/*
* Copyright (C) 2011 Red Hat, Inc. and/or its affiliates.
*
* 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.
*/
package org.jboss.errai.databinding.client;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Supplier;
import org.jboss.errai.common.client.api.Assert;
import org.jboss.errai.common.client.api.IsElement;
import org.jboss.errai.common.client.ui.ElementWrapperWidget;
import org.jboss.errai.databinding.client.api.Convert;
import org.jboss.errai.databinding.client.api.Converter;
import org.jboss.errai.databinding.client.api.DataBinder;
import org.jboss.errai.databinding.client.api.StateSync;
import org.jboss.errai.databinding.client.api.handler.list.BindableListChangeHandler;
import org.jboss.errai.databinding.client.api.handler.property.PropertyChangeEvent;
import org.jboss.errai.databinding.client.api.handler.property.PropertyChangeHandler;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.Multimap;
import com.google.gwt.core.client.JavaScriptException;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.InputElement;
import com.google.gwt.dom.client.Node;
import com.google.gwt.dom.client.TextAreaElement;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.event.logical.shared.ValueChangeEvent;
import com.google.gwt.event.logical.shared.ValueChangeHandler;
import com.google.gwt.event.shared.GwtEvent;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.user.client.TakesValue;
import com.google.gwt.user.client.ui.HasHTML;
import com.google.gwt.user.client.ui.HasText;
import com.google.gwt.user.client.ui.HasValue;
import com.google.gwt.user.client.ui.ValueBoxBase;
import com.google.gwt.user.client.ui.Widget;
/**
* Manages bindings and acts in behalf of a {@link BindableProxy} to keep the target model and bound widgets in sync.
* <p>
* An agent will:
* <ul>
* <li>Carry out an initial state sync between the bound widgets and the target model, if specified (see
* {@link DataBinder#setModel(Object, StateSync)})</li>
*
* <li>Update the bound widget when a setter method is invoked on the model (see
* {@link #updateWidgetsAndFireEvent(boolean, String, Object, Object)}). Works for components that either implement
* {@link TakesValue} or {@link HasText}). Also works for native wrappers of input elements. Components displaying lists
* can implement {@link BindableListChangeHandler} to receive incremental updates of the model state.</li>
*
* <li>Update the bound components when a non-accessor method is invoked on the model (by comparing all bound properties
* to detect changes). See {@link #updateWidgetsAndFireEvents()}. Works for components that either implement
* {@link TakesValue} or {@link HasText})</li>
*
* <li>Update the target model in response to value change events (only works for bound components that implement
* {@link HasValue})</li>
* <ul>
*
* @author Christian Sadilek <csadilek@redhat.com>
* @author Max Barkley <mbarkley@redhat.com>
*
* @param <T>
* The type of the target model being proxied.
*
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
public final class BindableProxyAgent<T> implements HasPropertyChangeHandlers {
private static final Logger logger = LoggerFactory.getLogger(BindableProxyAgent.class);
final Multimap<String, Binding> bindings = LinkedHashMultimap.create();
final Map<String, PropertyType> propertyTypes = new HashMap<>();
final Map<String, DataBinder> binders = new HashMap<>();
final Map<String, Object> knownValues = new HashMap<>();
final Collection<HandlerRegistration> modelChangeHandlers = new ArrayList<>();
PropertyChangeHandlerSupport propertyChangeHandlerSupport = new PropertyChangeHandlerSupport();
final BindableProxy<T> proxy;
T target;
BindableProxyAgent(final BindableProxy<T> proxy, final T target) {
this.proxy = proxy;
this.target = target;
}
/**
* Copies the values of all properties to be able to compare them in case they
* change outside a setter method.
*/
void copyValues() {
for (final String property : propertyTypes.keySet()) {
if (!"this".equals(property)) {
knownValues.put(property, proxy.get(property));
}
}
}
/**
* Binds the provided component to the specified property (or property chain) of the model instance associated with
* this proxy (see {@link DataBinder#setModel(Object, StateSync)}).
*
* @param component
* the UI component to bind to, must not be null.
* @param property
* the property of the model to bind the widget to, must not be null.
* @param converter
* the converter to use for this binding, null if default conversion should be used. See
* {@link Convert#getConverter(Class, Class)} and {@link Convert#identityConverter(Class)} for possible
* arguments.
* @return binding the created binding.
*/
public Binding bind(final Object component, final String property, final Converter converter) {
return bind(component, property, converter, false, StateSync.FROM_MODEL);
}
/**
* Binds the provided component to the specified property (or property chain) of the model instance associated with
* this proxy (see {@link DataBinder#setModel(Object, StateSync)}).
*
* @param component
* the UI component to bind to, must not be null.
* @param property
* the property of the model to bind the widget to, must not be null.
* @param providedConverter
* the converter to use for this binding, null if default conversion should be used. See
* {@link Convert#getConverter(Class, Class)} and {@link Convert#identityConverter(Class)} for possible
* arguments.
* @param bindOnKeyUp
* a flag indicating that the property should be updated when the widget fires a
* {@link com.google.gwt.event.dom.client.KeyUpEvent} along with the default
* {@link com.google.gwt.event.logical.shared.ValueChangeEvent}.
* @param initialState
* specifies whether to use the model or component state when initially synchronizing this binding. If null,
* the values will not be synchronized until a change is made to the model or component.
* @return binding the created binding.
*/
public Binding bind(final Object component, final String property, final Converter providedConverter,
final boolean bindOnKeyUp, final StateSync initialState) {
logger.debug("Binding property {} to component {}", property, component);
final Converter converter = findConverter(property, getPropertyType(property).getType(), component, providedConverter);
logger.debug("Using converter: {} <--> {}", converter.getModelType().getSimpleName(), converter.getComponentType().getSimpleName());
final String lastSubProperty = property.substring(property.lastIndexOf('.')+1);
final Optional<Supplier<Object>> uiGetter = maybeCreateUIGetter(component);
final Function<BindableProxyAgent<?>, Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>>> registrar =
agent -> addHandlers(component, bindOnKeyUp, uiGetter, modelUpdater(component, converter, lastSubProperty, agent));
return bindHelper(component, property, converter, registrar, uiGetter, initialState);
}
private Optional<Supplier<Object>> maybeCreateUIGetter(final Object component) {
if (component instanceof TakesValue) {
return createTakesValueGetter((TakesValue) component);
}
else if (component instanceof HasText) {
return createHasTextGetter((HasText) component);
}
else if (component instanceof IsElement) {
return maybeCreateElementValueGetter(BoundUtil.asElement(((IsElement) component).getElement()));
}
else if (isElement(component)) {
return maybeCreateElementValueGetter(BoundUtil.asElement(component));
}
else {
return Optional.empty();
}
}
private Consumer<Object> modelUpdater(final Object component, final Converter converter, final String lastSubProperty,
final BindableProxyAgent<?> agent) {
return uiValue -> {
final Object oldValue = agent.proxy.get(lastSubProperty);
final Object newValue = converter.toModelValue(uiValue);
agent.trySettingModelProperty(lastSubProperty, converter, uiValue, newValue);
agent.updateWidgetsAndFireEvent(false, lastSubProperty, oldValue, newValue, component);
};
}
private Optional<Supplier<Object>> createTakesValueGetter(final TakesValue component) {
return Optional.ofNullable(() -> component.getValue());
}
private Optional<Supplier<Object>> createHasTextGetter(final HasText component) {
return Optional.ofNullable(() -> component.getText());
}
private Optional<Supplier<Object>> maybeCreateElementValueGetter(final Element element) {
final Optional<Supplier<Object>> uiGetter;
final Supplier<ElementWrapperWidget> toWidget = () -> ElementWrapperWidget.getWidget(element);
final ElementWrapperWidget wrapper = toWidget.get();
if (wrapper instanceof HasValue) {
uiGetter = Optional.ofNullable(() -> ((HasValue) toWidget.get()).getValue());
}
else if (wrapper instanceof HasHTML) {
uiGetter = Optional.ofNullable(() -> ((HasHTML) toWidget.get()).getText());
}
else {
uiGetter = Optional.empty();
}
return uiGetter;
}
private Binding bindHelper(final Object component, final String property, final Converter converter,
final Function<BindableProxyAgent<?>, Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>>> registrar,
final Optional<Supplier<Object>> uiGetter, final StateSync initialState) {
validatePropertyExpr(property);
if (property.contains(".")) {
return bindNestedProperty(component, property, converter, registrar, uiGetter, initialState);
}
else {
return bindDirectProperty(component, property, converter, registrar.apply(this), uiGetter, initialState);
}
}
private Binding bindNestedProperty(final Object component, final String property, final Converter<?, ?> converter,
final Function<BindableProxyAgent<?>, Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>>> registrar,
final Optional<Supplier<Object>> uiGetter, final StateSync initialState) {
final DataBinder nestedBinder = createNestedBinder(property, initialState);
final String subProperty = property.substring(property.indexOf('.') + 1);
final BindableProxyAgent<?> nestedAgent = ((BindableProxy<?>) nestedBinder.getModel()).getBindableProxyAgent();
nestedBinder.addBinding(subProperty, nestedAgent.bindHelper(component, subProperty, converter, registrar, uiGetter, initialState));
final Binding binding = new Binding(property, component, converter, null);
bindings.put(property, binding);
return binding;
}
private void trySettingModelProperty(final String property, final Converter converter, final Object uiValue,
final Object newValue) {
try {
proxy.set(property, newValue);
} catch (final Throwable t) {
if (newValue == null && isCausedByNullOrUndefined(t)) {
/*
* Don't fail here because likely this is an error from trying to unbox a null value to a primitive.
* XXX Maybe we should check for boxed types before trying to set the property.
*/
logger.warn("Encountered a null while trying to set the property [" + property + "] to ["
+ newValue + "].", t);
}
else {
throw new RuntimeException("Error while setting property [" + property + "] to [" + newValue
+ "] converted from [" + uiValue + "] with converter [" + converter.getComponentType().getName() + " -> "
+ converter.getModelType().getName() + "].", t);
}
}
}
private boolean isCausedByNullOrUndefined(final Throwable t) {
return t instanceof NullPointerException
|| (t instanceof JavaScriptException && t.getMessage().contains("null"));
}
private PropertyType getPropertyType(final String property) {
return getPropertyType(proxy, property);
}
private static PropertyType getPropertyType(final BindableProxy<?> proxy, final String property) {
final BindableProxyAgent<?> agent = proxy.getBindableProxyAgent();
if (property.contains(".")) {
final int firstDot = property.indexOf(".");
final String topLevelProperty = property.substring(0, firstDot);
final String childProperty = property.substring(firstDot+1);
final PropertyType topLevelType = getPropertyType(proxy, topLevelProperty);
final BindableProxy<?> topLevelProxy;
if (topLevelType instanceof MapPropertyType) {
topLevelProxy = (BindableProxy<?>) DataBinder.forMap(((MapPropertyType) topLevelType).getPropertyTypes()).getModel();
}
else {
topLevelProxy = BindableProxyFactory.getBindableProxy(topLevelType.getType().getName());
}
return getPropertyType(topLevelProxy, childProperty);
}
else if (agent.propertyTypes.containsKey(property)) {
return agent.propertyTypes.get(property);
}
else {
final String type = proxy.getClass().getSuperclass().getSimpleName();
throw new NonExistingPropertyException(type, property);
}
}
private Binding bindDirectProperty(final Object component, final String property, final Converter converter,
final Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> handlerRegistrar,
final Optional<Supplier<Object>> uiGetter, final StateSync initialState) {
checkComponentNotAlreadyBound(component, property);
final Binding binding = createBinding(component, property, converter, handlerRegistrar);
syncState(component, property, converter, uiGetter, initialState);
return binding;
}
private Binding createBinding(final Object component, final String property, final Converter converter,
final Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> handlerRegistrar) {
final Binding binding = new Binding(property, component, converter, handlerRegistrar.get());
bindings.put(property, binding);
if (propertyTypes.get(property).isList()) {
if ("this".equals(property) && proxy instanceof BindableListWrapper) {
addHandlersForBindableListWrapper("this", (BindableListWrapper) proxy);
}
else {
proxy.set(property, ensureBoundListIsProxied(property));
}
}
return binding;
}
private void checkComponentNotAlreadyBound(final Object component, final String property) {
for (final Binding binding : bindings.values()) {
if (binding.getComponent().equals(component) && !property.equals(binding.getProperty())) {
throw new ComponentAlreadyBoundException("Widget already bound to property: " + binding.getProperty());
}
}
}
private Converter findConverter(final String property, final Class<?> propertyType, final Object component, final Converter userProvidedConverter) {
final Optional<Class<?>> componentValueType;
if (component instanceof Widget) {
final Class<?> presumedType = (userProvidedConverter == null) ? propertyType : userProvidedConverter.getComponentType();
componentValueType = Optional.ofNullable(Convert.inferWidgetValueType((Widget) component, presumedType));
}
else if (isElement(component)) {
final Element element = BoundUtil.asElement(component);
if (InputElement.is(element)) {
componentValueType = Optional.ofNullable(ElementWrapperWidget.getValueClassForInputType(element.getPropertyString("type")));
}
else if (TextAreaElement.is(element)) {
componentValueType = Optional.ofNullable(String.class);
}
else {
componentValueType = Optional.empty();
}
}
else {
componentValueType = Optional.empty();
}
if (userProvidedConverter != null) {
validateTypes(property, propertyType, userProvidedConverter.getModelType(), "model");
componentValueType.ifPresent(t -> validateTypes(property, t, userProvidedConverter.getComponentType(), "widget"));
return userProvidedConverter;
}
else {
final Class<?> effectiveComponentType = componentValueType.orElse(String.class);
final Converter<?, ?> converter = Convert.getConverter(propertyType, effectiveComponentType);
if (converter == null) {
throw new RuntimeException(
"Cannot convert between " + propertyType.getName() + " and " + effectiveComponentType.getName()
+ " for property [" + property + "] in " + proxy.unwrap().getClass().getName());
}
return converter;
}
}
private void validateTypes(final String property, final Class<?> actualType, final Class<?> converterType, final String modelOrWidget) {
if (!actualType.equals(converterType) && !oneTypeIsInterface(actualType, converterType)) {
throw new RuntimeException("Converter " + modelOrWidget + " type, " + converterType.getName()
+ ", does not match the required type, " + actualType.getName());
}
}
private boolean oneTypeIsInterface(final Class<?> propertyType, final Class<?> converterModelType) {
return propertyType.isInterface() || converterModelType.isInterface();
}
/**
* Makes a supplier for adding the required event handlers to the provided component. A {@link ValueChangeHandler} is
* added by default, a {@link KeyUpHandler} is added if bindOnKeyUp is true.
*
* @param component
* the bound UI component, must not be null.
* @param bindOnKeyUp
* a flag indicating that the property should be updated when the widget fires a
* {@link com.google.gwt.event.dom.client.KeyUpEvent} , in addition to the default
* {@link com.google.gwt.event.logical.shared.ValueChangeEvent}.
* @param uiGetter
* an optional function for extracting the UI component value.
* @param modelUpdater
* A {@link Consumer<?>} that updates the bound property of the model in response to UI changes.
* @return a supplier that registers handlers and returns a collection of event handler registrations.
*/
private static Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> addHandlers(
final Object component, final boolean bindOnKeyUp, final Optional<Supplier<Object>> uiGetter,
final Consumer<Object> modelUpdater) {
checkWidgetHasTextOrValue(component);
Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> registrar = () -> new HashMap<>();
if (component instanceof HasValue) {
registrar = mergeHasValueChangeHandler(component, modelUpdater, registrar);
}
else if (component instanceof IsElement) {
registrar = mergeNativeChangeEventListener(((IsElement) component).getElement(), uiGetter, modelUpdater, registrar);
}
else if (isElement(component)) {
registrar = mergeNativeChangeEventListener(component, uiGetter, modelUpdater, registrar);
}
if (bindOnKeyUp) {
if (component instanceof ValueBoxBase) {
registrar = mergeValueBoxKeyUpHandler(component, modelUpdater, registrar);
}
else if (component instanceof ElementWrapperWidget) {
registrar = mergeNativeKeyUpEventListener(((ElementWrapperWidget) component).getElement(), uiGetter, modelUpdater, registrar);
}
else if (component instanceof IsElement) {
registrar = mergeNativeKeyUpEventListener(((IsElement) component).getElement(), uiGetter, modelUpdater, registrar);
}
else if (isElement(component)) {
registrar = mergeNativeKeyUpEventListener(component, uiGetter, modelUpdater, registrar);
}
else {
throw new RuntimeException("Cannot bind component " + component.toString() + " on key up events, " + component.toString()
+ " is not a ValueBoxBase or an element wrapper");
}
}
return registrar;
}
private static boolean isElement(final Object obj) {
return obj instanceof JavaScriptObject && Node.is((JavaScriptObject) obj) && Element.is((Node) obj);
}
private static native JavaScriptObject wrap(Runnable runnable) /*-{
return function() {
runnable.@java.lang.Runnable::run()();
};
}-*/;
private static native void addChangeEventListener(Object element, JavaScriptObject listener) /*-{
element.addEventListener("change", listener);
}-*/;
private static native void addKeyUpEventListener(Object element, JavaScriptObject listener) /*-{
element.addEventListener("keyup", listener);
}-*/;
private static native void removeChangeEventListener(Object element, JavaScriptObject listener) /*-{
element.removeEventListener("change", listener);
}-*/;
private static native void removeKeyUpEventListener(Object element, JavaScriptObject listener) /*-{
element.removeEventListener("keyup", listener);
}-*/;
private static Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> mergeValueBoxKeyUpHandler(
final Object component, final Consumer<Object> modelUpdater,
Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> registrar) {
registrar = mergeToLeft(registrar, () -> {
logger.debug("Adding ValueBox keyup handler to {}", component);
final HandlerRegistration keyUpHandlerReg = ((ValueBoxBase) component)
.addKeyUpHandler(event -> modelUpdater.accept(((ValueBoxBase) component).getText()));
return Collections.singletonMap(KeyUpEvent.class, keyUpHandlerReg);
});
return registrar;
}
private static Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> mergeHasValueChangeHandler(
final Object component, final Consumer<Object> modelUpdater,
Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> registrar) {
registrar = mergeToLeft(registrar, () -> {
logger.debug("Adding value change handler to {}", component);
final HandlerRegistration valueHandlerReg = ((HasValue) component).addValueChangeHandler(event -> {
final Object value = ((HasValue) component).getValue();
modelUpdater.accept(value);
});
return Collections.singletonMap(ValueChangeEvent.class, valueHandlerReg);
});
return registrar;
}
private static Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> mergeNativeChangeEventListener(
final Object component, final Optional<Supplier<Object>> uiGetter, final Consumer<Object> modelUpdater,
Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> registrar) {
registrar = mergeToLeft(registrar, () -> {
logger.debug("Adding native change event listener to {}", component);
final JavaScriptObject listener = wrap(() -> uiGetter.ifPresent(getter -> modelUpdater.accept(getter.get())));
addChangeEventListener(component, listener);
final HandlerRegistration hr = () -> removeChangeEventListener(component, listener);
return Collections.singletonMap(ValueChangeEvent.class, hr);
});
return registrar;
}
private static Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> mergeNativeKeyUpEventListener(
final Object component, final Optional<Supplier<Object>> uiGetter, final Consumer<Object> modelUpdater,
Supplier<Map<Class<? extends GwtEvent>, HandlerRegistration>> registrar) {
registrar = mergeToLeft(registrar, () -> {
final JavaScriptObject listener = wrap(() -> {
logger.debug("keyup listener invoked for {}", component);
uiGetter.ifPresent(getter -> {
final Object value = getter.get();
logger.debug("keyup listener invoked with UI value {}", value);
modelUpdater.accept(value);
});
});
logger.debug("Adding native keyup listener to {}...", component);
addKeyUpEventListener(component, listener);
logger.debug("Added native keyup listener to {}", component);
final HandlerRegistration hr = () -> removeKeyUpEventListener(component, listener);
return Collections.singletonMap(ValueChangeEvent.class, hr);
});
return registrar;
}
private static void checkWidgetHasTextOrValue(final Object component) {
if (component instanceof Widget && !(component instanceof HasText || component instanceof TakesValue)) {
throw new RuntimeException(
"Widget must implement either " + TakesValue.class.getName() + " or " + HasText.class.getName() + "!");
}
}
private static <K, V> Supplier<Map<K, V>> mergeToLeft(final Supplier<Map<K, V>> f, final Supplier<Map<K, V>> g) {
return () -> {
final Map<K, V> retVal = f.get();
retVal.putAll(g.get());
return retVal;
};
}
/**
* Creates a data binder for a nested property to support property chains. The
* nested data binder is initialized with the current value of the specified
* property, or with a new instance of the property type if the value is null.
* The proxy's value for this property is then replaced with the proxy managed
* by the nested data binder.
*
* @param property
* the property of the model to bind the widget to, must not be null.
* The property must be of a @Bindable type.
*/
private DataBinder createNestedBinder(final String property, final StateSync initialState) {
final String bindableProperty = property.substring(0, property.indexOf("."));
DataBinder<Object> binder = binders.get(bindableProperty);
if (!propertyTypes.containsKey(bindableProperty)) {
final String type = proxy.getClass().getSuperclass().getSimpleName();
throw new NonExistingPropertyException(type, bindableProperty);
}
if (!propertyTypes.get(bindableProperty).isBindable()) {
throw new RuntimeException("The type of property " + bindableProperty + " ("
+ propertyTypes.get(bindableProperty).getType().getName() + ") is not a @Bindable type!");
}
if (binder == null) {
if (proxy.get(bindableProperty) == null) {
binder = DataBinder.forType(propertyTypes.get(bindableProperty).getType());
}
else {
binder = DataBinder.forModel(proxy.get(bindableProperty));
}
binders.put(bindableProperty, binder);
for (final PropertyChangeHandler<?> handler : propertyChangeHandlerSupport.specificPropertyHandlers.get("**")) {
binder.addPropertyChangeHandler("**", handler);
}
}
else if (proxy.get(bindableProperty) != null) {
binder.setModel(proxy.get(bindableProperty), initialState, true);
}
proxy.set(bindableProperty, binder.getModel());
knownValues.put(bindableProperty, binder.getModel());
if (property.indexOf('.') != property.lastIndexOf('.')) {
((BindableProxy<?>) binder.getModel()).getBindableProxyAgent().createNestedBinder(property.substring(property.indexOf('.')+1), initialState);
}
return binder;
}
private void validatePropertyExpr(final String property) {
if (property.startsWith(".") || property.endsWith(".")) {
throw new InvalidPropertyExpressionException(
"Binding expression (property chain) cannot start or end with '.' : " + property);
}
if (property.contains("*.")) {
throw new InvalidPropertyExpressionException("Wildcards can only appear at the end of property expressions : "
+ property);
}
}
/**
* Unbinds the property with the given name.
*
* @param property
* the name of the model property to unbind, must not be null.
*/
public void unbind(final Binding binding) {
final String property = binding.getProperty();
validatePropertyExpr(property);
final int dotPos = property.indexOf(".");
if (dotPos > 0) {
final String bindableProperty = property.substring(0, dotPos);
final DataBinder binder = binders.get(bindableProperty);
if (binder != null) {
final BindableProxyAgent<T> nestedAgent = ((BindableProxy<T>) binder.getModel()).getBindableProxyAgent();
final Collection<Binding> nestedBindings = nestedAgent.bindings.get(property.substring(dotPos + 1));
for (final Binding nestedBinding : nestedBindings.toArray(new Binding[nestedBindings.size()])) {
if (binding.getComponent() == nestedBinding.getComponent()) {
nestedAgent.unbind(nestedBinding);
}
}
}
}
binding.removeHandlers();
bindings.remove(property, binding);
if (bindings.isEmpty()) {
BindableProxyFactory.removeCachedProxyForModel(target);
}
}
/**
* Updates all bound widgets if necessary (if a bound property's value has
* changed). This method is invoked in case a bound property changed outside
* the property's write method (when using a non accessor method).
*/
void updateWidgetsAndFireEvents() {
for (final String property : propertyTypes.keySet()) {
final Object knownValue = knownValues.get(property);
final Object actualValue = proxy.get(property);
if ((knownValue == null && actualValue != null) || (knownValue != null && !knownValue.equals(actualValue))) {
final DataBinder nestedBinder = binders.get(property);
if (nestedBinder != null) {
nestedBinder.setModel(actualValue, StateSync.FROM_MODEL, true);
proxy.set(property, nestedBinder.getModel());
}
updateWidgetsAndFireEvent(true, property, knownValue, actualValue);
}
}
}
/**
* Updates all bound widgets and fires the corresponding {@link PropertyChangeEvent}.
*
* @param
* <P>
* The property type of the changed property.
* @param sync
* True if a {@link BindableListChangeHandler} component bound to a list should have it's value set via
* {@link TakesValue#setValue(Object)}.
* @param property
* The name of the property that changed. Must not be null.
* @param oldValue
* The old value of the property.
* @param newValue
* The new value of the property.
*/
<P> void updateWidgetsAndFireEvent(final boolean sync, final String property, final P oldValue, final P newValue) {
updateWidgetsAndFireEvent(sync, property, oldValue, newValue, null);
}
/**
* Updates all bound widgets and fires the corresponding
* {@link PropertyChangeEvent}.
*
* @param <P>
* The property type of the changed property.
* @param sync
* True if a {@link BindableListChangeHandler} component bound to a list should have it's value set via
* {@link TakesValue#setValue(Object)}.
* @param property
* The name of the property that changed.
* @param oldValue
* The old value of the property.
* @param newValue
* The new value of the property.
* @param excluding
* A widget reference that does not need to be updated (the origin of
* the value change event).
*/
private <P> void updateWidgetsAndFireEvent(final boolean sync, final String property, final P oldValue, final P newValue,
final Object excluding) {
for (final Binding binding : bindings.get(property)) {
final Object component = binding.getComponent();
final Converter converter = binding.getConverter();
if (component == excluding)
continue;
if (!sync && binding.propertyIsList() && component instanceof BindableListChangeHandler)
continue;
if (component instanceof TakesValue) {
updateComponentValue(newValue, (TakesValue) component, converter);
}
else if (component instanceof HasText) {
updateComponentValue(newValue, (HasText) component, converter);
}
else if (component instanceof IsElement || isElement(component)) {
final Element element = BoundUtil.asElement(component instanceof IsElement ? ((IsElement) component).getElement() : component);
final ElementWrapperWidget<?> wrapper = ElementWrapperWidget.getWidget(element);
if (wrapper instanceof TakesValue) {
updateComponentValue(newValue, (TakesValue) wrapper, converter);
}
else if (wrapper instanceof HasText) {
updateComponentValue(newValue, (HasText) wrapper, converter);
}
}
}
maybeFirePropertyChangeEvent(property, oldValue, newValue);
}
private <P> void updateComponentValue(final P newValue, final HasText component, final Converter converter) {
assert String.class.equals(converter.getComponentType());
final Object widgetValue = converter.toWidgetValue(newValue);
component.setText((String) widgetValue);
}
private <P> void updateComponentValue(final P newValue, final TakesValue component, final Converter converter) {
final Object widgetValue = converter.toWidgetValue(newValue);
component.setValue(widgetValue);
}
/**
* Fires a property change event unless the property is {@code "this"}. The {@code "this"} property is only fired for
* types with no other properties.
*
* @param
* <P>
* The property type of the changed property.
* @param property
* The name of the property that changed. Must not be null.
* @param oldValue
* The old value of the property.
* @param newValue
* The new value of the property.
* @return true Iff property change handlers were notified for this type.
*/
private <P> boolean maybeFirePropertyChangeEvent(final String property, final P oldValue, final P newValue) {
knownValues.put(property, newValue);
final PropertyChangeEvent<P> event = new PropertyChangeEvent<>(proxy, Assert.notNull(property), oldValue, newValue);
if (!"this".equals(property) || propertyTypes.size() == 1) {
propertyChangeHandlerSupport.notifyHandlers(event);
return true;
}
else {
return false;
}
}
/**
* Synchronizes the state of the provided widgets and model property based on the value of the provided
* {@link StateSync}.
*
* @param component
* The widget to synchronize. Must not be null.
* @param property
* The name of the model property that should be synchronized. Must not be null.
* @param converter
* The converter specified for the property binding. Must not be null.
* @param uiGetter
* An optional function for getting the value from the UI component. Must not be null.
* @param initialState
* If {@link StateSync#FROM_MODEL} the UI value will be updated from the model. If {@link StateSync#FROM_UI}
* the model value will be updated from the UI. If null no synchronization is performed.
*/
private void syncState(final Object component, final String property, final Converter converter,
final Optional<Supplier<Object>> uiGetter, final StateSync initialState) {
Assert.notNull(component);
Assert.notNull(property);
if (initialState != null) {
final Object modelValue = proxy.get(property);
final Optional<Object> uiValue = uiGetter.map(f -> f.get());
final Object value = uiValue.map(v -> initialState.getInitialValue(modelValue, v)).orElse(modelValue);
if (initialState == StateSync.FROM_MODEL) {
updateWidgetsAndFireEvent(true, property, knownValues.get(property), value);
}
else if (initialState == StateSync.FROM_UI) {
final Object newValue = converter.toModelValue(value);
proxy.set(property, newValue);
maybeFirePropertyChangeEvent(property, knownValues.get(property), newValue);
updateWidgetsAndFireEvent(true, property, knownValues.get(property), newValue, component);
}
}
}
/**
* Ensures that the given list property is wrapped in a
* {@link BindableListWrapper}, so changes to the list become observable.
*
* @param property
* the name of the list property
*
* @return a new the wrapped (proxied) list or the provided list if already
* proxied
*/
private List ensureBoundListIsProxied(final String property) {
final List oldList = (List) proxy.get(property);
final List newList = ensureBoundListIsProxied(property, oldList);
if (oldList != newList)
updateWidgetsAndFireEvent(true, property, proxy.get(property), newList);
return newList;
}
/**
* Ensures that the given list property is wrapped in a
* {@link BindableListWrapper}, so changes to the list become observable.
*
* @param property
* the name of the list property
* @param list
* the list that needs to be proxied
*
* @return a new the wrapped (proxied) list or the provided list if already
* proxied
*/
List ensureBoundListIsProxied(final String property, final List list) {
if (!(list instanceof BindableListWrapper) && bindings.containsKey(property) && list != null) {
final BindableListWrapper newList = new BindableListWrapper(list);
addHandlersForBindableListWrapper(property, newList);
return newList;
}
return list;
}
private void addHandlersForBindableListWrapper(final String property, final BindableListWrapper newList) {
modelChangeHandlers.add(newList.addChangeHandler(new UnspecificListChangeHandler() {
@Override
void onListChanged(final List oldList) {
updateWidgetsAndFireEvent(false, property, oldList, newList);
}
}));
for (final Binding binding : bindings.get(property)) {
if (binding.getComponent() instanceof BindableListChangeHandler) {
modelChangeHandlers.add(newList.addChangeHandler((BindableListChangeHandler) binding.getComponent()));
}
}
}
/**
* Returns the {@link PropertyChangeHandlerSupport} object of this agent
* containing all change handlers that have been registered for the
* corresponding model proxy.
*
* @return propertyChangeHandlerSupport object, never null.
*/
public PropertyChangeHandlerSupport getPropertyChangeHandlers() {
return propertyChangeHandlerSupport;
}
@Override
public PropertyChangeUnsubscribeHandle addPropertyChangeHandler(final PropertyChangeHandler handler) {
propertyChangeHandlerSupport.addPropertyChangeHandler(handler);
return new OneTimeUnsubscribeHandle() {
@Override
public void doUnsubscribe() {
propertyChangeHandlerSupport.removePropertyChangeHandler(handler);
}
};
}
@Override
public <P> PropertyChangeUnsubscribeHandle addPropertyChangeHandler(final String property, final PropertyChangeHandler<P> handler) {
validatePropertyExpr(property);
final Collection<PropertyChangeUnsubscribeHandle> unsubHandles = new ArrayList<>();
final int dotPos = property.indexOf(".");
if (dotPos > 0) {
final DataBinder nested = createNestedBinder(property, StateSync.FROM_MODEL);
unsubHandles.add(nested.addPropertyChangeHandler(property.substring(dotPos + 1), handler));
}
else if (property.equals("*")) {
propertyChangeHandlerSupport.addPropertyChangeHandler(handler);
unsubHandles.add(new PropertyChangeUnsubscribeHandle() {
@Override
public void unsubscribe() {
propertyChangeHandlerSupport.removePropertyChangeHandler(handler);
}
});
}
else if (property.equals("**")) {
for (final DataBinder nested : binders.values()) {
unsubHandles.add(nested.addPropertyChangeHandler(property, handler));
}
propertyChangeHandlerSupport.addPropertyChangeHandler(handler);
unsubHandles.add(new PropertyChangeUnsubscribeHandle() {
@Override
public void unsubscribe() {
propertyChangeHandlerSupport.removePropertyChangeHandler(handler);
}
});
}
propertyChangeHandlerSupport.addPropertyChangeHandler(property, handler);
unsubHandles.add(new PropertyChangeUnsubscribeHandle() {
@Override
public void unsubscribe() {
propertyChangeHandlerSupport.removePropertyChangeHandler(property, handler);
}
});
return new OneTimeUnsubscribeHandle() {
@Override
public void doUnsubscribe() {
for (final PropertyChangeUnsubscribeHandle handle : unsubHandles) {
handle.unsubscribe();
}
}
};
}
/**
* Merges the provided {@link PropertyChangeHandler}s of the provided agent
* instance. If a handler instance is already registered on this agent, it
* will NOT be added again.
*
* @param pchs
* the instance who's change handlers will be merged, must not be
* null.
*/
public void mergePropertyChangeHandlers(final PropertyChangeHandlerSupport pchs) {
Assert.notNull(pchs);
for (final PropertyChangeHandler pch : pchs.handlers) {
if (!propertyChangeHandlerSupport.handlers.contains(pch)) {
addPropertyChangeHandler(pch);
}
}
for (final String pchKey : pchs.specificPropertyHandlers.keys()) {
for (final PropertyChangeHandler pch : pchs.specificPropertyHandlers.get(pchKey)) {
if (!propertyChangeHandlerSupport.specificPropertyHandlers.containsEntry(pchKey, pch)) {
addPropertyChangeHandler(pchKey, pch);
}
}
}
}
/**
* Compares property values between this agent and the provided agent recursively and fires
* {@link PropertyChangeEvent}s for all differences.
*
* @param other
* the agent to compare against.
* @param initialState
* If {@link StateSync#FROM_MODEL} the state from this agent's model overrides the other. If
* {@link StateSync#FROM_UI} the state from the other agent's model overrides this one. If null, default to
* {@link StateSync#FROM_MODEL}.
*/
public void fireChangeEvents(final BindableProxyAgent other, final StateSync initialState) {
for (final String property : propertyTypes.keySet()) {
final Object curValue,
oldValue,
thisValue = knownValues.get(property),
otherValue = other.knownValues.get(property);
final StateSync state = (initialState != null ? initialState : StateSync.FROM_MODEL);
curValue = state.getInitialValue(thisValue, otherValue);
oldValue = state.getInitialValue(otherValue, thisValue);
if ((curValue == null && oldValue != null) || (curValue != null && !curValue.equals(oldValue))) {
final DataBinder nestedBinder = binders.get(property);
final DataBinder otherNestedBinder = (DataBinder) other.binders.get(property);
if (nestedBinder != null && otherNestedBinder != null) {
final BindableProxyAgent nestedAgent = ((BindableProxy<T>) nestedBinder.getModel()).getBindableProxyAgent();
final BindableProxyAgent otherNestedAgent = ((BindableProxy<T>) otherNestedBinder.getModel()).getBindableProxyAgent();
nestedAgent.fireChangeEvents(otherNestedAgent, state);
}
maybeFirePropertyChangeEvent(property, oldValue, curValue);
}
}
}
public void clearModelHandlers() {
for (final HandlerRegistration reg : modelChangeHandlers) {
reg.removeHandler();
}
modelChangeHandlers.clear();
for (final DataBinder<?> binder : binders.values()) {
getAgent(binder).clearModelHandlers();
}
}
private static BindableProxyAgent<?> getAgent(final DataBinder<?> binder) {
return ((BindableProxy<?>) binder.getModel()).getBindableProxyAgent();
}
}