/*
* *********************************************************************************************************************
*
* SteelBlue: DCI User Interfaces
* http://tidalwave.it/projects/steelblue
*
* Copyright (C) 2015 - 2023 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 java.lang.reflect.Proxy;
import javax.annotation.Nonnull;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executor;
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.util.ReflectionUtils;
import it.tidalwave.role.ui.javafx.JavaFXBinder;
import it.tidalwave.role.ui.javafx.impl.DefaultJavaFXBinder;
import it.tidalwave.role.ui.javafx.impl.util.JavaFXSafeProxy;
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
*
**********************************************************************************************************************/
@Slf4j
public class JavaFXSafeProxyCreator
{
private static final String P_TIMEOUT = JavaFXSafeProxyCreator.class.getName() + ".initTimeout";
private static final int initializerTimeout = Integer.getInteger(P_TIMEOUT, 10);
public static final Map<Class<?>, Object> BEANS = new HashMap<>();
@Getter
private static final ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
@Getter
private static final JavaFXBinder javaFxBinder = new DefaultJavaFXBinder(executor);
static
{
executor.setWaitForTasksToCompleteOnShutdown(false);
executor.setThreadNamePrefix("javafxBinder-");
// Fix for STB-26
executor.setCorePoolSize(1);
executor.setMaxPoolSize(1);
executor.setQueueCapacity(10000);
BEANS.put(JavaFXBinder.class, javaFxBinder);
BEANS.put(Executor.class, executor);
}
private JavaFXSafeProxyCreator () {}
/*******************************************************************************************************************
*
*
*
******************************************************************************************************************/
@RequiredArgsConstructor(access = PRIVATE)
public static final class NodeAndDelegate
{
@Getter @Nonnull
private final Node node;
@Nonnull
private final Object delegate;
@Nonnull
public <T> T getDelegate()
{
return (T)delegate;
}
@Nonnull
public static <T> NodeAndDelegate load (@Nonnull final Class<T> clazz, @Nonnull final String resource)
throws IOException
{
log.debug("NodeAndDelegate({}, {})", clazz, resource);
assert Platform.isFxApplicationThread() : "Not in JavaFX UI Thread";
final var loader = new FXMLLoader(clazz.getResource(resource), null, null,
type -> ReflectionUtils.instantiateWithDependencies(type, BEANS));
final Node node = loader.load();
final T jfxController = loader.getController();
ReflectionUtils.injectDependencies(jfxController, BEANS);
final var interfaces = jfxController.getClass().getInterfaces();
if (interfaces.length == 0)
{
log.warn("{} has no interface: not creating safe proxy", jfxController.getClass());
log.debug(">>>> load({}, {}) completed", clazz, resource);
return new NodeAndDelegate(node, jfxController);
}
else
{
final var interfaceClass = (Class<T>)interfaces[0]; // FIXME
unchecked cast
final var safeDelegate = JavaFXSafeProxyCreator.createSafeProxy(jfxController, interfaceClass);
log.debug(">>>> load({}, {}) completed", clazz, resource);
return new NodeAndDelegate(node, safeDelegate);
}
}
}
/*******************************************************************************************************************
*
* 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)
{
final var resource = presentationClass.getSimpleName().replaceAll("^JavaFX", "")
.replaceAll("^JavaFx", "")
.replaceAll("Presentation$", "")
+ ".fxml";
return createNodeAndDelegate(presentationClass, resource);
}
/*******************************************************************************************************************
*
* 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)
{
log.debug("createNodeAndDelegate({}, {})", presentationClass, fxmlResourcePath);
final var latch = new CountDownLatch(1);
final var nad = new AtomicReference<NodeAndDelegate>();
final var exception = new AtomicReference<RuntimeException>();
if (Platform.isFxApplicationThread())
{
try
{
return NodeAndDelegate.load(presentationClass, fxmlResourcePath);
}
catch (IOException e)
{
exception.set(new RuntimeException(e));
}
}
Platform.runLater(() ->
{
try
{
nad.set(NodeAndDelegate.load(presentationClass, fxmlResourcePath));
}
catch (RuntimeException e)
{
exception.set(e);
}
catch (Exception e)
{
exception.set(new RuntimeException(e));
}
latch.countDown();
});
try
{
log.debug("Waiting for NodeAndDelegate initialisation in JavaFX thread...");
log.debug("If deadlocks and you need longer time with the debugger, set {} (current value: {})",
P_TIMEOUT, initializerTimeout);
latch.await(initializerTimeout, TimeUnit.SECONDS); // FIXME
}
catch (InterruptedException e)
{
throw new RuntimeException(e);
}
if (exception.get() != null)
{
throw exception.get();
}
if (nad.get() == null)
{
final var message = String.format("Likely deadlock in the JavaFX Thread: couldn't create " +
"NodeAndDelegate: %s, %s", presentationClass, fxmlResourcePath);
throw new RuntimeException(message);
}
return nad.get();
}
/*******************************************************************************************************************
*
*
*
******************************************************************************************************************/
@Nonnull
public static <T> T createSafeProxy (@Nonnull final T target, final Class<T> interfaceClass)
{
return (T)Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),
new Class[] { interfaceClass },
new JavaFXSafeProxy<>(target));
}
}
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