for (ATStateData historicAtState : historicAtStates) {
CrossChainOfferSummary historicOfferSummary = produceSummary(repository, historicAtState, null);
synchronized (previousAtModes) {
// Remove any entries unchanged from last time
crossChainOfferSummaries.removeIf(offerSummary -> previousAtModes.get(offerSummary.getQortalAtAddress()) == offerSummary.getMode());
switch (historicOfferSummary.getMode()) {
case REDEEMED:
case REFUNDED:
case CANCELLED:
break;
// Don't send anything if no results
if (crossChainOfferSummaries.isEmpty())
return;
default:
continue;
// Update
previousAtModes.putAll(crossChainOfferSummaries.stream().collect(Collectors.toMap(CrossChainOfferSummary::getQortalAtAddress, CrossChainOfferSummary::getMode)));
synchronized (currentSummaries) {
// Add any OFFERING to 'current'
currentSummaries.addAll(crossChainOfferSummaries.stream().filter(isCurrent).collect(Collectors.toList()));
}
// Add summary to initial burst
crossChainOfferSummaries.add(historicOfferSummary);
final long tooOldTimestamp = NTP.getTime() - 24 * 60 * 60 * 1000L;
synchronized (historicSummaries) {
// Add any REDEEMED/REFUNDED/CANCELLED
historicSummaries.addAll(crossChainOfferSummaries.stream().filter(isHistoric).collect(Collectors.toList()));
// Save initial AT mode
previousAtModes.put(historicAtState.getATAddress(), historicOfferSummary.getMode());
// But also remove any that are over 24 hours old
historicSummaries.removeIf(offerSummary -> offerSummary.getTimestamp() < tooOldTimestamp);
}
}
// Notify sessions
for (Session session : getSessions())
sendOfferSummaries(session, crossChainOfferSummaries);
}
} catch (DataException e) {
session.close(4003, "generic repository issue");
return;
@OnWebSocketConnect
@Override
public void onWebSocketConnect(Session session) {
Map<String, List<String>> queryParams = session.getUpgradeRequest().getParameterMap();
final boolean includeHistoric = queryParams.get("includeHistoric") != null;
List<CrossChainOfferSummary> crossChainOfferSummaries;
synchronized (currentSummaries) {
crossChainOfferSummaries = new ArrayList<>(currentSummaries);
}
if (includeHistoric)
synchronized (historicSummaries) {
crossChainOfferSummaries.addAll(historicSummaries);
}
if (!sendOfferSummaries(session, crossChainOfferSummaries)) {
session.close(4004, "websocket issue");
session.close(4002, "websocket issue");
return;
}
BlockNotifier.Listener listener = blockInfo -> onNotify(session, blockInfo, previousAtModes);
BlockNotifier.getInstance().register(session, listener);
super.onWebSocketConnect(session);
}
@OnWebSocketClose
@Override
public void onWebSocketClose(Session session, int statusCode, String reason) {
BlockNotifier.getInstance().deregister(session);
super.onWebSocketClose(session, statusCode, reason);
}
@OnWebSocketMessage
@ -132,58 +162,81 @@ public class TradeOffersWebSocket extends ApiWebSocket {
/* ignored */
}
private void onNotify(Session session, BlockInfo blockInfo, final Map<String, BTCACCT.Mode> previousAtModes) {
List<CrossChainOfferSummary> crossChainOfferSummaries = null;
private boolean sendOfferSummaries(Session session, List<CrossChainOfferSummary> crossChainOfferSummaries) {
try {
StringWriter stringWriter = new StringWriter();
marshall(stringWriter, crossChainOfferSummaries);
try (final Repository repository = RepositoryManager.getRepository()) {
// Find any new trade ATs since this block
final Boolean isFinished = null;
final Integer dataByteOffset = null;
final Long expectedValue = null;
final Integer minimumFinalHeight = blockInfo.getHeight();
String output = stringWriter.toString();
session.getRemote().sendStringByFuture(output);
} catch (IOException e) {
// No output this time?
return false;
}
List<ATStateData> atStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
return true;
}
private static void populateCurrentSummaries(Repository repository) throws DataException {
// We want ALL OFFERING trades
Boolean isFinished = Boolean.FALSE;
Integer dataByteOffset = BTCACCT.MODE_BYTE_OFFSET;
Long expectedValue = (long) BTCACCT.Mode.OFFERING.value;
Integer minimumFinalHeight = null;
List<ATStateData> initialAtStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
isFinished, dataByteOffset, expectedValue, minimumFinalHeight,
null, null, null);
if (atStates == null)
return;
if (initialAtStates == null)
throw new DataException("Couldn't fetch current trades from repository");
crossChainOfferSummaries = produceSummaries(repository, atStates, blockInfo.getTimestamp());
} catch (DataException e) {
// No output this time
// Save initial AT modes
previousAtModes.putAll(initialAtStates.stream().collect(Collectors.toMap(ATStateData::getATAddress, atState -> BTCACCT.Mode.OFFERING)));
// Convert to offer summaries
currentSummaries.addAll(produceSummaries(repository, initialAtStates, null));
}
synchronized (previousAtModes) { //NOSONAR squid:S2445 suppressed because previousAtModes is final and curried in lambda
// Remove any entries unchanged from last time
crossChainOfferSummaries.removeIf(offerSummary -> previousAtModes.get(offerSummary.getQortalAtAddress()) == offerSummary.getMode());
private static void populateHistoricSummaries(Repository repository) throws DataException {
// We want REDEEMED/REFUNDED/CANCELLED trades over the last 24 hours
long timestamp = System.currentTimeMillis() - 24 * 60 * 60 * 1000L;
int minimumFinalHeight = repository.getBlockRepository().getHeightFromTimestamp(timestamp);
// Don't send anything if no results
if (crossChainOfferSummaries.isEmpty())
return;
if (minimumFinalHeight == 0)
throw new DataException("Couldn't fetch block timestamp from repository");
final boolean wasSent = sendOfferSummaries(session, crossChainOfferSummaries);
Boolean isFinished = Boolean.TRUE;
Integer dataByteOffset = null;
Long expectedValue = null;
++minimumFinalHeight; // because height is just *before* timestamp
if (!wasSent)
return;
List<ATStateData> historicAtStates = repository.getATRepository().getMatchingFinalATStates(BTCACCT.CODE_BYTES_HASH,
isFinished, dataByteOffset, expectedValue, minimumFinalHeight,
null, null, null);
previousAtModes.putAll(crossChainOfferSummaries.stream().collect(Collectors.toMap(CrossChainOfferSummary::getQortalAtAddress, CrossChainOfferSummary::getMode)));
}
}
if (historicAtStates == null)
throw new DataException("Couldn't fetch historic trades from repository");
private boolean sendOfferSummaries(Session session, List<CrossChainOfferSummary> crossChainOfferSummaries) {
try {
StringWriter stringWriter = new StringWriter();
marshall(stringWriter, crossChainOfferSummaries);
for (ATStateData historicAtState : historicAtStates) {
CrossChainOfferSummary historicOfferSummary = produceSummary(repository, historicAtState, null);
String output = stringWriter.toString();
session.getRemote().sendStringByFuture(output);
} catch (IOException e) {
// No output this time?
return false;
switch (historicOfferSummary.getMode()) {
case REDEEMED:
case REFUNDED:
case CANCELLED:
break;
default:
continue;
}
return true;
// Add summary to initial burst
historicSummaries.add(historicOfferSummary);
// Save initial AT mode
previousAtModes.put(historicAtState.getATAddress(), historicOfferSummary.getMode());
}
}
private static CrossChainOfferSummary produceSummary(Repository repository, ATStateData atState, Long timestamp) throws DataException {

61
src/main/java/org/qortal/controller/BlockNotifier.java
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@ -1,61 +0,0 @@
package org.qortal.controller;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.jetty.websocket.api.Session;
import org.qortal.api.model.BlockInfo;
import org.qortal.data.block.BlockData;
public class BlockNotifier {
private static BlockNotifier instance;
@FunctionalInterface
public interface Listener {
void notify(BlockInfo blockInfo);
}
private Map<Session, Listener> listenersBySession = new HashMap<>();
private BlockNotifier() {
}
public static synchronized BlockNotifier getInstance() {
if (instance == null)
instance = new BlockNotifier();
return instance;
}
public void register(Session session, Listener listener) {
synchronized (this.listenersBySession) {
this.listenersBySession.put(session, listener);
}
}
public void deregister(Session session) {
synchronized (this.listenersBySession) {
this.listenersBySession.remove(session);
}
}
public void onNewBlock(BlockData blockData) {
// Convert BlockData to BlockInfo
BlockInfo blockInfo = new BlockInfo(blockData);
for (Listener listener : getAllListeners())
listener.notify(blockInfo);
}
private Collection<Listener> getAllListeners() {
// Make a copy of listeners to both avoid concurrent modification
// and reduce synchronization time
synchronized (this.listenersBySession) {
return new ArrayList<>(this.listenersBySession.values());
}
}
}

24
src/main/java/org/qortal/controller/Controller.java
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@ -50,6 +50,8 @@ import org.qortal.data.network.PeerData;
import org.qortal.data.transaction.ArbitraryTransactionData;
import org.qortal.data.transaction.TransactionData;
import org.qortal.data.transaction.ArbitraryTransactionData.DataType;
import org.qortal.event.Event;
import org.qortal.event.EventBus;
import org.qortal.data.transaction.ChatTransactionData;
import org.qortal.globalization.Translator;
import org.qortal.gui.Gui;
@ -629,6 +631,11 @@ public class Controller extends Thread {
}
}
public static class StatusChangeEvent implements Event {
public StatusChangeEvent() {
}
}
private void updateSysTray() {
if (NTP.getTime() == null) {
SysTray.getInstance().setToolTipText(Translator.INSTANCE.translate("SysTray", "SYNCHRONIZING_CLOCK"));
@ -656,7 +663,7 @@ public class Controller extends Thread {
SysTray.getInstance().setToolTipText(tooltip);
this.callbackExecutor.execute(() -> {
StatusNotifier.getInstance().onStatusChange(NTP.getTime());
EventBus.INSTANCE.notify(new StatusChangeEvent());
});
}
@ -783,6 +790,18 @@ public class Controller extends Thread {
requestSysTrayUpdate = true;
}
public static class NewBlockEvent implements Event {
private final BlockData blockData;
public NewBlockEvent(BlockData blockData) {
this.blockData = blockData;
}
public BlockData getBlockData() {
return this.blockData;
}
}
public void onNewBlock(BlockData latestBlockData) {
this.setChainTip(latestBlockData);
requestSysTrayUpdate = true;
@ -792,7 +811,8 @@ public class Controller extends Thread {
Network network = Network.getInstance();
network.broadcast(peer -> network.buildHeightMessage(peer, latestBlockData));
BlockNotifier.getInstance().onNewBlock(latestBlockData);
// Notify listeners of new block
EventBus.INSTANCE.notify(new NewBlockEvent(latestBlockData));
if (this.notifyGroupMembershipChange) {
this.notifyGroupMembershipChange = false;

56
src/main/java/org/qortal/controller/StatusNotifier.java
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@ -1,56 +0,0 @@
package org.qortal.controller;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.jetty.websocket.api.Session;
public class StatusNotifier {
private static StatusNotifier instance;
@FunctionalInterface
public interface Listener {
void notify(long timestamp);
}
private Map<Session, Listener> listenersBySession = new HashMap<>();
private StatusNotifier() {
}
public static synchronized StatusNotifier getInstance() {
if (instance == null)
instance = new StatusNotifier();
return instance;
}
public void register(Session session, Listener listener) {
synchronized (this.listenersBySession) {
this.listenersBySession.put(session, listener);
}
}
public void deregister(Session session) {
synchronized (this.listenersBySession) {
this.listenersBySession.remove(session);
}
}
public void onStatusChange(long now) {
for (Listener listener : getAllListeners())
listener.notify(now);
}
private Collection<Listener> getAllListeners() {
// Make a copy of listeners to both avoid concurrent modification
// and reduce synchronization time
synchronized (this.listenersBySession) {
return new ArrayList<>(this.listenersBySession.values());
}
}
}
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