1 /*
2 * *************************************************************************************************************************************************************
3 *
4 * TheseFoolishThings: Miscellaneous utilities
5 * http://tidalwave.it/projects/thesefoolishthings
6 *
7 * Copyright (C) 2009 - 2024 by Tidalwave s.a.s. (http://tidalwave.it)
8 *
9 * *************************************************************************************************************************************************************
10 *
11 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
12 * You may obtain a copy of the License at
13 *
14 * http://www.apache.org/licenses/LICENSE-2.0
15 *
16 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
17 * CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
18 *
19 * *************************************************************************************************************************************************************
20 *
21 * git clone https://bitbucket.org/tidalwave/thesefoolishthings-src
22 * git clone https://github.com/tidalwave-it/thesefoolishthings-src
23 *
24 * *************************************************************************************************************************************************************
25 */
26 package it.tidalwave.actor.spi;
27
28 import java.lang.reflect.InvocationTargetException;
29 import javax.annotation.Nonnegative;
30 import javax.annotation.Nonnull;
31 import it.tidalwave.actor.annotation.Actor;
32 import it.tidalwave.actor.impl.CollaborationAwareMessageBusAdapter;
33 import it.tidalwave.actor.impl.ExecutorWithPriority;
34 import it.tidalwave.actor.impl.MBeansManager;
35 import it.tidalwave.actor.impl.PostConstructInvoker;
36 import it.tidalwave.actor.impl.PreDestroyInvoker;
37 import lombok.Getter;
38 import lombok.extern.slf4j.Slf4j;
39 import static it.tidalwave.messagebus.spi.ReflectionUtils.*;
40
41 /***************************************************************************************************************************************************************
42 *
43 * This class is used to activate and deactivate an actor.
44 *
45 * @author Fabrizio Giudici
46 *
47 **************************************************************************************************************************************************************/
48 @Slf4j
49 public class ActorActivator
50 {
51 @Nonnull
52 private final Class<?> actorClass;
53
54 @Nonnegative @Getter
55 private final int poolSize;
56
57 @Getter
58 private Object actorObject;
59
60 private ExecutorWithPriority executor;
61
62 private CollaborationAwareMessageBusAdapter messageBusAdapter;
63
64 private MBeansManager mBeansManager;
65
66 /***********************************************************************************************************************************************************
67 * Creates an instance for the given actor class.
68 *
69 * @param actorClass the actor class
70 * @return the instance
71 **********************************************************************************************************************************************************/
72 public static ActorActivator activatorFor (@Nonnull final Class<?> actorClass)
73 {
74 return new ActorActivator(actorClass, 1);
75 }
76
77 /***********************************************************************************************************************************************************
78 * Specifies the pool size for this activator.
79 *
80 * @param poolSize the pool size
81 * @return the activator
82 **********************************************************************************************************************************************************/
83 @Nonnull
84 public ActorActivator withPoolSize (@Nonnegative final int poolSize)
85 {
86 return new ActorActivator(actorClass, poolSize);
87 }
88
89 /***********************************************************************************************************************************************************
90 *
91 **********************************************************************************************************************************************************/
92 private ActorActivator (@Nonnull final Class<?> actorClass, @Nonnegative final int poolSize)
93 {
94 this.actorClass = actorClass;
95 this.poolSize = poolSize;
96 }
97
98 /***********************************************************************************************************************************************************
99 * Activates the managed actor.
100 **********************************************************************************************************************************************************/
101 public void initialize()
102 {
103 try
104 {
105 final var actor = actorClass.getAnnotation(Actor.class);
106 validate(actor);
107 actorObject = actorClass.getDeclaredConstructor().newInstance();
108 executor = new ExecutorWithPriority(poolSize, actorClass.getSimpleName(), actor.initialPriority());
109 mBeansManager = new MBeansManager(actorObject, poolSize);
110 messageBusAdapter = new CollaborationAwareMessageBusAdapter(actorObject, executor, mBeansManager.getStats());
111 }
112 catch (InstantiationException | IllegalAccessException | NoSuchMethodException | InvocationTargetException e)
113 {
114 throw new RuntimeException(e);
115 }
116
117 forEachMethodInTopDownHierarchy(actorObject, messageBusAdapter);
118 forEachMethodInTopDownHierarchy(actorObject, new PostConstructInvoker(actorObject));
119 mBeansManager.register();
120 }
121
122 /***********************************************************************************************************************************************************
123 * Deactivates the managed actor and releases resources.
124 **********************************************************************************************************************************************************/
125 public void dispose()
126 {
127 mBeansManager.unregister();
128 forEachMethodInBottomUpHierarchy(actorObject, new PreDestroyInvoker(actorObject));
129 messageBusAdapter.unsubscribe();
130 }
131
132 /***********************************************************************************************************************************************************
133 *
134 **********************************************************************************************************************************************************/
135 private void validate (@Nonnull final Actor actor)
136 {
137 //noinspection ConstantConditions
138 if (actor == null)
139 {
140 throw new IllegalArgumentException("Actor class must be annotated with @Actor: " + actorClass);
141 }
142
143 if (!actor.threadSafe() && (poolSize != 1))
144 {
145 throw new IllegalArgumentException("Actors that aren't thread safe can't have pool size > 1");
146 }
147 }
148 }