groovy.util.ObservableMap Maven / Gradle / Ivy
/*
* Copyright 2003-2013 the original author or authors.
*
* 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 groovy.util;
import groovy.lang.Closure;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.util.*;
/**
* Map decorator that will trigger PropertyChangeEvents when a value changes.
* An optional Closure may be specified and will work as a filter, if it returns
* true the property will trigger an event (if the value indeed changed),
* otherwise it won't. The Closure may receive 1 or 2 parameters, the single one
* being the value, the other one both the key and value, for example:
*
* // skip all properties whose value is a closure
* def map = new ObservableMap( {!(it instanceof Closure)} )
*
* // skip all properties whose name matches a regex
* def map = new ObservableMap( { name, value -> !(name =~ /[A-Z+]/) } )
*
* The current implementation will trigger specialized events in the following scenarios,
* you need not register a different listener as those events extend from PropertyChangeEvent
*
* - ObservableMap.PropertyAddedEvent - a new property is added to the map
* - ObservableMap.PropertyRemovedEvent - a property is removed from the map
* - ObservableMap.PropertyUpdatedEvent - a property changes value (same as regular PropertyChangeEvent)
* - ObservableMap.PropertyClearedEvent - all properties have been removed from the map
* - ObservableMap.MultiPropertyEvent - triggered by calling map.putAll(), contains Added|Updated events
*
*
* Bound properties
*
* - content - read-only.
* - size - read-only.
*
*
* @author Andres Almiray
*/
public class ObservableMap implements Map {
private Map delegate;
private PropertyChangeSupport pcs;
private Closure test;
public static final String SIZE_PROPERTY = "size";
public static final String CONTENT_PROPERTY = "content";
public static final String CLEARED_PROPERTY = "cleared";
public ObservableMap() {
this(new LinkedHashMap(), null);
}
public ObservableMap(Closure test) {
this(new LinkedHashMap(), test);
}
public ObservableMap(Map delegate) {
this(delegate, null);
}
public ObservableMap(Map delegate, Closure test) {
this.delegate = delegate;
this.test = test;
pcs = new PropertyChangeSupport(this);
}
protected Map getMapDelegate() {
return delegate;
}
protected Closure getTest() {
return test;
}
public Map getContent() {
return Collections.unmodifiableMap(delegate);
}
protected void firePropertyClearedEvent(Map values) {
firePropertyEvent(new PropertyClearedEvent(this, values));
}
protected void firePropertyAddedEvent(Object key, Object value) {
firePropertyEvent(new PropertyAddedEvent(this, String.valueOf(key), value));
}
protected void firePropertyUpdatedEvent(Object key, Object oldValue, Object newValue) {
firePropertyEvent(new PropertyUpdatedEvent(this, String.valueOf(key), oldValue, newValue));
}
protected void fireMultiPropertyEvent(List events) {
firePropertyEvent(new MultiPropertyEvent(this, (PropertyEvent[]) events.toArray(new PropertyEvent[events.size()])));
}
protected void fireMultiPropertyEvent(PropertyEvent[] events) {
firePropertyEvent(new MultiPropertyEvent(this, events));
}
protected void firePropertyRemovedEvent(Object key, Object value) {
firePropertyEvent(new PropertyRemovedEvent(this, String.valueOf(key), value));
}
protected void firePropertyEvent(PropertyEvent event) {
pcs.firePropertyChange(event);
}
protected void fireSizeChangedEvent(int oldValue, int newValue) {
pcs.firePropertyChange(new PropertyChangeEvent(this, SIZE_PROPERTY, oldValue, newValue));
}
// Map interface
public void clear() {
int oldSize = size();
Map values = new HashMap();
if (!delegate.isEmpty()) {
values.putAll(delegate);
}
delegate.clear();
firePropertyClearedEvent(values);
fireSizeChangedEvent(oldSize, size());
}
public boolean containsKey(Object key) {
return delegate.containsKey(key);
}
public boolean containsValue(Object value) {
return delegate.containsValue(value);
}
public Set entrySet() {
return delegate.entrySet();
}
public boolean equals(Object o) {
return delegate.equals(o);
}
public Object get(Object key) {
return delegate.get(key);
}
public int hashCode() {
return delegate.hashCode();
}
public boolean isEmpty() {
return delegate.isEmpty();
}
public Set keySet() {
return delegate.keySet();
}
public Object put(Object key, Object value) {
int oldSize = size();
Object oldValue = null;
boolean newKey = !delegate.containsKey(key);
if (test != null) {
oldValue = delegate.put(key, value);
Object result = null;
if (test.getMaximumNumberOfParameters() == 2) {
result = test.call(new Object[]{key, value});
} else {
result = test.call(value);
}
if (result != null && result instanceof Boolean && (Boolean) result) {
if (newKey) {
firePropertyAddedEvent(key, value);
fireSizeChangedEvent(oldSize, size());
} else if (oldValue != value) {
firePropertyUpdatedEvent(key, oldValue, value);
}
}
} else {
oldValue = delegate.put(key, value);
if (newKey) {
firePropertyAddedEvent(key, value);
fireSizeChangedEvent(oldSize, size());
} else if (oldValue != value) {
firePropertyUpdatedEvent(key, oldValue, value);
}
}
return oldValue;
}
public void putAll(Map map) {
int oldSize = size();
if (map != null) {
List events = new ArrayList();
for (Object o : map.entrySet()) {
Entry entry = (Entry) o;
String key = String.valueOf(entry.getKey());
Object newValue = entry.getValue();
Object oldValue = null;
boolean newKey = !delegate.containsKey(key);
if (test != null) {
oldValue = delegate.put(key, newValue);
Object result = null;
if (test.getMaximumNumberOfParameters() == 2) {
result = test.call(new Object[]{key, newValue});
} else {
result = test.call(newValue);
}
if (result != null && result instanceof Boolean && (Boolean) result) {
if (newKey) {
events.add(new PropertyAddedEvent(this, key, newValue));
} else if (oldValue != newValue) {
events.add(new PropertyUpdatedEvent(this, key, oldValue, newValue));
}
}
} else {
oldValue = delegate.put(key, newValue);
if (newKey) {
events.add(new PropertyAddedEvent(this, key, newValue));
} else if (oldValue != newValue) {
events.add(new PropertyUpdatedEvent(this, key, oldValue, newValue));
}
}
}
if (events.size() > 0) {
fireMultiPropertyEvent(events);
fireSizeChangedEvent(oldSize, size());
}
}
}
public Object remove(Object key) {
int oldSize = size();
Object result = delegate.remove(key);
if (key != null) {
firePropertyRemovedEvent(key, result);
fireSizeChangedEvent(oldSize, size());
}
return result;
}
public int size() {
return delegate.size();
}
public int getSize() {
return size();
}
public Collection values() {
return delegate.values();
}
// observable interface
public void addPropertyChangeListener(PropertyChangeListener listener) {
pcs.addPropertyChangeListener(listener);
}
public void addPropertyChangeListener(String propertyName, PropertyChangeListener listener) {
pcs.addPropertyChangeListener(propertyName, listener);
}
public PropertyChangeListener[] getPropertyChangeListeners() {
return pcs.getPropertyChangeListeners();
}
public PropertyChangeListener[] getPropertyChangeListeners(String propertyName) {
return pcs.getPropertyChangeListeners(propertyName);
}
public void removePropertyChangeListener(PropertyChangeListener listener) {
pcs.removePropertyChangeListener(listener);
}
public void removePropertyChangeListener(String propertyName, PropertyChangeListener listener) {
pcs.removePropertyChangeListener(propertyName, listener);
}
public boolean hasListeners(String propertyName) {
return pcs.hasListeners(propertyName);
}
public enum ChangeType {
ADDED, UPDATED, REMOVED, CLEARED, MULTI, NONE;
public static final Object oldValue = new Object();
public static final Object newValue = new Object();
public static ChangeType resolve(int ordinal) {
switch (ordinal) {
case 0:
return ADDED;
case 2:
return REMOVED;
case 3:
return CLEARED;
case 4:
return MULTI;
case 5:
return NONE;
case 1:
default:
return UPDATED;
}
}
}
public abstract static class PropertyEvent extends PropertyChangeEvent {
private ChangeType type;
public PropertyEvent(Object source, String propertyName, Object oldValue, Object newValue, ChangeType type) {
super(source, propertyName, oldValue, newValue);
this.type = type;
}
public int getType() {
return type.ordinal();
}
public ChangeType getChangeType() {
return type;
}
public String getTypeAsString() {
return type.name().toUpperCase();
}
}
public static class PropertyAddedEvent extends PropertyEvent {
public PropertyAddedEvent(Object source, String propertyName, Object newValue) {
super(source, propertyName, null, newValue, ChangeType.ADDED);
}
}
public static class PropertyUpdatedEvent extends PropertyEvent {
public PropertyUpdatedEvent(Object source, String propertyName, Object oldValue, Object newValue) {
super(source, propertyName, oldValue, newValue, ChangeType.UPDATED);
}
}
public static class PropertyRemovedEvent extends PropertyEvent {
public PropertyRemovedEvent(Object source, String propertyName, Object oldValue) {
super(source, propertyName, oldValue, null, ChangeType.REMOVED);
}
}
public static class PropertyClearedEvent extends PropertyEvent {
private Map values = new HashMap();
public PropertyClearedEvent(Object source, Map values) {
super(source, ObservableMap.CLEARED_PROPERTY, values, null, ChangeType.CLEARED);
if (values != null) {
this.values.putAll(values);
}
}
public Map getValues() {
return Collections.unmodifiableMap(values);
}
}
public static class MultiPropertyEvent extends PropertyEvent {
public static final String MULTI_PROPERTY = "groovy_util_ObservableMap_MultiPropertyEvent_MULTI";
private PropertyEvent[] events = new PropertyEvent[0];
public MultiPropertyEvent(Object source, PropertyEvent[] events) {
super(source, MULTI_PROPERTY, ChangeType.oldValue, ChangeType.newValue, ChangeType.MULTI);
if (events != null && events.length > 0) {
this.events = new PropertyEvent[events.length];
System.arraycopy(events, 0, this.events, 0, events.length);
}
}
public PropertyEvent[] getEvents() {
PropertyEvent[] copy = new PropertyEvent[events.length];
System.arraycopy(events, 0, copy, 0, events.length);
return copy;
}
}
}