From 69b97a3b2471624a03488405f24608d05ac2e518 Mon Sep 17 00:00:00 2001
From: liujiahua123123 <liujiahua123123@126.com>
Date: Sat, 17 Aug 2019 15:53:38 +0800
Subject: [PATCH] thread safe event system

---
 .../net/mamoe/mirai/event/MiraiEventHook.java | 25 +++++++++++++++++++
 .../mamoe/mirai/event/MiraiEventManager.java  | 25 +++++++++++--------
 .../mamoe/mirai/task/MiraiTaskManager.java    |  6 +++--
 3 files changed, 44 insertions(+), 12 deletions(-)

diff --git a/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventHook.java b/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventHook.java
index 6d39e2c12..a8e6e1936 100644
--- a/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventHook.java
+++ b/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventHook.java
@@ -1,8 +1,10 @@
 package net.mamoe.mirai.event;
 
 import lombok.Getter;
+import lombok.Setter;
 import net.mamoe.mirai.event.events.Cancellable;
 import net.mamoe.mirai.event.events.MiraiEvent;
+import net.mamoe.mirai.event.events.server.ServerDisableEvent;
 
 import java.util.function.Consumer;
 import java.util.function.Predicate;
@@ -21,6 +23,10 @@ public class MiraiEventHook<T extends MiraiEvent> {
     @Getter
     private volatile boolean ignoreCancelled = true;
 
+    @Getter
+    @Setter
+    private volatile boolean mount = false;
+
     /**
      * return true -> this hook need to be removed
      */
@@ -74,4 +80,23 @@ public class MiraiEventHook<T extends MiraiEvent> {
         return this.valid.test((T)event);
     }
 
+    /**
+     * 更加安全高效的方式
+     * Remember to use {@link this.mount()} at last
+     * */
+
+    public static <D extends MiraiEvent> MiraiEventHook<D> onEvent(Class<D> event){
+        return new MiraiEventHook<>(event);
+    }
+
+    public void mount(){
+        MiraiEventManager.getInstance().registerHook(this);
+    }
+
+    public void mountOnce(){
+        MiraiEventManager.getInstance().hookOnce(this);
+    }
+
+
+
 }
diff --git a/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventManager.java b/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventManager.java
index cc7df4418..7eabb7b7d 100644
--- a/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventManager.java
+++ b/mirai-core/src/main/java/net/mamoe/mirai/event/MiraiEventManager.java
@@ -26,17 +26,11 @@ public class MiraiEventManager {
     private Map<Class<? extends MiraiEvent>, List<MiraiEventHook<? extends MiraiEvent>>> hooks = new HashMap<>();
 
     public <D extends MiraiEvent> void hookUntil(MiraiEventHook<D> hook, Predicate<D> toRemove){
-        hooksLock.lock();
-        hooks.putIfAbsent(hook.getEventClass(),new ArrayList<>());
-        hooks.get(hook.getEventClass()).add(hook.setValidUntil(toRemove));
-        hooksLock.unlock();
+        this.mountHook(hook.setValidUntil(toRemove));
     }
 
     public <D extends MiraiEvent> void hookWhile(MiraiEventHook<D> hook, Predicate<D> toKeep){
-        hooksLock.lock();
-        hooks.putIfAbsent(hook.getEventClass(),new ArrayList<>());
-        hooks.get(hook.getEventClass()).add(hook.setValidWhile(toKeep));
-        hooksLock.unlock();
+        this.mountHook(hook.setValidWhile(toKeep));
     }
 
     public <D extends MiraiEvent> void hookOnce(MiraiEventHook<D> hook){
@@ -44,15 +38,25 @@ public class MiraiEventManager {
     }
 
     public <D extends MiraiEvent> void registerHook(MiraiEventHook<D> hook){
-        this.hookUntil(hook,(a) -> false);
+       this.mountHook(hook);
     }
 
+    private <D extends MiraiEvent> void mountHook(MiraiEventHook<D> hook){
+        if(!hook.isMount()) {
+            hook.setMount(true);
+            hooksLock.lock();
+            hooks.putIfAbsent(hook.getEventClass(), new ArrayList<>());
+            hooks.get(hook.getEventClass()).add(hook);
+            hooksLock.unlock();
+        }
+    }
 
     /**
      * 不推荐onEvent
-     * 非线程安全
+     * 由于不能保证Hook的原子性 非线程安全
      * 不能保证下一个 D event发生时handler就位
      * @author NaturalHG Aug27
+     * use {@link MiraiEventHook::onEvent()} to replace
      */
 
     @Deprecated
@@ -85,6 +89,7 @@ public class MiraiEventManager {
 
 
 
+
     public void boardcastEvent(MiraiEvent event){
         hooksLock.lock();
         if(hooks.containsKey(event.getClass())){
diff --git a/mirai-core/src/main/java/net/mamoe/mirai/task/MiraiTaskManager.java b/mirai-core/src/main/java/net/mamoe/mirai/task/MiraiTaskManager.java
index 653d89f13..58cd21e9d 100644
--- a/mirai-core/src/main/java/net/mamoe/mirai/task/MiraiTaskManager.java
+++ b/mirai-core/src/main/java/net/mamoe/mirai/task/MiraiTaskManager.java
@@ -2,6 +2,7 @@ package net.mamoe.mirai.task;
 
 
 import net.mamoe.mirai.MiraiServer;
+import net.mamoe.mirai.event.MiraiEventHook;
 import net.mamoe.mirai.event.events.server.ServerDisableEvent;
 
 import java.util.concurrent.Callable;
@@ -26,9 +27,10 @@ public class MiraiTaskManager {
     private MiraiTaskManager() {
         this.pool = new MiraiThreadPool();
 
-        MiraiServer.getInstance().getEventManager()
+        MiraiEventHook
                 .onEvent(ServerDisableEvent.class)
-                .setHandler(a -> this.pool.close());
+                .setHandler(a -> this.pool.close())
+                .mount();
 
     }