优化 EventBus (#4565)

HMCL/src/main/java/org/jackhuang/hmcl/ui/construct/TaskExecutorDialogPane.java

@@ -40,6 +40,7 @@ import static org.jackhuang.hmcl.util.i18n.I18n.i18n;
 public class TaskExecutorDialogPane extends BorderPane {
     private TaskExecutor executor;
     private TaskCancellationAction onCancel;
+    @SuppressWarnings({"unused", "FieldCanBeLocal"})
     private final Consumer<FetchTask.SpeedEvent> speedEventHandler;
 
     private final Label lblTitle;
@@ -84,7 +85,7 @@ public class TaskExecutorDialogPane extends BorderPane {
             }
         });
 
-        speedEventHandler = speedEvent -> {
+        speedEventHandler = FetchTask.SPEED_EVENT.registerWeak(speedEvent -> {
             String unit = "B/s";
             double speed = speedEvent.getSpeed();
             if (speed > 1024) {
@@ -95,11 +96,10 @@ public class TaskExecutorDialogPane extends BorderPane {
                 speed /= 1024;
                 unit = "MiB/s";
             }
-            double finalSpeed = speed;
-            String finalUnit = unit;
-            Platform.runLater(() -> lblProgress.setText(String.format("%.1f %s", finalSpeed, finalUnit)));
-        };
-        FileDownloadTask.speedEvent.channel(FetchTask.SpeedEvent.class).registerWeak(speedEventHandler);
+
+            String message = String.format("%.1f %s", speed, unit);
+            Platform.runLater(() -> lblProgress.setText(message));
+        });
 
         onEscPressed(this, btnCancel::fire);
     }

HMCLCore/src/main/java/org/jackhuang/hmcl/event/EventBus.java

@@ -17,29 +17,32 @@
  */
 package org.jackhuang.hmcl.event;
 
-import java.util.concurrent.ConcurrentHashMap;
+import org.jetbrains.annotations.NotNull;
 
 import static org.jackhuang.hmcl.util.logging.Logger.LOG;
 
-/**
- *
- * @author huangyuhui
- */
-public final class EventBus {
+/// @author huangyuhui
+public final class EventBus extends ClassValue<EventManager<?>> {
 
-    private final ConcurrentHashMap<Class<?>, EventManager<?>> events = new ConcurrentHashMap<>();
+    public static final EventBus EVENT_BUS = new EventBus();
+
+    private EventBus() {
+    }
+
+    @Override
+    protected EventManager<?> computeValue(@NotNull Class<?> type) {
+        return new EventManager<>();
+    }
 
     @SuppressWarnings("unchecked")
     public <T extends Event> EventManager<T> channel(Class<T> clazz) {
-        return (EventManager<T>) events.computeIfAbsent(clazz, ignored -> new EventManager<>());
+        return (EventManager<T>) get(clazz);
     }
 
     @SuppressWarnings("unchecked")
     public Event.Result fireEvent(Event obj) {
         LOG.info(obj + " gets fired");
 
-        return channel((Class<Event>) obj.getClass()).fireEvent(obj);
+        return ((EventManager<Event>) get(obj.getClass())).fireEvent(obj);
     }
-
-    public static final EventBus EVENT_BUS = new EventBus();
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/event/EventManager.java

@@ -18,6 +18,7 @@
 package org.jackhuang.hmcl.event;
 
 import org.jackhuang.hmcl.util.SimpleMultimap;
+import org.jetbrains.annotations.Contract;
 
 import java.lang.ref.WeakReference;
 import java.util.EnumMap;
@@ -25,21 +26,20 @@ import java.util.concurrent.CopyOnWriteArraySet;
 import java.util.concurrent.locks.ReentrantLock;
 import java.util.function.Consumer;
 
-/**
- *
- * @author huangyuhui
- */
+/// @author huangyuhui
 public final class EventManager<T extends Event> {
 
     private final ReentrantLock lock = new ReentrantLock();
     private final SimpleMultimap<EventPriority, Consumer<T>, CopyOnWriteArraySet<Consumer<T>>> handlers
             = new SimpleMultimap<>(() -> new EnumMap<>(EventPriority.class), CopyOnWriteArraySet::new);
 
+    @Contract("_ -> param1")
     public Consumer<T> registerWeak(Consumer<T> consumer) {
         register(new WeakListener(consumer));
         return consumer;
     }
 
+    @Contract("_, _ -> param1")
     public Consumer<T> registerWeak(Consumer<T> consumer, EventPriority priority) {
         register(new WeakListener(consumer), priority);
         return consumer;

HMCLCore/src/main/java/org/jackhuang/hmcl/event/FailedEvent.java

@@ -1,47 +0,0 @@
-/*
- * Hello Minecraft! Launcher
- * Copyright (C) 2020  huangyuhui <huanghongxun2008@126.com> and contributors
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <https://www.gnu.org/licenses/>.
- */
-package org.jackhuang.hmcl.event;
-
-/**
- *
- * @author huang
- */
-public class FailedEvent<T> extends Event {
-
-    private final int failedTime;
-    private T newResult;
-
-    public FailedEvent(Object source, int failedTime, T newResult) {
-        super(source);
-        this.failedTime = failedTime;
-        this.newResult = newResult;
-    }
-
-    public int getFailedTime() {
-        return failedTime;
-    }
-
-    public T getNewResult() {
-        return newResult;
-    }
-
-    public void setNewResult(T newResult) {
-        this.newResult = newResult;
-    }
-
-}

HMCLCore/src/main/java/org/jackhuang/hmcl/task/FetchTask.java

@@ -19,6 +19,7 @@ package org.jackhuang.hmcl.task;
 
 import org.jackhuang.hmcl.event.Event;
 import org.jackhuang.hmcl.event.EventBus;
+import org.jackhuang.hmcl.event.EventManager;
 import org.jackhuang.hmcl.util.*;
 import org.jackhuang.hmcl.util.io.ContentEncoding;
 import org.jackhuang.hmcl.util.io.IOUtils;
@@ -355,13 +356,13 @@ public abstract class FetchTask<T> extends Task<T> {
 
     private static final Timer timer = new Timer("DownloadSpeedRecorder", true);
     private static final AtomicLong downloadSpeed = new AtomicLong(0L);
-    public static final EventBus speedEvent = new EventBus();
+    public static final EventManager<SpeedEvent> SPEED_EVENT = EventBus.EVENT_BUS.channel(SpeedEvent.class);
 
     static {
         timer.schedule(new TimerTask() {
             @Override
             public void run() {
-                speedEvent.channel(SpeedEvent.class).fireEvent(new SpeedEvent(speedEvent, downloadSpeed.getAndSet(0)));
+                SPEED_EVENT.fireEvent(new SpeedEvent(SPEED_EVENT, downloadSpeed.getAndSet(0)));
             }
         }, 0, 1000);
     }