/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
package org.codehaus.groovy.binding;
import groovy.beans.DefaultPropertyAccessor;
import groovy.beans.PropertyAccessor;
import groovy.lang.GroovyRuntimeException;
import groovy.lang.MissingMethodException;
import org.codehaus.groovy.runtime.InvokerHelper;
import org.codehaus.groovy.runtime.InvokerInvocationException;
import org.codehaus.groovy.runtime.ResourceGroovyMethods;
import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;
import javax.swing.SwingUtilities;
import java.awt.Component;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyVetoException;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.net.URL;
import java.util.Enumeration;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* @author <a href="mailto:shemnon@yahoo.com">Danno Ferrin</a>
* @author Andres Almiray
* @since Groovy 1.1
*/
public class PropertyBinding implements SourceBinding, TargetBinding, TriggerBinding {
private static final ExecutorService DEFAULT_EXECUTOR_SERVICE = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
private static final Logger LOG = Logger.getLogger(PropertyBinding.class.getName());
private static final Map<Class, Class<? extends PropertyAccessor>> ACCESSORS = new LinkedHashMap<Class, Class<? extends PropertyAccessor>>();
static {
Enumeration<URL> urls = fetchUrlsFor("META-INF/services/" + groovy.beans.PropertyAccessor.class.getName());
while (urls.hasMoreElements()) {
try {
registerPropertyAccessors(ResourceGroovyMethods.readLines(urls.nextElement()));
} catch (IOException e) {
// ignore
// TODO should use a low priority logger
e.printStackTrace();
}
}
}
private static void registerPropertyAccessors(List<String> lines) {
ClassLoader cl = Thread.currentThread().getContextClassLoader();
for (String line : lines) {
line = line.trim();
if (line.startsWith("#")) return;
String[] parts = line.split("=");
if (parts.length == 2) {
try {
ACCESSORS.put(cl.loadClass(parts[0].trim()), (Class<? extends PropertyAccessor>) cl.loadClass(parts[1].trim()));
} catch (ClassNotFoundException e) {
// ignore
// TODO should use a low priority logger
e.printStackTrace();
}
}
}
}
private static Enumeration<URL> fetchUrlsFor(String path) {
try {
return Thread.currentThread().getContextClassLoader().getResources(path);
} catch (IOException e) {
return new Enumeration<URL>() {
public boolean hasMoreElements() {
return false;
}
public URL nextElement() {
return null;
}
};
}
}
Object bean;
String propertyName;
boolean nonChangeCheck;
UpdateStrategy updateStrategy;
private final Object[] lock = new Object[0];
private PropertyAccessor propertyAccessor;
public PropertyBinding(Object bean, String propertyName) {
this(bean, propertyName, (UpdateStrategy) null);
}
public PropertyBinding(Object bean, String propertyName, String updateStrategy) {
this(bean, propertyName, UpdateStrategy.of(updateStrategy));
}
public PropertyBinding(Object bean, String propertyName, UpdateStrategy updateStrategy) {
this.bean = bean;
this.propertyName = propertyName;
this.updateStrategy = pickUpdateStrategy(bean, updateStrategy);
if (LOG.isLoggable(Level.FINER)) {
LOG.finer("Updating with " + this.updateStrategy + " property '" + propertyName + "' of bean " + bean);
}
setupPropertyReaderAndWriter();
}
private void setupPropertyReaderAndWriter() {
synchronized (lock) {
propertyAccessor = fetchPropertyAccessor(bean != null ? bean.getClass() : null);
}
}
private PropertyAccessor propertyAccessor() {
synchronized (lock) {
return propertyAccessor;
}
}
private PropertyAccessor fetchPropertyAccessor(Class klass) {
if (klass == null) {
return DefaultPropertyAccessor.INSTANCE;
}
Class<? extends PropertyAccessor> accessorClass = ACCESSORS.get(klass);
if (accessorClass == null) {
for (Class c : klass.getInterfaces()) {
PropertyAccessor propertyAccessor = fetchPropertyAccessor(c);
if (propertyAccessor != DefaultPropertyAccessor.INSTANCE) {
return propertyAccessor;
}
}
return fetchPropertyAccessor(klass.getSuperclass());
}
try {
return accessorClass.newInstance();
} catch (InstantiationException e) {
return DefaultPropertyAccessor.INSTANCE;
} catch (IllegalAccessException e) {
return DefaultPropertyAccessor.INSTANCE;
}
}
public UpdateStrategy getUpdateStrategy() {
return updateStrategy;
}
private static UpdateStrategy pickUpdateStrategy(Object bean, UpdateStrategy updateStrategy) {
if (bean instanceof Component) {
return UpdateStrategy.MIXED;
} else if (updateStrategy != null) {
return updateStrategy;
}
return UpdateStrategy.SAME;
}
public void updateTargetValue(final Object newValue) {
Runnable runnable = new Runnable() {
public void run() {
Object sourceValue = getSourceValue();
// if (isNonChangeCheck()) {
if ((sourceValue == null && newValue == null) ||
DefaultTypeTransformation.compareEqual(sourceValue, newValue)) {
// not a change, don't fire it
return;
}
// }
setBeanProperty(newValue);
}
};
switch (updateStrategy) {
case MIXED:
if (SwingUtilities.isEventDispatchThread()) {
runnable.run();
} else {
SwingUtilities.invokeLater(runnable);
}
break;
case ASYNC:
SwingUtilities.invokeLater(runnable);
break;
case SYNC:
if (SwingUtilities.isEventDispatchThread()) {
runnable.run();
} else {
try {
SwingUtilities.invokeAndWait(runnable);
} catch (InterruptedException e) {
LOG.log(Level.WARNING, "Error notifying propertyChangeListener", e);
throw new GroovyRuntimeException(e);
} catch (InvocationTargetException e) {
LOG.log(Level.WARNING, "Error notifying propertyChangeListener", e.getTargetException());
throw new GroovyRuntimeException(e.getTargetException());
}
}
break;
case SAME:
runnable.run();
break;
case OUTSIDE:
if (SwingUtilities.isEventDispatchThread()) {
DEFAULT_EXECUTOR_SERVICE.submit(runnable);
} else {
runnable.run();
}
break;
case DEFER:
DEFAULT_EXECUTOR_SERVICE.submit(runnable);
}
}
private void setBeanProperty(Object newValue) {
try {
propertyAccessor().write(bean, propertyName, newValue);
} catch (InvokerInvocationException iie) {
if (!(iie.getCause() instanceof PropertyVetoException)) {
throw iie;
}
// ignore veto exceptions, just let the binding fail like a validation does
}
}
public boolean isNonChangeCheck() {
synchronized (lock) {
return nonChangeCheck;
}
}
public void setNonChangeCheck(boolean nonChangeCheck) {
synchronized (lock) {
this.nonChangeCheck = nonChangeCheck;
}
}
public Object getSourceValue() {
return propertyAccessor().read(bean, propertyName);
}
public FullBinding createBinding(SourceBinding source, TargetBinding target) {
return new PropertyFullBinding(source, target);
}
class PropertyFullBinding extends AbstractFullBinding implements PropertyChangeListener {
Object boundBean;
Object boundProperty;
boolean bound;
boolean boundToProperty;
PropertyFullBinding(SourceBinding source, TargetBinding target) {
setSourceBinding(source);
setTargetBinding(target);
}
public void propertyChange(PropertyChangeEvent event) {
if (boundToProperty || event.getPropertyName().equals(boundProperty)) {
update();
}
}
public void bind() {
if (!bound) {
bound = true;
boundBean = bean;
boundProperty = propertyName;
try {
InvokerHelper.invokeMethodSafe(boundBean, "addPropertyChangeListener", new Object[]{boundProperty, this});
boundToProperty = true;
} catch (MissingMethodException mme) {
try {
boundToProperty = false;
InvokerHelper.invokeMethodSafe(boundBean, "addPropertyChangeListener", new Object[]{this});
} catch (MissingMethodException mme2) {
throw new RuntimeException("Properties in beans of type " + bean.getClass().getName() + " are not observable in any capacity (no PropertyChangeListener support).");
}
}
}
}
public void unbind() {
if (bound) {
if (boundToProperty) {
try {
InvokerHelper.invokeMethodSafe(boundBean, "removePropertyChangeListener", new Object[]{boundProperty, this});
} catch (MissingMethodException mme) {
// ignore, too bad so sad they don't follow conventions, we'll just leave the listener attached
}
} else {
try {
InvokerHelper.invokeMethodSafe(boundBean, "removePropertyChangeListener", new Object[]{this});
} catch (MissingMethodException mme2) {
// ignore, too bad so sad they don't follow conventions, we'll just leave the listener attached
}
}
boundBean = null;
boundProperty = null;
bound = false;
}
}
public void rebind() {
if (bound) {
unbind();
bind();
}
}
}
public Object getBean() {
return bean;
}
public void setBean(Object bean) {
this.bean = bean;
setupPropertyReaderAndWriter();
}
public String getPropertyName() {
return propertyName;
}
public void setPropertyName(String propertyName) {
this.propertyName = propertyName;
}
public enum UpdateStrategy {
MIXED, ASYNC, SYNC, SAME, OUTSIDE, DEFER;
public static UpdateStrategy of(String str) {
if ("mixed".equalsIgnoreCase(str)) {
return MIXED;
} else if ("async".equalsIgnoreCase(str)) {
return ASYNC;
} else if ("sync".equalsIgnoreCase(str)) {
return SYNC;
} else if ("same".equalsIgnoreCase(str)) {
return SAME;
} else if ("outside".equalsIgnoreCase(str)) {
return OUTSIDE;
} else if ("defer".equalsIgnoreCase(str)) {
return DEFER;
}
return null;
}
}
}