1 /*
2 * *************************************************************************************************************************************************************
3 *
4 * SteelBlue: DCI User Interfaces
5 * http://tidalwave.it/projects/steelblue
6 *
7 * Copyright (C) 2015 - 2025 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.impl.util;
27
28 import java.lang.reflect.InvocationHandler;
29 import java.lang.reflect.Method;
30 import jakarta.annotation.Nonnull;
31 import java.util.concurrent.CountDownLatch;
32 import java.util.concurrent.atomic.AtomicReference;
33 import javafx.application.Platform;
34 import it.tidalwave.ui.javafx.JavaFXSafeProxyCreator;
35 import lombok.Getter;
36 import lombok.RequiredArgsConstructor;
37 import lombok.Setter;
38 import lombok.extern.slf4j.Slf4j;
39
40 /***************************************************************************************************************************************************************
41 *
42 * An {@link InvocationHandler} that safely wraps all method calls with {@link Platform#runLater(Runnable)}. The caller
43 * is not blocked if the method is declared as {@code void}; it is blocked otherwise, so it can immediately retrieve
44 * the result.
45 *
46 * This behaviour is required by {@link JavaFXSafeProxyCreator#createNodeAndDelegate(Class)} ()}.
47 *
48 * TODO: add support for aysnc returning a Future.
49 *
50 * @author Fabrizio Giudici
51 *
52 **************************************************************************************************************************************************************/
53 @RequiredArgsConstructor @Slf4j
54 public class JavaFXSafeProxy<T> implements InvocationHandler
55 {
56 @Nonnull @Getter @Setter
57 private T delegate;
58
59 @Override
60 public Object invoke (@Nonnull final Object proxy, @Nonnull final Method method, @Nonnull final Object[] args)
61 throws Throwable
62 {
63 final var result = new AtomicReference<>();
64 final var throwable = new AtomicReference<Throwable>();
65 final var waitForReturn = new CountDownLatch(1);
66
67 JavaFXSafeRunner.runSafely(() ->
68 {
69 try
70 {
71 log.trace(">>>> safely invoking {}", method);
72 result.set(method.invoke(delegate, args));
73 }
74 catch (Throwable t)
75 {
76 throwable.set(t);
77 log.error("Exception while calling JavaFX", t);
78 }
79 finally
80 {
81 waitForReturn.countDown();
82 }
83 });
84
85 log.trace(">>>> waiting for method completion");
86 waitForReturn.await();
87
88 // This is probably useless - void methods return asynchronously
89 if (throwable.get() != null)
90 {
91 throw throwable.get();
92 }
93
94 return method.getReturnType().equals(void.class) ? null : result.get();
95 }
96 }
97