<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"><html xmlns="http://www.w3.org/1999/xhtml" lang="en"><head><meta http-equiv="Content-Type" content="text/html;charset=UTF-8"/><link rel="stylesheet" href="../jacoco-resources/report.css" type="text/css"/><link rel="shortcut icon" href="../jacoco-resources/report.gif" type="image/gif"/><title>JavaFXSafeProxyCreator.java</title><link rel="stylesheet" href="../jacoco-resources/prettify.css" type="text/css"/><script type="text/javascript" src="../jacoco-resources/prettify.js"></script></head><body onload="window['PR_TAB_WIDTH']=4;prettyPrint()"><div class="breadcrumb" id="breadcrumb"><span class="info"><a href="../jacoco-sessions.html" class="el_session">Sessions</a></span><a href="../index.html" class="el_report">SteelBlue - JavaFX Bindings</a> > <a href="index.source.html" class="el_package">it.tidalwave.ui.javafx</a> > <span class="el_source">JavaFXSafeProxyCreator.java</span></div><h1>JavaFXSafeProxyCreator.java</h1><pre class="source lang-java linenums">/*
* *********************************************************************************************************************
*
* SteelBlue: DCI User Interfaces
* http://tidalwave.it/projects/steelblue
*
* Copyright (C) 2015 - 2021 by Tidalwave s.a.s. (http://tidalwave.it)
*
* *********************************************************************************************************************
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 CONDITIONS OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*
* *********************************************************************************************************************
*
* git clone https://bitbucket.org/tidalwave/steelblue-src
* git clone https://github.com/tidalwave-it/steelblue-src
*
* *********************************************************************************************************************
*/
package it.tidalwave.ui.javafx;
import javax.annotation.Nonnull;
import java.lang.reflect.Proxy;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.Executor;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicReference;
import java.io.IOException;
import javafx.fxml.FXMLLoader;
import javafx.scene.Node;
import javafx.application.Platform;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
import it.tidalwave.role.ui.javafx.JavaFXBinder;
import it.tidalwave.role.ui.javafx.impl.util.JavaFXSafeProxy;
import it.tidalwave.role.ui.javafx.impl.DefaultJavaFXBinder;
import it.tidalwave.role.ui.javafx.impl.util.ReflectionUtils;
import lombok.Getter;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import static lombok.AccessLevel.PRIVATE;
/***********************************************************************************************************************
*
* This facility class create a thread-safe proxy for the JavaFX delegate (controller). Thread-safe means that it can
* be called by any thread and the JavaFX UI related stuff will be safely invoked in the JavaFX UI Thread.
* It is usually used in this way:
*
* <pre>
* // This is a Spring bean
* public class JavaFxFooBarPresentation implements FooBarPresentation
* {
* private static final String FXML_URL = "/my/package/javafx/FooBar.fxml";
*
* @Inject
* private FlowController flowController;
*
* private final NodeAndDelegate nad = createNodeAndDelegate(getClass(), FXML_URL);
*
* private final FooBarPresentation delegate = nad.getDelegate();
*
* public void showUp()
* {
* flowController.doSomething(nad.getNode());
* }
*
* public void showData (final String data)
* {
* delegate.showData(data);
* }
* }
* </pre>
*
* The method {@link #createNodeAndDelegate(java.lang.Class, java.lang.String)} safely invokes the {@link FXMLLoader}
* and returns a {@link NodeAndDelegate} that contains both the visual {@link Node} and its delegate (controller).
*
* The latter is wrapped by a safe proxy that makes sure that any method invocation (such as {@code showData()} in the
* example is again executed in the JavaFX UI Thread. This means that the Presentation object methods can be invoked
* in any thread.
*
* For method returning {@code void}, the method invocation is asynchronous; that is, the caller is not blocked waiting
* for the method execution completion. If a return value is provided, the invocation is synchronous, and the caller
* will correctly wait the completion of the execution in order to get the result value.
*
* A typical JavaFX delegate (controller) looks like:
*
* <pre>
* // This is not a Spring bean - created by the FXMLLoader
* public class JavaFxFooBarPresentationDelegate implements FooBarPresentation
* {
* @FXML
* private Label label;
*
* @FXML
* private Button button;
*
* @Inject // the only thing that can be injected, by means of JavaFXSafeProxyCreator
* private JavaFxBinder binder;
*
* @Override
* public void bind (final UserAction action)
* {
* binder.bind(button, action);
* }
*
* @Override
* public void showData (final String data)
* {
* label.setText(data);
* }
* }
* </pre>
*
* Not only all the methods invoked on the delegate are guaranteed to run in the JavaFX UI thread, but also its
* constructor, as per JavaFX requirements.
*
* A Presentation Delegate must not try to have dependency injection from Spring (for instance, by means of AOP),
* otherwise a deadlock could be triggered. Injection in constructors is safe.
*
* @author Fabrizio Giudici
*
**********************************************************************************************************************/
<span class="nc" id="L131">@Slf4j</span>
public class JavaFXSafeProxyCreator
{
<span class="nc" id="L134"> private static final String P_TIMEOUT = JavaFXSafeProxyCreator.class.getName() + ".initTimeout";</span>
<span class="nc" id="L135"> private static final int initializerTimeout = Integer.getInteger(P_TIMEOUT, 10);</span>
<span class="nc" id="L137"> public static final Map<Class<?>, Object> BEANS = new HashMap<>();</span>
<span class="nc" id="L139"> @Getter</span>
<span class="nc" id="L140"> private static final ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();</span>
<span class="nc" id="L142"> @Getter</span>
<span class="nc" id="L143"> private static final JavaFXBinder javaFxBinder = new DefaultJavaFXBinder(executor);</span>
static
{
<span class="nc" id="L147"> executor.setWaitForTasksToCompleteOnShutdown(false);</span>
<span class="nc" id="L148"> executor.setThreadNamePrefix("javafxBinder-");</span>
// Fix for STB-26
<span class="nc" id="L150"> executor.setCorePoolSize(1);</span>
<span class="nc" id="L151"> executor.setMaxPoolSize(1);</span>
<span class="nc" id="L152"> executor.setQueueCapacity(10000);</span>
<span class="nc" id="L153"> BEANS.put(JavaFXBinder.class, javaFxBinder);</span>
<span class="nc" id="L154"> BEANS.put(Executor.class, executor);</span>
<span class="nc" id="L155"> }</span>
private JavaFXSafeProxyCreator () {}
/*******************************************************************************************************************
*
*
*
******************************************************************************************************************/
<span class="nc bnc" id="L164" title="All 6 branches missed."> @RequiredArgsConstructor(access = PRIVATE)</span>
public static final class NodeAndDelegate
{
<span class="nc" id="L167"> @Getter @Nonnull</span>
private final Node node;
@Nonnull
private final Object delegate;
@Nonnull
public <T> T getDelegate()
{
<span class="nc" id="L176"> return (T)delegate;</span>
}
@Nonnull
public static <T> NodeAndDelegate load (@Nonnull final Class<T> clazz, @Nonnull final String resource)
throws IOException
{
<span class="nc" id="L183"> log.debug("NodeAndDelegate({}, {})", clazz, resource);</span>
<span class="nc bnc" id="L184" title="All 4 branches missed."> assert Platform.isFxApplicationThread() : "Not in JavaFX UI Thread";</span>
<span class="nc" id="L185"> final FXMLLoader loader = new FXMLLoader(clazz.getResource(resource), null, null,</span>
<span class="nc" id="L186"> type -> ReflectionUtils.instantiateWithDependencies(type, BEANS));</span>
<span class="nc" id="L187"> final Node node = (Node)loader.load();</span>
<span class="nc" id="L188"> final T jfxController = loader.getController();</span>
<span class="nc" id="L189"> ReflectionUtils.injectDependencies(jfxController, BEANS);</span>
<span class="nc" id="L190"> final Class<?>[] interfaces = jfxController.getClass().getInterfaces();</span>
<span class="nc bnc" id="L192" title="All 2 branches missed."> if (interfaces.length == 0)</span>
{
<span class="nc" id="L194"> log.warn("{} has no interface: not creating safe proxy", jfxController.getClass());</span>
<span class="nc" id="L195"> log.debug(">>>> load({}, {}) completed", clazz, resource);</span>
<span class="nc" id="L196"> return new NodeAndDelegate(node, jfxController);</span>
}
else
{
<span class="nc" id="L200"> final Class<T> interfaceClass = (Class<T>)interfaces[0]; // FIXME</span>
<span class="nc" id="L201"> final T safeDelegate = JavaFXSafeProxyCreator.createSafeProxy(jfxController, interfaceClass);</span>
<span class="nc" id="L202"> log.debug(">>>> load({}, {}) completed", clazz, resource);</span>
<span class="nc" id="L203"> return new NodeAndDelegate(node, safeDelegate);</span>
}
}
}
/*******************************************************************************************************************
*
* Creates a {@link NodeAndDelegate} for the given presentation class. The FXML resource name is inferred by
* default, For instance, is the class is named {@code JavaFXFooBarPresentation}, the resource name is
* {@code FooBar.fxml} and searched in the same packages as the class.
*
* @see #createNodeAndDelegate(java.lang.Class, java.lang.String)
*
* @since 1.0-ALPHA-13
*
* @param presentationClass the class of the presentation for which the resources must be created.
*
******************************************************************************************************************/
@Nonnull
public static <T> NodeAndDelegate createNodeAndDelegate (@Nonnull final Class<?> presentationClass)
{
<span class="nc" id="L224"> final String resource = presentationClass.getSimpleName().replaceAll("^JavaFX", "")</span>
<span class="nc" id="L225"> .replaceAll("^JavaFx", "")</span>
<span class="nc" id="L226"> .replaceAll("Presentation$", "")</span>
+ ".fxml";
<span class="nc" id="L228"> return createNodeAndDelegate(presentationClass, resource);</span>
}
/*******************************************************************************************************************
*
* Creates a {@link NodeAndDelegate} for the given presentation class.
*
* @param presentationClass the class of the presentation for which the resources must be created.
* @param fxmlResourcePath the path of the FXML resource
*
******************************************************************************************************************/
@Nonnull
public static <T> NodeAndDelegate createNodeAndDelegate (@Nonnull final Class<?> presentationClass,
@Nonnull final String fxmlResourcePath)
{
<span class="nc" id="L243"> log.debug("createNodeAndDelegate({}, {})", presentationClass, fxmlResourcePath);</span>
<span class="nc" id="L245"> final CountDownLatch latch = new CountDownLatch(1);</span>
<span class="nc" id="L246"> final AtomicReference<NodeAndDelegate> nad = new AtomicReference<>();</span>
<span class="nc" id="L247"> final AtomicReference<RuntimeException> exception = new AtomicReference<>();</span>
<span class="nc bnc" id="L249" title="All 2 branches missed."> if (Platform.isFxApplicationThread())</span>
{
try
{
<span class="nc" id="L253"> return NodeAndDelegate.load(presentationClass, fxmlResourcePath);</span>
}
<span class="nc" id="L255"> catch (IOException e)</span>
{
<span class="nc" id="L257"> exception.set(new RuntimeException(e));</span>
}
}
<span class="nc" id="L261"> Platform.runLater(() -></span>
{
try
{
<span class="nc" id="L265"> nad.set(NodeAndDelegate.load(presentationClass, fxmlResourcePath));</span>
}
<span class="nc" id="L267"> catch (RuntimeException e)</span>
{
<span class="nc" id="L269"> exception.set(e);</span>
}
<span class="nc" id="L271"> catch (Exception e)</span>
{
<span class="nc" id="L273"> exception.set(new RuntimeException(e));</span>
<span class="nc" id="L274"> }</span>
<span class="nc" id="L276"> latch.countDown();</span>
<span class="nc" id="L277"> });</span>
try
{
<span class="nc" id="L281"> log.debug("Waiting for NodeAndDelegate initialisation in JavaFX thread...");</span>
<span class="nc" id="L282"> log.debug("If deadlocks and you need longer time with the debugger, set {} (current value: {})",</span>
<span class="nc" id="L283"> P_TIMEOUT, initializerTimeout);</span>
<span class="nc" id="L284"> latch.await(initializerTimeout, TimeUnit.SECONDS); // FIXME</span>
}
<span class="nc" id="L286"> catch (InterruptedException e)</span>
{
<span class="nc" id="L288"> throw new RuntimeException(e);</span>
<span class="nc" id="L289"> }</span>
<span class="nc bnc" id="L291" title="All 2 branches missed."> if (exception.get() != null)</span>
{
<span class="nc" id="L293"> throw exception.get();</span>
}
<span class="nc bnc" id="L296" title="All 2 branches missed."> if (nad.get() == null)</span>
{
<span class="nc" id="L298"> final String message = String.format("Likely deadlock in the JavaFX Thread: couldn't create " +</span>
"NodeAndDelegate: %s, %s", presentationClass, fxmlResourcePath);
<span class="nc" id="L300"> throw new RuntimeException(message);</span>
}
<span class="nc" id="L303"> return nad.get();</span>
}
/*******************************************************************************************************************
*
*
*
******************************************************************************************************************/
@Nonnull
public static <T> T createSafeProxy (@Nonnull final T target, final Class<T> interfaceClass)
{
<span class="nc" id="L314"> return (T)Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),</span>
new Class[] { interfaceClass },
new JavaFXSafeProxy<>(target));
}
}
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