1 /*
2 * *************************************************************************************************************************************************************
3 *
4 * SteelBlue: DCI User Interfaces
5 * http://tidalwave.it/projects/steelblue
6 *
7 * Copyright (C) 2015 - 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/steelblue-src
22 * git clone https://github.com/tidalwave-it/steelblue-src
23 *
24 * *************************************************************************************************************************************************************
25 */
26 package it.tidalwave.ui.javafx;
27
28 import java.lang.reflect.Proxy;
29 import javax.annotation.Nonnull;
30 import java.util.HashMap;
31 import java.util.Map;
32 import java.util.concurrent.CountDownLatch;
33 import java.util.concurrent.Executor;
34 import java.util.concurrent.TimeUnit;
35 import java.util.concurrent.atomic.AtomicReference;
36 import java.io.IOException;
37 import javafx.fxml.FXMLLoader;
38 import javafx.scene.Node;
39 import javafx.application.Platform;
40 import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
41 import it.tidalwave.role.ui.ToolBarModel;
42 import it.tidalwave.role.ui.javafx.JavaFXBinder;
43 import it.tidalwave.role.ui.javafx.impl.DefaultJavaFXBinder;
44 import it.tidalwave.role.ui.javafx.impl.util.JavaFXSafeProxy;
45 import lombok.Getter;
46 import lombok.extern.slf4j.Slf4j;
47
48 /***************************************************************************************************************************************************************
49 *
50 * This facility class create a thread-safe proxy for the JavaFX delegate (controller). Thread-safe means that it can
51 * be called by any thread and the JavaFX UI related stuff will be safely invoked in the JavaFX UI Thread.
52 * It is usually used in this way:
53 *
54 * <pre>
55 * // This is a Spring bean
56 * public class JavaFxFooBarPresentation implements FooBarPresentation
57 * {
58 * private static final String FXML_URL = "/my/package/javafx/FooBar.fxml";
59 *
60 * {@literal @}Inject
61 * private FlowController flowController;
62 *
63 * private final NodeAndDelegate nad = createNodeAndDelegate(getClass(), FXML_URL);
64 *
65 * private final FooBarPresentation delegate = nad.getDelegate();
66 *
67 * public void showUp()
68 * {
69 * flowController.doSomething(nad.getNode());
70 * }
71 *
72 * public void showData (final String data)
73 * {
74 * delegate.showData(data);
75 * }
76 * }
77 * </pre>
78 *
79 * The method {@link #createNodeAndDelegate(java.lang.Class, java.lang.String)} safely invokes the {@link FXMLLoader}
80 * and returns a {@link NodeAndDelegate} that contains both the visual {@link Node} and its delegate (controller).
81 *
82 * The latter is wrapped by a safe proxy that makes sure that any method invocation (such as {@code showData()} in the
83 * example is again executed in the JavaFX UI Thread. This means that the Presentation object methods can be invoked
84 * in any thread.
85 *
86 * For method returning {@code void}, the method invocation is asynchronous; that is, the caller is not blocked waiting
87 * for the method execution completion. If a return value is provided, the invocation is synchronous, and the caller
88 * will correctly wait the completion of the execution in order to get the result value.
89 *
90 * A typical JavaFX delegate (controller) looks like:
91 *
92 * <pre>
93 * // This is not a Spring bean - created by the FXMLLoader
94 * public class JavaFxFooBarPresentationDelegate implements FooBarPresentation
95 * {
96 * {@literal @}FXML
97 * private Label label;
98 *
99 * {@literal @}FXML
100 * private Button button;
101 *
102 * {@literal @}Inject // the only thing that can be injected, by means of JavaFXSafeProxyCreator
103 * private JavaFxBinder binder;
104 *
105 * {@literal @}Override
106 * public void bind (final UserAction action)
107 * {
108 * binder.bind(button, action);
109 * }
110 *
111 * {@literal @}Override
112 * public void showData (final String data)
113 * {
114 * label.setText(data);
115 * }
116 * }
117 * </pre>
118 *
119 * Not only all the methods invoked on the delegate are guaranteed to run in the JavaFX UI thread, but also its
120 * constructor, as per JavaFX requirements.
121 *
122 * A Presentation Delegate must not try to have dependency injection from Spring (for instance, by means of AOP),
123 * otherwise a deadlock could be triggered. Injection in constructors is safe.
124 *
125 * @author Fabrizio Giudici
126 *
127 **************************************************************************************************************************************************************/
128 @Slf4j
129 public class JavaFXSafeProxyCreator
130 {
131 private static final String P_TIMEOUT = JavaFXSafeProxyCreator.class.getName() + ".initTimeout";
132 private static final int initializerTimeout = Integer.getInteger(P_TIMEOUT, 10);
133
134 public static final Map<Class<?>, Object> BEANS = new HashMap<>();
135
136 @Getter
137 private static final ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
138
139 @Getter
140 private static final JavaFXBinder javaFxBinder = new DefaultJavaFXBinder(executor);
141
142 @Getter
143 private static final ToolBarModel toolBarModel = new JavaFXToolBarModel();
144
145 static
146 {
147 executor.setWaitForTasksToCompleteOnShutdown(false);
148 executor.setThreadNamePrefix("javafxBinder-");
149 // Fix for STB-26
150 executor.setCorePoolSize(1);
151 executor.setMaxPoolSize(1);
152 executor.setQueueCapacity(10000);
153 BEANS.put(JavaFXBinder.class, javaFxBinder);
154 BEANS.put(Executor.class, executor);
155 BEANS.put(ToolBarModel.class, toolBarModel);
156 }
157
158 private JavaFXSafeProxyCreator () {}
159
160 /***********************************************************************************************************************************************************
161 * Creates a {@link NodeAndDelegate} for the given presentation class. The FXML resource name is inferred by
162 * default, For instance, is the class is named {@code JavaFXFooBarPresentation}, the resource name is
163 * {@code FooBar.fxml} and searched in the same packages as the class.
164 *
165 * @see #createNodeAndDelegate(java.lang.Class, java.lang.String)
166 *
167 * @since 1.0-ALPHA-13
168 *
169 * @param presentationClass the class of the presentation for which the resources must be created.
170 **********************************************************************************************************************************************************/
171 @Nonnull
172 public static <T> NodeAndDelegate<T> createNodeAndDelegate (@Nonnull final Class<T> presentationClass)
173 {
174 final var resource = presentationClass.getSimpleName().replaceAll("^JavaFX", "")
175 .replaceAll("^JavaFx", "")
176 .replaceAll("Presentation$", "")
177 + ".fxml";
178 return createNodeAndDelegate(presentationClass, resource);
179 }
180
181 /***********************************************************************************************************************************************************
182 * Creates a {@link NodeAndDelegate} for the given presentation class.
183 *
184 * @param presentationClass the class of the presentation for which the resources must be created.
185 * @param fxmlResourcePath the path of the FXML resource
186 **********************************************************************************************************************************************************/
187 @Nonnull
188 public static <T> NodeAndDelegate<T> createNodeAndDelegate (@Nonnull final Class<T> presentationClass, @Nonnull final String fxmlResourcePath)
189 {
190 log.debug("createNodeAndDelegate({}, {})", presentationClass, fxmlResourcePath);
191
192 final var latch = new CountDownLatch(1);
193 final var nad = new AtomicReference<NodeAndDelegate<T>>();
194 final var exception = new AtomicReference<RuntimeException>();
195
196 if (Platform.isFxApplicationThread())
197 {
198 try
199 {
200 return NodeAndDelegate.load(presentationClass, fxmlResourcePath);
201 }
202 catch (IOException e)
203 {
204 exception.set(new RuntimeException(e));
205 }
206 }
207
208 Platform.runLater(() ->
209 {
210 try
211 {
212 nad.set(NodeAndDelegate.load(presentationClass, fxmlResourcePath));
213 }
214 catch (RuntimeException e)
215 {
216 exception.set(e);
217 }
218 catch (Exception e)
219 {
220 exception.set(new RuntimeException(e));
221 }
222
223 latch.countDown();
224 });
225
226 try
227 {
228 log.debug("Waiting for NodeAndDelegate initialisation in JavaFX thread...");
229 log.debug("If deadlocks and you need longer time with the debugger, set {} (current value: {})", P_TIMEOUT, initializerTimeout);
230 latch.await(initializerTimeout, TimeUnit.SECONDS); // FIXME
231 }
232 catch (InterruptedException e)
233 {
234 throw new RuntimeException(e);
235 }
236
237 if (exception.get() != null)
238 {
239 throw exception.get();
240 }
241
242 if (nad.get() == null)
243 {
244 final var message = String.format("Likely deadlock in the JavaFX Thread: couldn't create NodeAndDelegate: %s, %s",
245 presentationClass, fxmlResourcePath);
246 throw new RuntimeException(message);
247 }
248
249 return nad.get();
250 }
251
252 /***********************************************************************************************************************************************************
253 *
254 **********************************************************************************************************************************************************/
255 @Nonnull
256 public static <T> T createSafeProxy (@Nonnull final T target, final Class<T> interfaceClass)
257 {
258 return (T)Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(), new Class[] { interfaceClass }, new JavaFXSafeProxy<>(target));
259 }
260 }